Resin composition, resin material, molded article, insulating material for communication cable, insulating material for automotive cable, communication cable, and automotive cable

Abstract

The resin composition contains a cyclic olefin resin (A) and a linear low-density polyethylene (B). The glass transition temperature (Tg) of the cyclic olefin resin (A) is within the range of 150-200°C; the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst; and the proportion of the cyclic olefin resin (A) relative to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is from more than 30 mass% to less than 50 mass%.

Description

Resin composition, resin material, molded product, insulating material for communication cables, insulating material for in-vehicle cables, communication cables, and in-vehicle cables

[0001] The present invention relates to a resin composition, a resin material, a molded product, an insulating material for communication cables, an insulating material for in-vehicle cables, a communication cable, and an in-vehicle cable.

[0002] A coaxial cable is a type of covered wire, mainly formed by a central conductor, an insulating layer provided on its outer periphery, an outer conductor provided on its outer periphery, and a sheath forming the outermost layer. Coaxial cables have been widely used in various electrical communication applications such as wireless communication devices, network devices, broadcasting devices, and electronic measuring instruments.

[0003] As an example of technology related to coaxial cables, Patent Document 1 describes a coaxial cable having a layer formed by foam molding a resin composition containing a cyclic olefin resin and low-density polyethylene and / or linear low-density polyethylene as an insulating layer, and the degree of foaming of the insulating layer is 80% to 90%.

[0004] International Publication No. 2009 / 041116

[0005] As described above, coaxial cables have mainly been used for electrical communication applications, but recently, the range of applications of coaxial cables has also expanded, such as a large number of electrical communication devices being installed in transportation equipment such as automobiles. When using a coaxial cable for automotive applications, the operating environment becomes more severe compared to previous electrical communication applications, so performance that can cope with this is required. As an example of specific required performance, heat resistance that can withstand use in a high-temperature environment can be mentioned. In the insulating layer, it is required that deformation and shrinkage under high-temperature conditions are small, and high elongation can be maintained and disconnection does not occur even after being left for a long time under high-temperature conditions.

[0006] One of the problems of the present disclosure is to provide a resin composition, a resin material, a molded product, an insulating material for communication cables, an insulating material for in-vehicle cables, a communication cable, and an in-vehicle cable that have small deformation and shrinkage under high-temperature conditions and can maintain high elongation even after being left for a long time under high-temperature conditions.

[0007] This disclosure includes, but is not limited to, the following embodiments. One embodiment relates to a resin composition comprising a cyclic olefin resin (A) and linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass.

[0008] Another embodiment relates to a resin composition comprising a cyclic olefin resin (C) and linear low-density polyethylene (D), wherein when formed into a film under the following conditions, the linear low-density polyethylene (D) forms a sea phase and the cyclic olefin resin (C) forms an island phase in the central 200 μm range of the film thickness. Extruder: 20 mm diameter single-screw extruder Die: 150 mm wide coat hanger die, lip opening 0.35 mm Screw: L / D = 29 full-flight screw, compression ratio 2.9 Film formation temperature: Cylinder and die temperature 290°C Discharge rate: 2.3 kg / h Cooling roll temperature: 50°C Film thickness: 300 μm

[0009] Another embodiment relates to a resin material comprising pellets (α) containing a cyclic olefin resin (A) and pellets (β) containing linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the pellets (α) and (β) are included such that the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass.

[0010] According to this disclosure, it is possible to provide resin compositions, resin materials, molded articles, insulating materials for communication cables, insulating materials for automotive cables, communication cables, and automotive cables that exhibit little deformation and shrinkage under high-temperature conditions and maintain high elongation even after being left for a long time under high-temperature conditions.

[0011] Figure 1 is a cross-sectional image of the scanning electron microscope observation processed film obtained in Example 1. Figure 2 is a cross-sectional image of the scanning electron microscope observation processed film obtained in Example 2. Figure 3 is a cross-sectional image of the scanning electron microscope observation processed film obtained in Comparative Example 1.

[0012] Embodiments of the present disclosure will be described in detail below. The present disclosure is not limited to the following embodiments. One embodiment of the resin composition comprises a cyclic olefin resin (A) and linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass. This may be referred to as resin composition (1) below.

[0013] The cyclic olefin resin (A) is one in which the monomers constituting the cyclic olefin resin (A) contain a cyclic olefin compound, and the presence or absence of other copolymer components is irrelevant. It may also be a hydrogenated (co)polymer of monomers containing a cyclic olefin compound. One type of cyclic olefin resin (A) may be used alone, or two or more types may be used in combination.

[0014] The glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C. Having the glass transition temperature (Tg) of the cyclic olefin resin (A) within this range results in a resin composition that exhibits minimal deformation and shrinkage under high-temperature conditions and maintains high elongation even after being left for extended periods under high-temperature conditions.

[0015] In this disclosure, the glass transition temperature (Tg) of the cyclic olefin resin (A) is a value measured by differential scanning calorimetry (DSC) under the following conditions, in accordance with ISO 11357-1, -2, -3. Sample amount: 7.5 to 11.0 mg Temperature profile: Heating from 40°C to 250°C at 20°C / min, isothermal holding at 250°C for 2 minutes, cooling from 250°C to 40°C at 20°C / min, isothermal holding at 40°C for 5 minutes, heating from 40°C to 250°C at 20°C / min, cooling from 250°C to 40°C at 80°C / min Analysis conditions: Data from the second heating process is used. The glass transition temperature (Tg) is measured using the Midpoint.

[0016] The melt viscosity of the cyclic olefin resin (A) is not particularly limited, but for example, at a barrel temperature of 290°C and a shear rate of 122 sec. －１ The measured value may be 300 Pa·s or more, 350 Pa·s or more, or 400 Pa·s or more. It may also be 600 Pa·s or less, 550 Pa·s or less, or 500 Pa·s or less. The melt viscosity of the cyclic olefin resin (A) may be in the range of 300 to 600 Pa·s.

