JP6362929B2 - tire - Google Patents

Description

  The present invention relates to a tire mounted on a rim, and particularly relates to a tire including a resin in at least a part of an exterior member.

  Conventionally, a tire in which an exterior member such as a tread using rubber is attached to a tire skeleton including a resin has been proposed (see, for example, Patent Document 1). Conventionally, a method using an adhesive has been used as a means for bonding the exterior member to the tire frame.

JP 2012-46032 A

When resin is used for both or one of the tire frame body and the tire exterior member, various resins can be selected as the resin, while the selected material exhibits the performance required for each member. Is required.
In addition, when using an adhesive to fix a tread or other exterior member to the tire frame body, the performance required for a tire is demonstrated in consideration of the compatibility between the material used for both members and the adhesive. A possible adhesive must be selected. However, when a resin is used for the tire frame body or the exterior member, since the properties and compatibility differ depending on the resin used, it is not always easy to select an adhesive between the members. For example, when an olefinic thermoplastic resin is used for a tire frame, it is difficult to select an adhesive for sufficiently fixing the exterior member to the tire frame, and there is still room for improvement in fixing both members.
Furthermore, when both members are fixed with an adhesive, an adhesive application step is required. For this reason, if the application | coating process of an adhesive agent can be abbreviate | omitted, the efficiency of the manufacturing process of a tire can further be improved.

  In view of the above circumstances, an object of the present invention is to provide a tire that can be easily manufactured because the exterior member is unlikely to peel from the tire frame.

[1] An annular tire skeleton formed of a material including at least one selected from a diene rubber and a polyolefin-based thermoplastic resin elastomer; and ethylene propylene rubber; and at least a part of the tire skeleton directly An exterior member that is in contact with and includes ethylene propylene rubber.
[2] The tire according to [1], wherein the polyolefin-based thermoplastic resin elastomer is a copolymer of polypropylene and polyethylene.
[3] The exterior member tire according to [1] or [2] containing only the ethylene propylene rubber.
[4] The content of the ethylene propylene rubber in the tire skeleton is based on a total amount of 100 parts by mass of at least one kind selected from the diene rubber and the polyolefin thermoplastic elastomer in the tire skeleton. The tire according to any one of [1] to [3] , which is 10 to 30 parts by mass.

  ADVANTAGE OF THE INVENTION According to this invention, the exterior member is hard to peel from a tire frame body, and the tire which can be manufactured easily can be provided.

(A) is a perspective view showing a section of a part of the tire concerning a 1st embodiment, and (B) is a sectional view of a bead part with which a rim was equipped. It is sectional drawing along the tire rotating shaft which shows the state by which the reinforcement cord was embed | buried under the crown part of the tire case of the tire of 1st Embodiment. It is a perspective view showing a section of some tires concerning a 2nd embodiment.

[tire]
The tire of the present invention is formed of a material including at least one selected from diene rubbers and thermoplastic resin elastomers; and ethylene propylene rubber (hereinafter also referred to as “resin material”) and is an annular tire skeleton. And an exterior member that is in direct contact with the tire frame and includes ethylene propylene rubber.

  In the tire of the present invention, ethylene propylene rubber is contained in both the tire frame body and the exterior member. Furthermore, in the tire of the present invention, the tire frame body and the exterior member are in direct contact with each other at least partially. The tire of the present invention has a configuration in which the exterior member is difficult to peel off from the tire skeleton because the exterior member is attached at a portion (interface) in direct contact with the tire skeleton. The reason why adhesive force is generated at the interface between the tire frame body and the exterior member is not clear, but the ethylene propylene rubber contained in the tire frame body becomes an island part of the sea-island structure, and is an island composed of the ethylene propylene rubber. It is presumed that the part and the ethylene propylene rubber contained in the exterior member are compatible and integrated at the interface, thereby exhibiting the same effect as the so-called anchor effect. Furthermore, since the ethylene propylene rubber contained in the tire frame body and the ethylene propylene rubber contained in the exterior member have the same or similar structure, an adhesive force is generated between the two members by exerting an interaction. It is also speculated.

  In the tire of the present invention, a tire skeleton and an exterior member can be formed by injection molding. In particular, when a thermoplastic resin elastomer is used as a material constituting the tire frame body, the tire frame body can be formed more easily by injection molding. At this time, according to the tire of the present invention, the exterior member can be adhered on the tire frame at a relatively low temperature. For this reason, for example, even when a vulcanization step is performed after injection molding, it is possible to prevent the EPDM in the exterior member from being vulcanized at the time of injection molding or mounting on a tire frame body. . Further, the tire of the present invention can adhere the exterior member to the tire frame body without providing an adhesive layer. For this reason, in the manufacturing process of the tire of this invention, the process of apply | coating an contact bonding layer can also be skipped, and it is excellent in production efficiency.