[0017] Specific examples of cyclic olefin resins (A) include the following: Cyclic olefin resin (A1): Addition polymer of a cyclic olefin compound or its hydrogenated form Cyclic olefin resin (A2): Copolymer of monomers containing a cyclic olefin compound and an α-olefin compound or its hydrogenated form Cyclic olefin resin (A3): Ring-opening (co)polymer of a cyclic olefin compound or its hydrogenated form Cyclic olefin resin (A4): Cyclic olefin resins (A1) to (A3) with a polar group-containing unsaturated compound grafted, copolymerized, or grafted and copolymerized.

[0018] The cyclic olefin compound may be any compound having a non-aromatic carbon-carbon double bond in the cyclic structure. The specific structure of the cyclic olefin compound is not particularly limited, and various types can be used. The cyclic olefin compound may be used alone or in combination of two or more. An example of a preferred cyclic olefin compound is, for example, a compound represented by the following general formula (1).

[0019]

[0020] [In the general formula (1), R １ ~R １２ are each independently either a hydrogen atom, a halogen atom, or a hydrocarbon group. R ９ and R １０ , R １１ and R １２ may combine to form a divalent hydrocarbon group. Also, R ９ or R １０ and R １１ or R １２ may bond to each other to form a ring. n represents 0 or a positive integer. When n is 2 or more, R ５ ~R ８ present in the molecular structure may all be different or some or all may be the same. ]

[0021] In the general formula (1), R １ ~R １２ are each independently either a hydrogen atom, a halogen atom, or a hydrocarbon group.

[0022] Among these, R １ ~R ８ may each independently be either hydrogen, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. Specific examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, etc. Specific examples of the alkyl group having 1 to 4 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, etc. When n in the general formula 1 is a positive integer of 2 or more, R ５ ~R ８They may all be different, or some or all of them may be the same.

[0023] Also, R ９ ~R １２ Each of these may independently be a hydrogen atom, a halogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. Specific examples of halogen atoms include those mentioned above. Specific examples of alkyl groups include, for example, the alkyl groups with 1 to 4 carbon atoms mentioned above, as well as alkyl groups with 5 to 20 carbon atoms such as pentyl, hexyl, octyl, decyl, lauryl, myristyl, palmityl, stearyl, and arachidyl groups. Specific examples of cycloalkyl groups include, for example, the cyclohexyl group. Specific examples of aryl groups include, for example, aryl groups without substituents on the aromatic ring, such as phenyl, naphthyl, and anthryl groups, as well as aryl groups with substituents on the aromatic ring, such as tolyl, xylyl, ethylphenyl, and isopropylphenyl groups. Specific examples of aralkyl groups include, for example, benzyl and phenethyl groups, as well as structural sites in which an aryl group is substituted on an alkyl group with 1 to 4 carbon atoms.

[0024] R in general formula (1) ９ and R １０ , R １１ and R １２ These may integrate to form a divalent hydrocarbon group. Specific examples of divalent hydrocarbon groups in this case include alkylidene groups such as ethylidene, propylidene, and isopropylidene.

[0025] R in general formula (1) ９ or R １０ And, R １１ or R １２ These elements may be bonded to each other to form a ring. The formed ring may be monocyclic or polycyclic. It may also be a ring having a bridging site, or a ring having a double bond. Furthermore, it may be a ring consisting of a combination of these rings. Substituents may be present on the carbon atoms forming the ring structure, and examples of substituents include alkyl groups having 1 to 4 carbon atoms.

[0026] Specific examples of cyclic olefin compounds represented by general formula (1) include, for example, bicyclo[2.2.1]hepta-2-ene (common name: norbornene), 5-methyl-bicyclo[2.2.1]hepta-2-ene, 5,5-dimethyl-bicyclo[2.2.1]hepta-2-ene, 5-ethyl-bicyclo[2.2.1]hepta-2-ene, 5-butyl-bicyclo[2.2.1]hepta-2-ene, and 5-ethylidene-bicyclo[2.2. 1) Bicyclic olefin compounds such as hepta-2-ene, 5-hexyl-bicyclo[2.2.1]hepta-2-ene, 5-octyl-bicyclo[2.2.1]hepta-2-ene, 5-octadecyl-bicyclo[2.2.1]hepta-2-ene, 5-methylidene-bicyclo[2.2.1]hepta-2-ene, 5-vinyl-bicyclo[2.2.1]hepta-2-ene, and 5-propenyl-bicyclo[2.2.1]hepta-2-ene;

[0027] Tricyclo[4.3.0.1 ２，５ Deca-3,7-diene (common name: dicyclopentadiene), tricyclo[4.3.0.1 ２，５ Deca-3-ene; tricyclo[4.4.0.1 ２，５ ]Undeca-3,7-diene or tricyclo[4.4.0.12,5]Undeca-3,8-diene or partially hydrogenated versions thereof (or adducts of cyclopentadiene and cyclohexene) are tricyclo[4.4.0.1 ２，５ ]undeca-3-ene; tricyclic olefin compounds such as 5-cyclopentyl-bicyclo[2.2.1]hepta-2-ene, 5-cyclohexyl-bicyclo[2.2.1]hepta-2-ene, 5-cyclohexenylbicyclo[2.2.1]hepta-2-ene, and 5-phenyl-bicyclo[2.2.1]hepta-2-ene;

[0028] Tetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene (also simply called tetracyclododecene), 8-methyltetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene, 8-ethyltetracyclo[4.4.0.1 ２，５ 1. ７，１０] Dodeca-3-ene, 8-methylidenetetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene, 8-ethylidenetetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene, 8-vinyltetracyclo[4,4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene, 8-propenyl-tetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Tetracyclic olefin compounds such as dodeca-3-ene;