《Tire skeleton body》
The tire is a tire skeleton using a resin material containing at least one selected from diene rubbers and thermoplastic resin elastomers (hereinafter sometimes referred to as “first component”) and ethylene propylene rubber. Have

In the present specification, “resin” is a concept including a thermoplastic resin and a thermosetting resin, but does not include vulcanized rubber such as natural rubber and synthetic rubber. Further, “rubber” is a polymer compound having elasticity, but in this specification, it is distinguished from a thermoplastic resin elastomer. “Thermoplastic resin elastomer” is a polymer compound having elasticity, a crystalline polymer having a high melting point or a hard segment having a high cohesive force, and an amorphous glass transition temperature. It means a thermoplastic resin material comprising a copolymer having a polymer constituting a low soft segment. In the thermoplastic resin elastomer, the hard segment behaves as a pseudo crosslinking point and develops elasticity (so-called physical crosslinking). On the other hand, rubber has a double bond in the molecular chain, and is crosslinked (vulcanized) by adding sulfur or the like to generate a three-dimensional network structure and develop elasticity (chemical crosslinking). . For this reason, the thermoplastic resin elastomer can be reused after recovery because the hard segment is melted by heating and a pseudo crosslinking point is formed again by cooling.

<First component>
In the present invention, at least one selected from diene rubbers and thermoplastic resin elastomers can be used as the first component. As the first component, it is preferable to use a thermoplastic resin elastomer from the viewpoint of compatibility with ethylene propylene rubber and injection moldability. In particular, from the viewpoint of having a structure similar to ethylene propylene rubber, it is more preferable to use a polyolefin-based thermoplastic resin elastomer. As the first component, one selected from diene rubbers and thermoplastic resin elastomers may be used alone, or two or more may be used in combination as appropriate.
The content of the first component in the tire frame body is preferably 50% by mass to 90% by mass, and preferably 60% by mass to 90% by mass from the viewpoint of the elastic modulus and strength of the tire frame body. Is more preferable, and it is especially preferable that it is 70 mass%-90 mass%.

(Diene rubber)
The diene rubber that can be used for the tire frame is not particularly limited. For example, natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene copolymer rubber (SBR). ), Acrylonitrile-butadiene copolymer rubber (NBR).

  The diene rubber may be a vulcanized rubber. The rubber may be vulcanized by a known method, for example, by the methods described in JP-A-11-048264, JP-A-11-029658, JP-A-2003-238744, and the like. . For rubber vulcanization, for example, a reinforcing material such as carbon black, a filler, a vulcanizing agent, a vulcanization accelerator, a fatty acid or a salt thereof, a metal oxide, a process oil, an antiaging agent, and the like are appropriately blended with the rubber. And after kneading | mixing using a Banbury mixer, it can carry out by heating.

(Thermoplastic resin elastomer)
Examples of the thermoplastic resin elastomer that can be used for the tire skeleton include polyamide-based thermoplastic resin elastomers, polyurethane-based thermoplastic resin elastomers, polyester-based thermoplastic resin elastomers, and polyolefin-based thermoplastic resin elastomers. As described above, it is preferable to use a polyolefin-based thermoplastic resin.

-Polyolefin thermoplastic elastomer-
The polyolefin-based thermoplastic resin elastomer is a hard segment having at least a crystalline polyolefin and a high melting point, and other polymers (for example, the polyolefin, other polyolefins, and polyvinyl compounds) are amorphous and have a low glass transition temperature. It means a material constituting a soft segment, and examples thereof include a polyolefin-based thermoplastic elastomer (TPO) defined in JIS K6418: 2007.

  Examples of the polyolefin forming the hard segment include polyethylene, polypropylene, isotactic polypropylene, polybutene, and the like. Examples of the soft segment of the polyolefin-based thermoplastic resin elastomer include polyolefin and polyvinyl compounds. For example, ethylene propylene rubber such as EPM and EPDM may be used as the soft segment.

Examples of the polyolefin-based thermoplastic resin elastomer include olefin-α-olefin random copolymers, olefin block copolymers, and the like. For example, propylene block copolymers, ethylene-propylene copolymers, propylene-1-hexene. Copolymer, propylene-4-methyl-1-pentene copolymer, propylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-4-methyl-pentene copolymer, ethylene-1-butene Copolymer, 1-butene-1-hexene copolymer, 1-butene-4-methyl-pentene, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer , Ethylene-butyl methacrylate copolymer, ethylene-methyl acrylate copolymer Ethylene-ethyl acrylate copolymer, ethylene-butyl acrylate copolymer, propylene-methacrylic acid copolymer, propylene-methyl methacrylate copolymer, propylene-ethyl methacrylate copolymer, propylene-butyl methacrylate copolymer , Propylene-methyl acrylate copolymer, propylene-ethyl acrylate copolymer, propylene-butyl acrylate copolymer, ethylene-vinyl acetate copolymer, propylene-vinyl acetate copolymer, and the like.
The polyolefin content in the polyolefin-based thermoplastic resin elastomer is preferably 50% by mass or more and 100% by mass or less.

  The polyolefin-based thermoplastic resin elastomer is preferably a homopolymer of polypropylene or polyethylene, or a copolymer of polypropylene and polyethylene (ethylene-propylene copolymer). The copolymer of polypropylene and polyethylene includes a random copolymer and a block copolymer, and is preferably a random copolymer from the viewpoint of injection moldability.

The number average molecular weight of the polyolefin-based thermoplastic resin elastomer is preferably 5,000 to 10,000,000. When the number average molecular weight of the polyolefin-based thermoplastic resin elastomer is 5,000 to 10,000,000, the mechanical properties of the thermoplastic resin material are sufficient, and the processability is also excellent. From the same viewpoint, the number average molecular weight of the polyolefin-based thermoplastic resin elastomer is more preferably 7,000 to 1,000,000, and particularly preferably 10,000 to 1,000,000. Thereby, the mechanical properties and workability of the thermoplastic resin material can be further improved.
From the viewpoint of moldability, the mass ratio (x: y) of the hard segment (x) to the soft segment (y) in the polyolefin-based thermoplastic resin elastomer is preferably 50:50 to 95: 5, and 50:50 ~ 90: 10 is more preferred.

  The polyolefin-based thermoplastic resin elastomer can be synthesized by copolymerization by a known method.

Examples of the polyolefin-based thermoplastic resin elastomer include, for example, commercially available “Tuffmer” series manufactured by Mitsui Chemicals (for example, A0550S, A1050S, A4050S, A1070S, A4070S, A35070S, A1085S, A4085S, A7090, A70090, MH7007, MH7010). , XM-7070, XM-7080, BL4000, BL2481, BL3110, BL3450, P-0275, P-0375, P-0775, P-0180, P-0280, P-0480, P-0680), Mitsui DuPont Poly Chemical Corporation "Nuclerel" series (for example, AN4214C, AN4225C, AN42115C, N0903HC, N0908C, AN42012C, N410, N1050H, N1108 N1110H, N1207C, N1214, AN4221C, N1525, N1560, N0200H, AN4228C, AN4213C, N035C, “Elvalloy AC” series (eg, 1125AC, 1209AC, 1218AC, 1609AC, 1820AC, 1913AC, 2112AC, 2116AC, 2615AC, 2715AC, 3117 3427AC, 3717AC), Sumitomo Chemical Co., Ltd. “Aclift” series, “Evertate” series, Tosoh Corporation “Ultrasen” series, and the like.
Furthermore, examples of the polyolefin-based thermoplastic resin elastomer include, for example, “Prime TPO” series (for example, E-2900H, F-3900H, E-2900, F-3900, J-manufactured by Prime Polymer Co., Ltd.). 5710, J-5900, E-2910, F-3910, J-5910, E-2710, F-3710, J-5910, E-2740, F-3740, R110MP, R110E, T310E, M142E, etc.) are also used. be able to.

-Acid modification of polyolefin-based thermoplastic resin elastomers-
As the polyolefin-based thermoplastic resin elastomer, for example, a polyolefin-based thermoplastic resin elastomer having an acid group (acid-modified polyolefin-based thermoplastic resin elastomer) can also be used.
When a tire skeleton is formed using the acid-modified polyolefin-based thermoplastic resin elastomer, the reinforcing cord is wound directly around the outer periphery of the tire skeleton, or the reinforcing cord layer reinforced the reinforcing cord around the outer periphery of the tire skeleton. In the case where it is formed by being embedded in, the adhesion with the reinforcing cord can be improved.

Examples of the acidic group possessed by the acid-modified polyolefin-based thermoplastic resin elastomer include a carboxylic acid group, a sulfuric acid group, and a phosphoric acid group, which are weak acid groups, from the viewpoint of suppressing deterioration of the thermoplastic resin material. Is particularly preferred.
Here, “acid-modified” refers to bonding an unsaturated compound having an acidic group such as a carboxylic acid group, a sulfuric acid group, or a phosphoric acid group to an olefinic thermoplastic resin elastomer. For example, when an unsaturated carboxylic acid (generally maleic anhydride) is used as an unsaturated compound having an acidic group, an unsaturated bond site of the unsaturated carboxylic acid is bonded to the olefinic thermoplastic elastomer (for example, , Graft polymerization).

In general, acid modification of a polyolefin-based thermoplastic resin elastomer is performed using a twin screw extruder or the like, and an olefin-based thermoplastic resin elastomer, an unsaturated compound having an acidic group (for example, an unsaturated carboxylic acid), and an organic peroxide. It can be carried out by kneading and graft copolymerization. The addition amount of the unsaturated compound having an acidic group is preferably 0.1 part by mass to 20 parts by mass, more preferably 0.5 part by mass to 10 parts by mass with respect to 100 parts by mass of the olefinic thermoplastic resin elastomer. .
If the amount of the unsaturated compound having an acidic group is too small, the amount of grafting to the olefinic thermoplastic resin elastomer is lowered. On the other hand, if the amount added is excessive, the amount of unreacted unsaturated carboxylic acid in the resin increases, and sufficient adhesive strength cannot be obtained, resulting in poor workability.
The organic peroxide may be added in an amount sufficient to carry out the grafting reaction. For example, 0.01 to 5 parts by weight is preferable, and 0.03 to 1 part by weight is further added. preferable.
Examples of the organic peroxide include 1,1 bis (t-butylperoxy) cyclohexane, 2,2bis (4,4-di-t-butylperoxycyclohexyl) propane, 1,1-bis (t -Butylperoxy) cyclododecane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5 dimethyl-2,5 -Di (benzoylperoxy) hexane, t-butylperoxyacetate, 2,2-bis (t-butylperoxy) butene, t-butylperoxybenzoate, n-butyl-4,4-bis (t-beroxy) ) Valerate, di-t-butylberoxyisophthalate, dicumyl peroxide, α-α'-bis (t-butylperoxide) X-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 1,3-bis (t-butylperoxydiisopropyl) benzene, t-butylcumyl peroxide, Di-t-butyl peroxide, p-menthane hydroperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, di-3-methoxybutyl peroxydicarbonate, di- 2-ethylhexyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, diisopropyl peroxydicarbonate, t-butyl peroxyisopropyl carbonate, dimyristyl peroxycarbonate, 1,1,3,3- Tetramethyl butyl neodecanoate, α-kumi Peroxy neodecanoate, t- butyl peroxy neodecanoate and the like, may be used in combination of two or more may be used these alone.