[0029] 8-Cyclopentyl-Tetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene, 8-cyclohexyl-tetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene, 8-cyclohexenyl-tetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene, 8-phenyl-cyclopentyl-tetracyclo[4.4.0.1 ２，５ 1. ７，１０ ] Dodeca-3-ene; Tetracyclo[7.4.1 ３，６ . 0 １，９ . 0 ２，７ ] Tetradeca-4,9,11,13-tetraene (also known as 1,4-methano-1,4,4a,9a-tetrahydrofluorene), tetracyclo[8.4.1 ４，７ . 0 １，１０ . 0 ３，８ ] Pentadeca-5,10,12,14-tetraene (also known as 1,4-methano-1,4,4a,5,10,10a-hexahydroanthracene); pentacyclo[6.6.1.1 ３，６ . 0 ２，７ . 0 ９，１４ ]-4-Hexadecene, Pentacyclo[6.5.1.1 ３，６ . 0 ２，７ . 0 ９，１３ ]-4-Pentadecene, Pentacyclo[7.4.0.0 ２，７ 1. ３，６ 1. １０，１３ ]-4-pentadecene; heptacyclo[8.7.0.1２，９ 1. ４，７ 1. １１，１７ . 0 ３，８ . 0 １２，１６ ]-5-Eicosene, heptacyclo[8.7.0.1 ２，９ . 0 ３，８ 1. ４，７ . 0 １２，１７ 1. １３，ｌ６ Examples include polycyclic cyclic olefin compounds such as tetramers of 14-eicosene and cyclopentadiene.

[0030] Among these, bicyclo[2.2.1]hepta-2-ene (common name: norbornene) and tetracyclododecene are preferred.

[0031] In the cyclic olefin resin (A2), the α-olefin compound copolymerized with the cyclic olefin compound is not particularly limited in terms of its specific structure, such as the number of carbon atoms, and a wide variety of compounds can be used. One type of α-olefin compound may be used alone, or two or more types may be used in combination. Specific examples of α-olefin compounds include, for example, ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eicosene, and other α-olefin compounds having 2 to 20 carbon atoms. Among these, ethylene is preferred.

[0032] In the cyclic olefin resin (A4), the specific structure of the unsaturated compound having a polar group that is grafted, copolymerized, or grafted and copolymerized onto the cyclic olefin resins (A1) to (A3) is not particularly limited, as long as it has a polar group and a polymerizable unsaturated bond in one molecule, and a wide variety of compounds can be used. One type of unsaturated compound having a polar group may be used alone, or two or more types may be used in combination.

[0033] Examples of polar groups in unsaturated compounds having polar groups include carboxyl groups, acid anhydride groups, epoxy groups, amide groups, ester groups, and hydroxyl groups. Furthermore, polymerizable unsaturated bonds in unsaturated compounds having polar groups may be introduced as, for example, acryloyl groups, acryloyloxy groups, methacryloyl groups, methacryloyloxy groups, allyl groups, allyloxy groups, vinyl groups, and vinyloxy groups. Specific examples of unsaturated compounds having polar groups include (meth)acrylic acid, maleic acid, maleic anhydride, itaconic anhydride, glycidyl (meth)acrylate, alkyl (meth)acrylate (1-10 carbon atoms) esters, alkyl maleate (1-10 carbon atoms) esters, (meth)acrylamide, and 2-hydroxyethyl (meth)acrylate.

[0034] Among the cyclic olefin resins (A1) to (A4), when the resin composition is used as an insulating material for cables, cyclic olefin resins (A1) to (A3) are preferred from the viewpoint of dielectric constant. Furthermore, cyclic olefin resin (A2) is preferred because it results in a resin composition that exhibits little deformation and shrinkage under high-temperature conditions and can maintain high elongation even after being left for a long time under high-temperature conditions. Moreover, copolymers of monomers containing a cyclic olefin compound and an α-olefin compound are even more preferred.

[0035] In the cyclic olefin resin (A2), the monomers forming the copolymer may include compounds other than the cyclic olefin compound and the α-olefin compound. The specific structure of the other compounds is not particularly limited, as long as they have carbon-carbon double bonds that can copolymerize with the cyclic olefin compound and the α-olefin compound; a wide variety of compounds can be used. One type of other compound may be used alone, or two or more types may be used in combination.

[0036] Other specific examples of compounds include, for example, chain-like non-conjugated dienes such as 1,4-hexadiene, 1,6-octadiene, 2-methyl-1,5-hexadiene, 4-methyl-1,5-hexadiene, 5-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, and 7-methyl-1,6-octadiene; cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinyl-2-norbornene, 5-ethylidene-2-norbornene, and 5-methylene-2-norbornene. Examples include cyclic non-conjugated dienes such as runene, 5-isopropylidene-2-norbornene, 6-chloromethyl-5-isopropenyl-2-norbornene, and 4,9,5,8-dimethano-3a,4,4a,5,8,8a,9,9a-octahydro-1H-benzoindene; 2,3-diisopropylidene-5-norbornene; 2-ethylidene-3-isopropylidene-5-norbornene; and 2-propenyl-2,2-norbornadiene, which have two or more carbon-carbon double bonds in a single molecule. Among these, 1,4-hexadiene, 1,6-octadiene, and cyclic non-conjugated dienes are preferred, and dicyclopentadiene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, 5-methylene-2-norbornene, 1,4-hexadiene, and 1,6-octadiene are more preferred.

[0037] The ratio of the cyclic olefin compound to the total mass of monomers constituting the cyclic olefin resin (A2) is preferably 65% ​​by mass or more, and more preferably 70% by mass or more, in order to obtain a resin composition that exhibits less deformation and shrinkage under high-temperature conditions. Furthermore, in order to obtain a resin composition that can maintain high elongation even after being left for a long time under high-temperature conditions, it is preferably 95% by mass or less, and more preferably 90% by mass or less.

[0038] The ratio of the α-olefin compound to the total mass of monomers constituting the cyclic olefin resin (A2) is preferably 5% by mass or more, and more preferably 10% by mass or more, in order to obtain a resin composition that can maintain high elongation even after being left for a long time under high temperature conditions. Furthermore, it is preferably 35% by mass or less, and more preferably 30% by mass or less, in order to obtain a resin composition that exhibits less deformation and shrinkage under high temperature conditions.

[0039] The ratio of the total mass of the cyclic olefin compound and the α-olefin compound to the total mass of the monomers constituting the cyclic olefin resin (A2) is preferably 70% by mass or more, more preferably 80% by mass or more, particularly preferably 90% by mass or more, and may also be 100% by mass, in order to obtain a resin composition that exhibits little deformation and shrinkage under high-temperature conditions and maintains high elongation even after being left for a long time under high-temperature conditions.