Examples of the acid-modified polyolefin-based thermoplastic resin elastomer include those obtained by graft-polymerizing acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc. to an olefin-based thermoplastic resin elastomer. In particular, it is preferable to use maleic anhydride.
Examples of the acid-modified polyolefin-based thermoplastic resin elastomer include commercially available “Tuffmer” series (MA8510, MH7007, MH7010, MA7020, MP0610, MP0620, etc.) manufactured by Mitsui Chemicals, Inc., “Admer” series (for example, LB548, QB510, QF500, QF551, QE060, QE840, NE065, etc.) can be used.

(Ethylene propylene rubber)
The tire frame includes ethylene propylene rubber together with the first component described above. The ethylene-propylene rubber includes a rubbery copolymer (EPDM) of ethylene, propylene, and a diene compound, or a rubbery copolymer (EPM) of ethylene and propylene, and a modified product thereof (for example, maleic acid). Modified ethylene propylene rubber) is also included.

Examples of the diene compound contained in EPDM include ethylidene norbornene (ENB), 1,4 hexadiene (1,4-HD), dicyclopentadiene (DCP), and the like. Examples of the modified ethylene propylene rubber include maleic acid-modified EPDM. The maleic acid-modified EPDM can be obtained by treating EPDM with maleic anhydride.
As the ethylene propylene rubber contained in the tire frame, EPDM or a modified product thereof is preferable from the viewpoint of easily increasing the strength by vulcanization.

  The number average molecular weight of the ethylene propylene rubber is preferably 100,000 to 300,000, more preferably 120,000 to 160,000 from the viewpoint of injection moldability. The ethylene propylene rubber is not particularly limited, and for example, commercially available product “EPT X-3012P” manufactured by Mitsui Chemicals, Inc. can be used. The ethylene propylene rubber contained in the tire skeleton may be used alone or in combination of two or more as appropriate. However, it is preferable that the ethylene propylene rubber contained in the tire skeleton is appropriately selected from the viewpoint of compatibility with the ethylene propylene rubber used for the exterior member described later.

  The content of the ethylene propylene rubber in the tire frame body is not particularly limited, but from the viewpoint of sufficiently exerting the effects of the present invention, the total amount of the first component in the tire frame body is 100 parts by mass. The amount is preferably 10 parts by mass or more. Further, as described later, in order to form a so-called sea-island structure in which ethylene propylene rubber is dispersed as a dispersed phase (domain), and from the viewpoint of the tensile elastic modulus and strength of the tire frame, the inclusion of ethylene propylene rubber in the tire frame The amount is preferably 10 parts by mass to 30 parts by mass, more preferably 10 parts by mass to 25 parts by mass with respect to 100 parts by mass of the total amount of the first component in the tire frame body, and 15 parts by mass. It is especially preferable that it is -25 mass parts.

  Moreover, a compatibilizing agent of the first component and ethylene propylene rubber can also be used for the tire frame body. The compatibilizer may have a function of bringing the surface energy between layers close to each other, or may have a reactive functional group. As the reactive group, a carbonyl group, a halogen group, a hydroxyl group, an amino group, an epoxy group, or the like is preferably used. The main compatibilizers include maleic acid-modified polyolefin, polymer obtained by graft polymerization of acrylic acid or glycidyl methacrylate to polyolefin, block copolymer of polyolefin and nylon, maleic acid of styrene-ethylene-butadiene-styrene copolymer Examples include modified products.

  In the present invention, the first component contained in the tire frame and the ethylene propylene rubber are composed of the ethylene propylene rubber forming the discontinuous phase in the matrix of the first component forming the continuous phase as the dispersed phase (domain). It is preferable to have a dispersed so-called sea-island structure. As described above, when the tire frame has a sea-island structure in which the first component forms a matrix (sea phase) and ethylene propylene rubber becomes a domain (island phase), the tire frame and exterior member The adhesion force can be further increased.

  The fact that the island phase containing ethylene propylene rubber is finely dispersed in the sea phase containing the first component can be confirmed by photographic observation using an SEM (scanning electron microscope).

  The first component and the ethylene propylene rubber can be kneaded using a known method. As a kneading machine that can be used for the kneading, for example, a screw extruder, a kneader, a Banbury mixer, a biaxial kneading extruder, or the like can be used.

(Other additives)
For the tire frame body, various fillers (for example, silica, calcium carbonate, clay), anti-aging agents, vulcanizing agents, vulcanization accelerators, metal oxides, process oils, plasticizers are used depending on the materials used. Various additives such as a colorant, a weathering agent, and a reinforcing material may be contained. The content of the additive in the resin material (tire frame) is not particularly limited, and can be appropriately used as long as the effects of the present invention are not impaired.
As specific examples of the various additives described above, examples of the antiaging agent include the antiaging agents described in International Publication WO2005 / 063482. Specifically, for example, naphthylamines such as phenyl-2-naphthylamine and phenyl-1-naphthylamine, 4,4′-α, α-dimethylbenzyl) diphenylamine, p- (P-toluene sulfonylamide) -diphenylamine, etc. Amine antioxidants such as diphenylamine, N, N′-diphenyl-p-phenylenediamine, p-phenylenediamine such as N-isopropyl-N′-phenyl-p-phenylenediamine, derivatives or mixtures thereof, etc. Is mentioned.
Further, as the vulcanizing agent, known vulcanizing agents such as sulfur, organic peroxides, resin vulcanizing agents and the like can be used. Examples of the vulcanization accelerator include known vulcanization accelerators such as aldehydes, ammonia, amines, guanidines, thioureas, thiazoles, sulfenamides, thiurams, dithiocarbamates, and xanthates. Can be used. Examples of the fatty acid include stearic acid, palmitic acid, myristic acid, lauric acid, and the like, and these may be blended in a salt state like zinc stearate. Of these, stearic acid is preferred. In addition, examples of the metal oxide include zinc white (ZnO), iron oxide, magnesium oxide, and the like. Among these, zinc white is preferable. The process oil may be aromatic, naphthenic, or paraffinic.

(Physical properties of resin material contained in tire frame)
Next, preferable physical properties of the resin material (material including the first component and ethylene propylene rubber) forming the tire frame will be described.

The melting point (or softening point) of the material (tire frame) itself is usually 100 ° C. to 350 ° C., preferably about 100 ° C. to 250 ° C., but about 120 ° C. to 250 ° C. from the viewpoint of tire productivity. Is preferable, and 120 to 200 ° C. is more preferable.
In this way, by using a resin material having a melting point of 120 ° C. to 250 ° C., for example, when a tire skeleton is formed by fusing the divided bodies (frame pieces), the periphery of 120 ° C. to 250 ° C. Even if the frame body is fused in the temperature range, the bonding strength between the tire frame pieces is sufficient. For this reason, the tire of this invention is excellent in durability at the time of driving | running | working, such as puncture resistance and abrasion resistance. The heating temperature is preferably 10 ° C to 150 ° C higher than the melting point (or softening point) of the resin material forming the tire frame piece, and more preferably 10 ° C to 100 ° C higher.

The resin material can be obtained by adding various additives as necessary and mixing them appropriately by a known method (for example, melt mixing).
The resin material obtained by melt mixing can be used in the form of pellets if necessary.

  The tensile yield strength specified in JIS K7113: 1995 of the resin material (tire frame) itself is preferably 5 MPa or more, preferably 5 MPa to 20 MPa, and more preferably 5 MPa to 17 MPa. When the tensile yield strength of the resin material is 5 MPa or more, the resin material can withstand deformation against a load applied to the tire during traveling.

  The tensile yield elongation defined by JIS K7113: 1995 of the material (tire frame) itself is preferably 10% or more, preferably 10% to 70%, and more preferably 15% to 60%. When the tensile yield elongation of the resin material is 10% or more, the elastic region is large, and the rim assembly property can be improved.

  The tensile elongation at break specified in JIS K7113: 1995 of the resin material (tire frame) itself is preferably 50% or more, preferably 100% or more, more preferably 150% or more, and particularly preferably 200% or more. When the tensile elongation at break of the resin material is 50% or more, the rim assembly property is good and it is possible to make it difficult to break against a collision.

  As a deflection temperature under load (at the time of 0.45 MPa load) specified in ISO 75-2 or ASTM D648 of the resin material (tire frame) itself, 50 ° C. or more is preferable, 50 ° C. to 150 ° C. is preferable, and 50 ° C. to 50 ° C. 130 ° C. is more preferable. When the deflection temperature under load of the resin material is 50 ° C. or higher, deformation of the tire skeleton can be suppressed even when vulcanization is performed in the manufacture of the tire.

  The tensile elastic modulus of the resin material (tire frame) itself is preferably 100 MPa to 500 MPa, more preferably 200 MPa to 400 MPa, and particularly preferably 200 MPa to 350 MPa from the viewpoints of rim assembly and internal pressure retention.

《Exterior material》
The tire of the present invention has an exterior member together with a tire skeleton. In the present invention, the “exterior member” means a member that is installed outside the tire frame body and covers at least a part of the outer surface of the tire frame body. The exterior member may be installed so as to be in direct contact with the surface of the tire frame body, or may be installed on an intervening layer or the like provided on the surface of the tire frame body. However, in the tire of the present invention, at least a part of the exterior member is in direct contact with the tire frame. Examples of the exterior member include a tread member installed at the crown portion of the tire frame body, a side member installed at the side portion of the tire frame body, and the like. The exterior member in the present invention is not necessarily the outermost layer of the tire of the present invention. For example, a decorative layer or a protective layer may be further provided on the outer surface of the exterior member.