[0040] In the cyclic olefin resin (A2), the method for polymerizing the monomer and the method for adding hydrogen to the obtained polymer are not particularly limited and can be carried out by known methods. Polymerization may be random copolymerization or block copolymerization, but random copolymerization is preferred.

[0041] In the cyclic olefin resin (A2), the catalyst used when polymerizing the monomer is not particularly limited, and for example, Ziegler-Natta catalysts, metathesis catalysts, metallocene catalysts, etc., can be used. Among these, metallocene catalysts or Ziegler-Natta catalysts are preferred.

[0042] Examples of commercially available cyclic olefin resins (A) include, for example, TOPAS® (manufactured by Topas Advanced Polymers), Apel® (manufactured by Mitsui Chemicals), Zeonex® (manufactured by Nippon Zeon Co., Ltd.), Zeonor® (manufactured by Nippon Zeon Co., Ltd.), and Arton® (manufactured by JSR Corporation).

[0043] Linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst. Linear low-density polyethylene (B) may also be copolymerized with α-olefin compounds other than ethylene, such as butene, hexene, and octene.

[0044] The melt viscosity of linear low-density polyethylene (B) is not particularly limited, but for example, at a barrel temperature of 290°C and a shear rate of 122 sec. －１ The measured value may be 300 Pa·s or more, 350 Pa·s or more, or 400 Pa·s or more. It may also be 900 Pa·s or less, 850 Pa·s or less, or 800 Pa·s or less. The melt viscosity of linear low-density polyethylene (B) may be in the range of 300 to 900 Pa·s.

[0045] Furthermore, in order to further enhance the effect of minimizing deformation and shrinkage under high-temperature conditions and maintaining high elongation even after being left for a long time under high-temperature conditions, the melt viscosity of the linear low-density polyethylene (B) is preferably in the range of 1.0 to 2.0 times that of the cyclic olefin resin (A). More preferably, it is 1.2 times or more, and particularly preferably 1.5 times or more. Also, it is more preferably 1.8 times or less. The melt viscosity of both the cyclic olefin resin (A) and the linear low-density polyethylene (B) is as described above, at a barrel temperature of 290°C and a shear rate of 122 sec. －１ These are the values ​​measured at [location / location].

[0046] In resin composition (1), the ratio of cyclic olefin resin (A) to the total mass of cyclic olefin resin (A) and linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass. This ratio of the two materials results in a resin composition that exhibits minimal deformation and shrinkage under high-temperature conditions and maintains high elongation even after being left for extended periods under high-temperature conditions. Furthermore, the ratio of cyclic olefin resin (A) to the total mass of cyclic olefin resin (A) and linear low-density polyethylene (B) is preferably 32% by mass or more, more preferably 35% by mass or more, and particularly preferably 38% by mass or more. It is also preferably 48% by mass or less, more preferably 45% by mass or less, and particularly preferably 43% by mass or less.

[0047] The resin composition (1) may contain other components in addition to the cyclic olefin resin (A) and linear low-density polyethylene (B). Examples of other components include resin components such as cyclic olefin resins other than cyclic olefin resin (A), polyethylene resins other than linear low-density polyethylene (B), and other resins other than cyclic olefin resins and polyethylene resins, as well as additive components such as antioxidants, heavy metal stabilizers, ultraviolet absorbers, heat stabilizers, antistatic agents, flame retardants, colorants, and plasticizers.

[0048] In the resin composition (1), the ratio of cyclic olefin resin (A) to the total mass of cyclic olefin resins may be 80% by mass or more, 90% by mass or more, or 100% by mass. Similarly, the ratio of linear low-density polyethylene (B) to the total mass of polyethylene resins may be 80% by mass or more, 90% by mass or more, or 100% by mass. The ratio of the total mass of cyclic olefin resin (A) and linear low-density polyethylene (B) to the total mass of resin components in the resin composition (1) may be 80% by mass or more, 90% by mass or more, or 100% by mass.

[0049] The ratio of the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) to the total mass of the resin composition (1) may be 80% by mass or more, 90% by mass or more, or 95% by mass or more.

[0050] Regarding the additive components that the resin composition (1) may optionally contain, the ratio of each additive component to the total mass of the resin composition (1) may be in the range of 0 to 5% by mass. In particular, the content of hindered phenol-based antioxidants among the antioxidants is preferably in the range of 0 to 1% by mass, as this results in a resin composition with lower dielectric loss.

[0051] One embodiment of the resin composition comprises a cyclic olefin resin (C) and linear low-density polyethylene (D). When formed into a film under the following conditions, the linear low-density polyethylene (D) forms a sea phase and the cyclic olefin resin (C) forms an island phase in the central 200 μm range relative to the film thickness. This resin composition may be referred to as resin composition (2) below. Extruder: 20 mm diameter single-screw extruder Die: 150 mm wide coat hanger die, lip opening 0.35 mm Screw: L / D = 29 full-flight screw, compression ratio 2.9 Film formation temperature: Cylinder and die temperature 290°C Discharge rate: 2.3 kg / h Cooling roll temperature: 50°C Film thickness: 300 μm

[0052] In resin composition (2), when formed into a film under the above conditions, linear low-density polyethylene (D) forms a sea phase and cyclic olefin resin (C) forms ellipsoidal island phases in a 200 μm range from the center of the film thickness. This utilizes the excellent elongation characteristics of the linear low-density polyethylene (D) in the sea phase, while the cyclic olefin resin (C) present as island phases enhances heat resistance. As a result, the resin composition exhibits minimal deformation and shrinkage under high-temperature conditions and maintains high elongation even after being left for extended periods under high-temperature conditions.

[0053] The 200 μm center relative to the film thickness refers, in other words, to the area inside the 50 μm point from each of the two surfaces of a 300 μm thick film. The resin composition (2) only needs to be such that, when formed into a film under the above conditions, the linear low-density polyethylene (D) forms a sea phase and the cyclic olefin resin (C) forms an island phase in that range. The specific structure and properties of the cyclic olefin resin (C) and the linear low-density polyethylene (D), as well as other components contained in the resin composition (2), are not particularly limited.