  The exterior member includes ethylene propylene rubber. As an ethylene propylene rubber used for an exterior essential member, the same thing as the ethylene propylene rubber which can be used for the above-mentioned tire frame can be used. Moreover, as an ethylene propylene rubber used for the exterior member, EPDM or a modified product thereof is preferable from the viewpoint of easily increasing the strength by vulcanization.

For the exterior member, other elastomers or the like may be used in addition to the ethylene propylene rubber as long as the effects of the present invention are not impaired. Examples of the other elastomer include a diene rubber component.
Moreover, you may add another additive to the exterior member according to the objective. As said additive, well-known things, such as fillers, such as carbon black, and anti-aging agent, can be suitably selected according to the objective, for example.
The content of the ethylene propylene rubber in the exterior member is not particularly limited, and can be appropriately selected according to the use such as a tread member or a side member. However, from the viewpoint of sufficiently exhibiting the effects of the present invention, the content of the ethylene propylene rubber in the exterior member is preferably 65% by mass or more, and more preferably 70% by mass to 90% by mass. It is particularly preferably 75% by mass to 85% by mass. For example, as an exterior member, only an ethylene propylene rubber is used as a resin and an additive is added thereto, that is, an exterior member containing only the ethylene propylene rubber as a resin (other than an additive, other than an ethylene propylene rubber) The resin component and the rubber component are not included.

The exterior member can be formed by, for example, injection molding. For example, when forming a tread member, a belt-like tread member having a tread pattern composed of a plurality of grooves on a ground contact surface with a road surface can be formed by injection molding. In this case, one tread member is wound around the tire frame body, the temperature on the tread member side is set higher than the temperature on the tire frame body side using a hot runner or the like, and the tread member is formed on the crown portion surface of the tire frame body by heating. Can be welded. Thereby, the tire by which the tread part was welded to the crown part surface of a tire frame can be formed. In addition, after forming the tire frame body, the tire frame body is placed in a mold, and a composition containing EPDM, carbon black, or the like to be a tread member is injected into the mold, and then cooled, and the tire frame body is cooled. A tire having a tread portion welded to the crown portion surface may be formed. However, the manufacturing method of the tire of the present invention is not limited to these methods, and known methods can be used in appropriate combination.
Further, depending on the material and purpose, the exterior member may be vulcanized before or after the exterior member is installed on the tire frame body.

  The combination of the ethylene propylene rubber contained in the tire frame and the ethylene propylene rubber contained in the exterior member is not particularly limited, and the same ethylene propylene rubber may be used or different types of ethylene propylene. Rubber may be used. Specifically, the combination of ethylene propylene rubber contained in both members may be any combination of EPDM and EPDM, EPDM and EPM, EPM and EPM, and either one or Both may be modified products of ethylene propylene rubber.

  It is preferable that the tire frame body and the exterior member adhere to each other at the contact portion. Moreover, it is preferable that the exterior member itself is not too soft and not too hard from the viewpoint of sufficiently exhibiting the performance as a tread. Specifically, the tensile modulus of the exterior member is preferably 0.1 to 100 MPa, more preferably 0.1 to 50 MPa, and particularly preferably 0.1 to 5.0 MPa.

[First Embodiment]
A tire according to a first embodiment of the tire of the present invention will be described below with reference to the drawings.
The tire 10 of this embodiment will be described. FIG. 1A is a perspective view showing a partial cross section of the tire according to the first embodiment. FIG. 1B is a cross-sectional view of the bead portion attached to the rim. As shown in FIG. 1, the tire 10 of the present embodiment has a cross-sectional shape substantially similar to that of a conventional general rubber pneumatic tire.

  As shown in FIG. 1A, the tire 10 includes a pair of bead portions 12 that contact the bead seat 21 and the rim flange 22 of the rim 20 shown in FIG. A tire case 17 comprising: a side portion 14 extending in the direction of a tire; and a crown portion 16 (outer peripheral portion) for connecting a tire radial direction outer end of one side portion 14 and a tire radial direction outer end of the other side portion 14. ing.

  Here, the tire case 17 of the present embodiment uses, as a resin material, for example, a resin composition containing a polyolefin-based thermoplastic resin elastomer and EPDM in a ratio of 9: 1 including each additive. Can do.

  In the present embodiment, the tire case 17 is formed of a single resin material. However, the present invention is not limited to this configuration, and each part of the tire case 17 is similar to a conventional general rubber pneumatic tire. You may use the thermoplastic resin material which has a different characteristic for every (side part 14, crown part 16, bead part 12, etc.). Further, a reinforcing material (polymer material, metal fiber, cord, nonwoven fabric, woven fabric, etc.) is embedded in the tire case 17 (for example, the bead portion 12, the side portion 14, the crown portion 16 and the like), and the reinforcing material is provided. The tire case 17 may be reinforced.

  In the present invention, the tire frame body in the present invention is formed of a single resin material, but the tire frame body is configured by combining a plurality of materials for the crown part, the side part, etc. of the tire frame body in the present invention. You can also.

  At this time, the thickness of the crown portion of the tire skeleton can be appropriately selected in order to adjust the bending elastic modulus. However, in consideration of the tire weight and the like, 0.5 mm to 10 mm is preferable, and 1 mm to 5 mm is preferable. Further preferred is 1 mm to 4 mm. Similarly, the thickness of the side portion of the tire skeleton is more preferably 0.5 mm to 10 mm, and particularly preferably 1 mm to 5 mm. About the thickness of the crown part and side part of these tire frame bodies, it can be based on the average thickness of the test piece at the time of measuring the above-mentioned bending elastic modulus. In addition, you may measure the thickness of a tire frame body suitably using a well-known method and apparatus.