[0054] The island phases formed by the cyclic olefin resin (C) may be ellipsoidal in shape, and their size and other characteristics are not particularly limited. In particular, it is preferable that the island phases of the cyclic olefin resin (C) have a minor axis in the range of 1 to 10 μm and a major axis in the range of 10 to 100 μm, as this results in a resin composition that exhibits little deformation and shrinkage under high-temperature conditions and maintains high elongation even after being left for a long time under high-temperature conditions. Furthermore, it is preferable that the ratio of the length of the major axis to the length of the minor axis is less than 10.

[0055] In the resin composition (2), from the viewpoint of easily adjusting the size of the island phase of the cyclic olefin resin (C) to the above preferred value, it is preferable that the melt viscosity of the linear low-density polyethylene (D) is in the range of 1.0 to 2.0 times the melt viscosity of the cyclic olefin resin (C). Furthermore, it is more preferable that it is 1.2 times or more, and particularly preferable that it is 1.5 times or more. Also, it is more preferable that it is 1.8 times or less. The melt viscosity of both the cyclic olefin resin (C) and the linear low-density polyethylene (D) is measured at a barrel temperature of 290°C and a shear rate of 122 sec. －１ These are the values ​​measured at [location / location].

[0056] The melt viscosity of the cyclic olefin resin (C) is such that it easily forms a sea-island structure, and at a barrel temperature of 290°C and a shear rate of 122 sec. －１The measured value is preferably 300 Pa·s or more, more preferably 350 Pa·s or more, and particularly preferably 400 Pa·s or more. Furthermore, it is preferably 600 Pa·s or less, more preferably 550 Pa·s or less, and particularly preferably 500 Pa·s or less. The melt viscosity of the cyclic olefin resin (C) may be in the range of 300 to 600 Pa·s.

[0057] Furthermore, the melt viscosity of linear low-density polyethylene (D) is such that it easily forms a sea-island structure, and at a barrel temperature of 290°C and a shear rate of 122 sec. －１ The measured value is preferably 500 Pa·s or more, more preferably 550 Pa·s or more, and particularly preferably 600 Pa·s or more. Furthermore, it is preferably 900 Pa·s or less, more preferably 850 Pa·s or less, and particularly preferably 800 Pa·s or less. The melt viscosity of linear low-density polyethylene (D) may be in the range of 500 to 900 Pa·s.

[0058] For cyclic olefin resins (C), it is preferable that the glass transition temperature (Tg) is in the range of 150 to 200°C, as this further enhances the effect of superior heat resistance.

[0059] Specific examples of cyclic olefin resins (C) include the following: Cyclic olefin resin (C1): Addition polymer of a cyclic olefin compound or its hydrogenated form Cyclic olefin resin (C2): Copolymer of monomers containing a cyclic olefin compound and an α-olefin compound or its hydrogenated form Cyclic olefin resin (C3): Ring-opening (co)polymer of a cyclic olefin compound or its hydrogenated form Cyclic olefin resin (C4): Cyclic olefin resins (A1) to (A3) with a polar group-containing unsaturated compound grafted, copolymerized, or grafted and copolymerized.

[0060] In the cyclic olefin resin (C), the details of the cyclic olefin compound, α-olefin compound, and unsaturated compound having a polar group are the same as those described in the description of the cyclic olefin resin (A). Among the cyclic olefin resins (C1) to (C4), when the resin composition is used as an insulating material for cables, cyclic olefin resins (C1) to (C3) are preferred from the viewpoint of dielectric constant. Furthermore, cyclic olefin resin (C2) is preferred in that it is a resin composition that exhibits little deformation and shrinkage under high temperature conditions and can maintain high elongation even after being left for a long time under high temperature conditions, and a copolymer of monomers containing a cyclic olefin compound and an α-olefin compound is even more preferred. The details of cyclic olefin resin (C2) are the same as those of cyclic olefin resin (A2).

[0061] Linear low-density polyethylene (D) is preferable to use a metallocene catalyst as the polymerization catalyst because it exhibits a more pronounced effect of superior elongation. Linear low-density polyethylene (D) may also be obtained by copolymerizing α-olefin compounds other than ethylene, such as butene, hexene, and octene.

[0062] In the resin composition (2), the mixing ratio of the cyclic olefin resin (C) and the linear low-density polyethylene (D) is not particularly limited, but from the viewpoint of easily forming a desired sea-island structure, it is preferable that the proportion of the cyclic olefin resin (C) to the total mass of both is greater than 30% by mass and less than 50% by mass. Furthermore, the proportion of the cyclic olefin resin (C) to the total mass of the cyclic olefin resin (C) and the linear low-density polyethylene (D) is preferably 32% by mass or more, more preferably 35% by mass or more, and particularly preferably 38% by mass or more. It is also preferably 48% by mass or less, more preferably 45% by mass or less, and particularly preferably 43% by mass or less.

[0063] The resin composition (2) may contain other components in addition to the cyclic olefin resin (C) and linear low-density polyethylene (D). Examples of other components include resin components such as polyethylene other than linear low-density polyethylene (D), cyclic olefin resins, and other resins other than polyethylene resins, as well as additive components such as antioxidants, heavy metal stabilizers, ultraviolet absorbers, heat stabilizers, antistatic agents, flame retardants, colorants, and plasticizers.

[0064] In resin composition (2), the ratio of linear low-density polyethylene (D) to the total mass of polyethylene may be 80% by mass or more, 90% by mass or more, or 100% by mass. The ratio of the total mass of cyclic olefin resin (C) and linear low-density polyethylene (D) to the total mass of resin components contained in resin composition (2) may be 80% by mass or more, 90% by mass or more, or 100% by mass.

[0065] The ratio of the total mass of the cyclic olefin resin (C) and the linear low-density polyethylene (D) to the total mass of the resin composition (2) may be 80% by mass or more, 90% by mass or more, or 95% by mass or more.

[0066] Regarding the additive components that the resin composition (2) may optionally contain, the ratio of each additive component to the total mass of the resin composition (2) may be in the range of 0 to 5% by mass. In particular, the content of hindered phenol-based antioxidants among the antioxidants is preferably in the range of 0 to 1% by mass, as this results in a resin composition with lower dielectric loss.

[0067] The resin material of one embodiment is a resin material comprising pellets (α) containing a cyclic olefin resin (A) and pellets (β) containing linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the pellets (α) and (β) are included such that the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass.

[0068] In the resin material, the cyclic olefin resin (A) and the linear low-density polyethylene (B) are the same as those described in resin composition (1).

[0069] The pellet (α) contains a cyclic olefin resin (A), but may also contain other components besides the cyclic olefin resin (A) and linear low-density polyethylene (B). Examples of other components include resin components such as cyclic olefin resins other than cyclic olefin resin (A), polyethylene other than linear low-density polyethylene (B), and other resins other than cyclic olefin resins and polyethylene, as well as additive components such as antioxidants, heavy metal stabilizers, ultraviolet absorbers, heat stabilizers, antistatic agents, flame retardants, colorants, and plasticizers.

[0070] The proportion of cyclic olefin resin (A) in pellet (α) may be 80% by mass or more, 90% by mass or more, 95% by mass or more, or 100% by mass. Regarding other components that pellet (α) may contain, the proportion of these other components in pellet (α) may be in the range of 0 to 5% by mass. In particular, since the content of hindered phenol antioxidants among the antioxidants results in a resin material with lower dielectric loss, it is preferable that the proportion of hindered phenol antioxidants in the total resin material be in the range of 0 to 1% by mass. Here, the total resin material refers to the sum of pellet (α), pellet (β), and other pellets that may be used as an option.

[0071] The pellets (β) contain linear low-density polyethylene (B), but may also contain other components besides cyclic olefin resin (A) and linear low-density polyethylene (B). Examples of other components include resin components such as cyclic olefin resins other than cyclic olefin resin (A), polyethylene other than linear low-density polyethylene (B), and other resins other than cyclic olefin resin and polyethylene, as well as additive components such as antioxidants, heavy metal stabilizers, ultraviolet absorbers, heat stabilizers, antistatic agents, flame retardants, colorants, and plasticizers.

[0072] The proportion of linear low-density polyethylene (B) in pellet (β) may be 80% by mass or more, 90% by mass or more, 95% by mass or more, or 100% by mass. Regarding other components that pellet (β) may contain, the proportion of other components in pellet (β) may be in the range of 0 to 5% by mass. In particular, since the content of hindered phenol-based antioxidants among the antioxidants results in a resin material with lower dielectric loss, it is preferable that the proportion of hindered phenol-based antioxidants in the total resin material be in the range of 0 to 1% by mass. As mentioned above, the total resin material refers to the sum of pellet (α), pellet (β), and other pellets that may be used as an option.

[0073] The resin material may contain other pellets besides pellets (α) and pellets (β). These other pellets may include components other than cyclic olefin resin (A) and linear low-density polyethylene (B), such as resin components including cyclic olefin resins other than cyclic olefin resin (A), polyethylene other than linear low-density polyethylene (B), and other resins other than cyclic olefin resin and polyethylene, as well as additive components such as antioxidants, heavy metal stabilizers, ultraviolet absorbers, heat stabilizers, antistatic agents, flame retardants, colorants, and plasticizers.

[0074] The ratio of the total mass of pellets (α) and pellets (β) to the total mass of the resin material may be 80% by mass or more, 90% by mass or more, 95% by mass or more, or 100% by mass.

[0075] The resin material contains pellets (α) and pellets (β) such that the ratio of cyclic olefin resin (A) to the total mass of cyclic olefin resin (A) and linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass. Furthermore, the ratio of cyclic olefin resin (A) to the total mass of cyclic olefin resin (A) and linear low-density polyethylene (B) is preferably 32% by mass or more, more preferably 35% by mass or more, and particularly preferably 38% by mass or more. It is also preferably 48% by mass or less, more preferably 45% by mass or less, and particularly preferably 43% by mass or less.

[0076] The uses of the resin compositions (1) and (2) and the resin material are not particularly limited and can be used in a variety of applications, such as various molded articles. The shape of the molded article is not particularly limited and may be in the form of a film or have a three-dimensional structure. The molding method is also not particularly limited and may be injection molding, extrusion molding, etc. If the molded article is in the form of a film, it may be melt extrusion using an extruder, vacuum pressing using a hot vacuum press, casting, etc. Since the resin compositions (1) and (2) and the resin material exhibit little deformation and shrinkage under high temperature conditions and maintain high elongation even after being left for a long time under high temperature conditions, they can be suitably used in medical applications sterilized by autoclave, food packaging applications sterilized by retort, etc. Furthermore, because they have the characteristic of low dielectric loss inherent in cyclic olefin resins, they can be suitably used as insulating materials for cables.

[0077] The type of cable is not particularly limited, but it can be suitably used not only for general communication cables but also for applications requiring particularly high heat resistance, such as automotive cables. The shape of the cable is not particularly limited, but coaxial cables are a commonly used example. Coaxial cables using the resin compositions (1) and (2) and the resin material can be manufactured by general methods such as extrusion.

[0078] Examples of embodiments of the present disclosure are given below. The present disclosure is not limited to the following embodiments. <1> A resin composition comprising a cyclic olefin resin (A) and linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass.

[0079] <2> The resin composition according to <1>, wherein the cyclic olefin resin (A) is a copolymer of monomers containing a cyclic olefin compound and an α-olefin compound.

[0080] <3> The resin composition according to <1> or <2>, wherein the ratio of the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) to the total mass of the resin components in the resin composition is 80% by mass or more.

[0081] <4> The resin composition according to any one of <1> to <3> above, wherein the content of the hindered phenol antioxidant is in the range of 0 to 1% by mass.