  The tire case 17 of the present embodiment is obtained by joining a pair of tire case halves (tire frame pieces) 17A formed of a resin material. The tire case half 17A is formed by injection molding or the like so that one bead portion 12, one side portion 14, and a half-width crown portion 16 are integrated with each other so as to face each other. It is formed by joining at the tire equator part. The tire case 17 is not limited to the one formed by joining two members, and may be formed by joining three or more members.

The tire case half 17A formed of the resin material can be formed by, for example, vacuum forming, pressure forming, injection molding, melt casting, or the like. For this reason, it is not necessary to perform vulcanization compared to the case where the tire case is molded with rubber as in the prior art, the manufacturing process can be greatly simplified, and the molding time can be omitted.
In the present embodiment, the tire case half body 17A has a symmetrical shape, that is, the one tire case half body 17A and the other tire case half body 17A have the same shape. There is also an advantage that only one type of mold is required.

  In the present embodiment, as shown in FIG. 1 (B), an annular bead core 18 made of a steel cord is embedded in the bead portion 12 as in a conventional general pneumatic tire. However, the present invention is not limited to this configuration, and the bead core 18 can be omitted if the rigidity of the bead portion 12 is ensured and there is no problem in fitting with the rim 20. In addition to the steel cord, an organic fiber cord, a resin-coated organic fiber cord, or a hard resin may be used.

  In the present embodiment, a material having a better sealing property than a resin material constituting the tire case 17 at a portion that contacts the rim 20 of the bead portion 12 or at least a portion that contacts the rim flange 22 of the rim 20, for example, rubber An annular seal layer 24 made of is formed. The seal layer 24 may also be formed at a portion where the tire case 17 (bead portion 12) and the bead sheet 21 are in contact with each other. As a material having better sealing properties than the resin material constituting the tire case 17, a softer material than the resin material constituting the tire case 17 can be used. As the rubber that can be used for the seal layer 24, it is preferable to use the same type of rubber as that used on the outer surface of the bead portion of a conventional general rubber pneumatic tire. Further, if the sealing property between the rim 20 can be ensured only by the resin material forming the tire case 17, the rubber seal layer 24 may be omitted, and other thermoplastic resins having a sealing property superior to the resin material. (Thermoplastic resin elastomer) may be used. Examples of such other thermoplastic resins include polyurethane resins, polyolefin resins, polystyrene thermoplastic resins, polyester resins, and the like, and blends of these resins with rubbers or elastomers. Also, a thermoplastic resin elastomer can be used, for example, a polyester-based thermoplastic resin elastomer, a polyurethane-based thermoplastic resin elastomer, a polystyrene-based thermoplastic resin elastomer, a polyolefin-based thermoplastic resin elastomer, or a combination of these elastomers, And blends with rubber.

  As shown in FIG. 1, a reinforcing cord 26 having higher rigidity than the resin material constituting the tire case 17 is wound around the crown portion 16 in the circumferential direction of the tire case 17. The reinforcing cord 26 is wound spirally in a state in which at least a part thereof is embedded in the crown portion 16 in a cross-sectional view along the axial direction of the tire case 17, thereby forming a reinforcing cord layer 28. A tread 30 made of a resin composition obtained by adding an additive such as carbon black to EPDM is disposed on the outer circumferential side of the reinforcing cord layer 28 in the tire radial direction.

  The reinforcing cord layer 28 formed by the reinforcing cord 26 will be described with reference to FIG. FIG. 2 is a cross-sectional view along the tire rotation axis showing a state where a reinforcing cord is embedded in the crown portion of the tire case of the tire of the first embodiment. As shown in FIG. 2, the reinforcing cord 26 is spirally wound in a state in which at least a part is embedded in the crown portion 16 in a sectional view along the axial direction of the tire case 17. A reinforcing cord layer 28 indicated by a broken line portion in FIG. 2 is formed together with a part of the outer peripheral portion 17. The portion embedded in the crown portion 16 of the reinforcing cord 26 is in close contact with the resin material constituting the crown portion 16 (tire case 17). As the reinforcing cord 26, a monofilament (single wire) such as a metal fiber or an organic fiber, or a multifilament (twisted wire) obtained by twisting these fibers such as a steel cord twisted with a steel fiber can be used. In the present embodiment, a steel cord is used as the reinforcing cord 26.

  In FIG. 2, the burying amount L indicates the burying amount of the reinforcing cord 26 in the tire rotation axis direction with respect to the tire case 17 (crown portion 16). The embedding amount L of the reinforcing cord 26 in the crown portion 16 is preferably 1/5 or more of the diameter D of the reinforcing cord 26, and more preferably more than 1/2. Most preferably, the entire reinforcing cord 26 is embedded in the crown portion 16. When the embedment amount L of the reinforcing cord 26 exceeds 1/2 of the diameter D of the reinforcing cord 26, it is difficult to jump out of the embedded portion due to the size of the reinforcing cord 26. Further, when the entire reinforcing cord 26 is embedded in the crown portion 16, the surface (outer peripheral surface) becomes flat, and even if a member is placed on the crown portion 16 where the reinforcing cord 26 is embedded, Air can be prevented from entering. The reinforcing cord layer 28 corresponds to a belt disposed on the outer peripheral surface of the carcass of a conventional rubber pneumatic tire.