[0082] <5> A resin composition comprising a cyclic olefin resin (C) and linear low-density polyethylene (D), wherein when formed into a film under the following conditions, the linear low-density polyethylene (D) forms a sea phase and the cyclic olefin resin (C) forms an island phase in the central 200 μm range relative to the film thickness. Extruder: 20 mm diameter single-screw extruder Die: 150 mm wide coat hanger die, lip opening 0.35 mm Screw: L / D = 29 full-flight screw, compression ratio 2.9 Film formation temperature: Cylinder and die temperature 290°C Discharge rate: 2.3 kg / h Cooling roll temperature: 50°C Film thickness: 300 μm

[0083] <6> The resin composition according to <5>, wherein the size of the island phase of the cyclic olefin resin (C) is in the range of 1 to 10 μm for the short axis and in the range of 10 to 100 μm for the long axis.

[0084] <7> A resin material comprising pellets (α) containing a cyclic olefin resin (A) and pellets (β) containing linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the pellets (α) and (β) are included such that the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass.

[0085] <8> A molded article comprising the resin composition described in any one of <1> to <6> above or the resin material described in <7> above.

[0086] <9> An insulating material for communication cables comprising the resin composition described in any one of <1> to <6> above or the resin material described in <7> above.

[0087] <10> An insulating material for automotive cables comprising the resin composition described in any one of <1> to <6> above or the resin material described in <7> above.

[0088] <11> A communication cable including an insulating layer formed using the insulating material for communication cables described in <9> above.

[0089] <12> An in-vehicle cable comprising an insulating layer formed using the insulating material for in-vehicle cables described in <10> above.

[0090] The embodiment will be described in more detail below with reference to examples, but this embodiment is not limited to the following examples.

[0091] [Measurement of Glass Transition Temperature (Tg) of Resin] Measurement was performed by differential scanning calorimetry (DSC) under the following conditions, in accordance with ISO 11357-1, -2, -3. Sample amount: 7.5 to 11.0 mg Temperature profile: Heating from 40°C to 250°C at 20°C / min, isothermal holding at 250°C for 2 minutes, cooling from 250°C to 40°C at 20°C / min, isothermal holding at 40°C for 5 minutes, heating from 40°C to 250°C at 20°C / min, cooling from 250°C to 40°C at 80°C / min Analysis conditions: Data from the second heating process was used. Midpoint was used for the glass transition temperature (Tg).

[0092] [Measurement of Melt Viscosity of Resin] Using a capillary graph manufactured by Toyo Seiki Seisakusho Co., Ltd., a flat die of 1 mmφ × 10 mmL was used as the capillary, with a barrel temperature of 290°C and a shear rate of 122 sec. －１ The melt viscosity was measured under the following conditions.

[0093] [Details of each component used in the examples and comparative examples] ・Cyclic olefin resin (COC): Manufactured by Topas Advanced Polymers, norbornene-ethylene copolymer, "TOPAS 6015S-04", glass transition temperature (Tg) 158°C, melt viscosity 452 Pa·s ・Linear low-density polyethylene (m-LLDPE1): Manufactured by Tosoh Corporation, Nipolon-Z HF211R, melt viscosity 722 Pa·s, using metallocene catalyst as polymerization catalyst ・Linear low-density polyethylene (m-LLDPE2): Manufactured by Tosoh Corporation, Nipolon-Z HF310R, melt viscosity 385 Pa·s, using metallocene catalyst as polymerization catalyst ・Linear low-density polyethylene (LLDPE): Manufactured by Tosoh Corporation, LUMITEC 22-7, melt viscosity 585 Pa·s, without metallocene catalyst as polymerization catalyst: Low-density polyethylene (LDPE): Tosoh Corporation, Petrocene 180R, melt viscosity 264 Pa·s; High-density polyethylene (HDPE): Tosoh Corporation, Nipolon Hard 4030, melt viscosity 350 Pa·s; Hindered phenolic antioxidant: BASF Japan Ltd., "IRGANOX 1010", containing tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane as a phenolic compound.

[0094] [Examples 1-4 and Comparative Examples 1-6] Resin compositions were prepared by blending each component in the proportions shown in Table 1 below. Using the obtained resin compositions, films with a thickness of 300 μm were produced in an extruder under the following conditions. No intentional stretching was performed. The obtained films were subjected to the following evaluation tests. The results are shown in Table 1.

[0095] [Film Production Conditions] Extruder: 20mm diameter single-screw extruder (manufactured by Toyo Seiki Seisakusho Co., Ltd.) Die: 150mm wide coat hanger die, lip opening 0.35mm Screw: L / D = 29 full-flight screw, compression ratio 2.9 Film formation temperature: Cylinder and die temperature 290℃ Discharge rate: 2.3 kg / h (adjusted so that the discharge rate is 2.3 kg / h with screw rotation speed at 65-70 rpm) Take-up speed: Approximately 1.1-1.2 m / min (adjusted so that the film thickness is 300 μm) Cooling roll temperature: 50℃ (set temperature of the device) Film thickness: 300 μm

[0096] [Measurement of Tensile Strength and Nominal Tensile Strain at Breaking] For Examples 1 and 2 and Comparative Examples 1 to 6, dumbbell-shaped test specimens with a total length of 115 mm and a thickness of 300 μm were cut from the previously obtained film in accordance with JIS K7127. Two test specimens were prepared: one with the length direction of the dumbbell oriented in the MD direction of the film, and another with the length direction of the dumbbell oriented in the TD direction. The nominal tensile strain at breaking (MD) and (TD) were measured in accordance with JIS K7161.

[0097] [Preliminary Heat Resistance Test] For Examples 1 and 2 and Comparative Examples 1 to 6, dumbbell-shaped test specimens (test specimen type 5) with a total length of 115 mm and a thickness of 300 μm were cut from the previously obtained film in accordance with JIS K7127. Two types of test specimens were prepared: one with the length of the dumbbell oriented in the MD direction of the film, and another with the length of the dumbbell oriented in the TD direction. The dumbbell-shaped test specimens were suspended vertically by pinching one end of the gripping tab, and a heat resistance test was performed for 30 minutes in a constant temperature oven (PHH-102, manufactured by ESPEC Corporation) set to 125°C. The dimensional and shape changes of the dumbbell-shaped test specimens after the test were checked and evaluated according to the following criteria. Note that the tensile fracture nominal strain measurement after heat treatment, described later, was performed only for specimens that received an A rating in the heat resistance test. A: In both test specimens, the longitudinal deformation of the dumbbell shape is ±0.5 mm or less, and there is almost no shape change such as waviness. B: In at least one of the two test specimens, the longitudinal deformation of the dumbbell shape is ±0.5 mm or more, or shape change such as waviness is observed, or both.

[0098] [Measurement of Tensile Nominal Strain at Fracture after Heat Treatment] For Examples 1 and 2 and Comparative Example 1, dumbbell-shaped test specimens with a total length of 115 mm and a thickness of 300 μm were cut from the previously obtained film in accordance with JIS K7127. The length direction of the dumbbell-shaped test specimen was aligned with the MD direction of the film. The test specimens were heat-treated in a vacuum dryer (VOS-301SD, manufactured by Tokyo Rikakikai Co., Ltd.) set to 125°C, and the tensile nominal strain at fracture (MD) of the test specimens was measured after 72 hours and after 1000 hours of treatment. The test specimen of Comparative Example 1 fractured at the time of the test after 1000 hours.

[0099] [Observation of Film Cross-Sectional Images] For Examples 1 and 2 and Comparative Example 1, test pieces were cut from the center of the previously obtained films and frozen and fractured in liquid nitrogen. After freezing and fracture, the test pieces were immersed in cyclohexanone to selectively dissolve and remove the cyclic olefin resin. Next, the test pieces were washed by immersion in isopropanol and vacuum-dried to obtain processed films for scanning electron microscopy observation. The cross-sections of the processed films for scanning electron microscopy observation in the MD and TD directions were observed using a scanning electron microscope. Figure 1 shows the scanning electron microscope image of the processed film for scanning electron microscopy observation of Example 1, Figure 2 shows the scanning electron microscope image of the processed film for scanning electron microscopy observation of Example 2, and Figure 3 shows the scanning electron microscope image of the processed film for scanning electron microscopy observation of Comparative Example 1.

[0100] [Dielectric Properties of Films] For the films of Examples 1, 3, and 4, the relative permittivity and dielectric loss tangent at 5 GHz and 15 GHz were measured at 23°C using a split-post dielectric resonator (SPDR) with a Keysight Technologies P9374A vector network analyzer.

[0101]

[0102] As shown in Table 1, the resin compositions of Examples 1 and 2 exhibited minimal deformation and shrinkage under high-temperature conditions and maintained high elongation even after being left for extended periods under high-temperature conditions. In particular, Example 1, which used m-LLDPE1 with high melt viscosity as the linear low-density polyethylene (B), showed a higher tensile fracture nominal strain in the TD direction. Comparative Example 1, in which the ratio of cyclic olefin resin (A) to the total mass of cyclic olefin resin (A) and linear low-density polyethylene (B) was 50% by mass or more, showed lower resistance to heat treatment compared to Examples 1 and 2, and fracture occurred prematurely. Comparative Examples 2 to 6, which used polyethylene that did not meet the requirements of linear low-density polyethylene (B) instead of linear low-density polyethylene (B), showed very low tensile fracture nominal strain values, low heat resistance, and significant deformation after 30 minutes of treatment at 125°C. Examples 3 and 4 are examples in which a hindered phenol-based antioxidant is included in the resin composition. However, since the content of the hindered phenol-based antioxidant is 1% by mass or less, both the dielectric constant and dielectric loss tangent are low, making them suitable for use as insulating materials for cables.

[0103] Although the present invention has been described with reference to several embodiments described above, the present invention is not limited to these embodiments. Various modifications can be made to the structure and details of the present invention within the scope of the invention. This disclosure is related to the subject matter described in Japanese Patent Application No. 2024-204027, filed on 22 November 2024, all of which are incorporated herein by reference.

Claims

1. A resin composition comprising a cyclic olefin resin (A) and linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass.

2. The resin composition according to claim 1, wherein the cyclic olefin resin (A) is a copolymer of monomers containing a cyclic olefin compound and an α-olefin compound.

3. The resin composition according to claim 1, wherein the ratio of the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) to the total mass of the resin components in the resin composition is 80% by mass or more.

4. The resin composition according to claim 1, wherein the content of the hindered phenol antioxidant is in the range of 0 to 1% by mass.

5. A resin composition comprising a cyclic olefin resin (C) and linear low-density polyethylene (D), wherein, when formed into a film under the following conditions, the linear low-density polyethylene (D) forms a sea phase and the cyclic olefin resin (C) forms an island phase in the central 200 μm range relative to the thickness of the film. Extruder: 20mm diameter single-screw extruder; Die: 150mm wide coat hanger die, lip opening 0.35mm; Screw: L / D = 29 full-flight screw, compression ratio 2.9; Film deposition temperature: Cylinder and die temperature 290°C; Discharge rate: 2.3 kg / h; Cooling roll temperature: 50°C; Film thickness: 300 μm 6. The resin composition according to claim 5, wherein the size of the island phase of the cyclic olefin resin (C) is in the range of 1 to 10 μm for the short axis and in the range of 10 to 100 μm for the long axis.

7. A resin material comprising pellets (α) containing a cyclic olefin resin (A) and pellets (β) containing linear low-density polyethylene (B), wherein the glass transition temperature (Tg) of the cyclic olefin resin (A) is in the range of 150 to 200°C, the linear low-density polyethylene (B) uses a metallocene catalyst as a polymerization catalyst, and the pellets (α) and (β) are included such that the ratio of the cyclic olefin resin (A) to the total mass of the cyclic olefin resin (A) and the linear low-density polyethylene (B) is greater than 30% by mass and less than 50% by mass.

8. A molded article comprising the resin composition according to any one of claims 1 to 6 or the resin material according to claim 7.

9. An insulating material for a communication cable comprising the resin composition according to any one of claims 1 to 6 or the resin material according to claim 7.

10. An insulating material for automotive cables comprising the resin composition according to any one of claims 1 to 6 or the resin material according to claim 7.

11. A communication cable comprising an insulating layer formed using the insulating material for communication cables described in claim 9.

12. An in-vehicle cable comprising an insulating layer formed using the insulating material for in-vehicle cables described in claim 10.

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