A tread 30 is disposed on the outer circumferential side of the reinforcing cord layer 28 in the tire radial direction. EPDM is used for the tread 30. As shown in FIG. 2, in the present embodiment, the tread 30 is in direct contact with the crown portion 16 of the tire case 17. The tread 30 and the crown portion 16 are welded at the interface. The tread 30 is preferably superior in wear resistance to the resin material constituting the tire case 17. Further, the tread 30 is formed with a tread pattern including a plurality of grooves on the ground contact surface with the road surface in the same manner as a conventional rubber pneumatic tire.
Hereinafter, the manufacturing method of the tire of this embodiment is explained.

(Tire case molding process)
First, as described above, a tire case half is formed using a resin material containing a polyolefin-based thermoplastic resin elastomer and EPDM. These tire cases are preferably formed by injection molding. Next, the tire case halves supported by the thin metal support ring face each other. Next, a joining mold (not shown) is installed so as to be in contact with the outer peripheral surface of the abutting portion of the tire case half. Here, the said joining metal mold | die is comprised so that the periphery of the junction part (butting part) of the tire case half body 17A may be pressed with a predetermined pressure. Next, the periphery of the joint portion of the tire case half is pressed at a temperature equal to or higher than the melting point (or softening point) of the resin material constituting the tire case. When the joint portion of the tire case half is heated or pressed by the joining mold, the joint portion is melted and the tire case halves are fused together, and the tire case 17 is formed by integrating these members. In the present embodiment, the joining portion of the tire case half is heated using a joining mold, but the present invention is not limited to this. For example, the joining portion is heated by a separately provided high-frequency heater or the like. Or softened or melted beforehand by hot air, infrared irradiation, etc., and pressed by a joining mold. The tire case halves may be joined.

(Reinforcement cord member winding process)
Next, although not shown in the drawings, the heated reinforcing cord 26 is wound while being embedded in the outer peripheral surface of the crown portion 16 using a reel, a cord heating device, and a cord supply device provided with various rollers. Thus, the reinforcing cord layer 28 can be formed on the outer peripheral side of the crown portion 16 of the tire case 17.

(Exterior member installation process)
Next, the tread 30 is installed on the outer peripheral surface of the tire case 17. There is no particular limitation on the method of forming the tread 30 and the method of mounting on the tire case 17, but for example, the belt-shaped tread 30 having a tread pattern composed of a plurality of grooves is formed in advance on the ground contact surface with the road surface by injection molding, The tread 30 can be welded to the outer peripheral surface of the tire case 17 by winding the tread 30 around the tire case 17 and heating the tread 30 using a hot runner or the like. The tread 30 may be vulcanized after injection molding.

  And if the sealing layer 24 which consists of vulcanized rubber is adhere | attached on the bead part 12 of the tire case 17 using an adhesive agent etc., the tire 10 will be completed.

(Function)
In the tire 10 of the present embodiment, the tire case 17 is formed of a resin material including a polyolefin-based thermoplastic resin elastomer and EPDM, and the tread 30 is formed of EPDM. Therefore, no adhesive is used. Also, the tread 30 (exterior member) is difficult to peel off from the tire case 17. The tire 10 is light in weight because it has a simple structure as compared with a conventional rubber tire. For this reason, the tire 10 of this embodiment has high friction resistance and durability. Furthermore, since the tire case 17 and the tread 30 can be injection-molded, and the tread 30 is directly welded to the tire case 17, the step of applying an adhesive when the tread 30 is attached to the tire case 17 is omitted. be able to. For this reason, the tire 10 of this embodiment is very excellent in productivity.

  Further, in the tire 10 of the present embodiment, a reinforcing cord 26 having a rigidity higher than that of the resin material is spirally wound in the circumferential direction on the outer peripheral surface of the crown portion 16 of the tire case 17 formed of a resin material. Therefore, puncture resistance, cut resistance, and circumferential rigidity of the tire 10 are improved. In addition, creep of the tire case 17 formed of a resin material is prevented by improving the circumferential rigidity of the tire 10.

  In addition, at least a part of the reinforcing cord 26 is embedded in the outer peripheral surface of the crown portion 16 of the tire case 17 made of a resin material in a cross-sectional view along the axial direction of the tire case 17 (cross section shown in FIG. 1). In addition, since it is in close contact with the resin material, entry of air at the time of manufacture is suppressed, and movement of the reinforcing cord 26 due to input during travel is suppressed. Thereby, it is suppressed that peeling etc. arise in the reinforcement cord 26, the tire case 17, and the tread 30, and durability of the tire 10 improves.

  And since the embedding amount L of the reinforcement cord 26 is 1/5 or more of the diameter D as shown in FIG. 2, the air entry at the time of manufacture is suppressed effectively, the input at the time of driving, etc. This further suppresses the movement of the reinforcing cord 26.

  Further, since an annular bead core 18 made of a metal material is embedded in the bead portion 12, the tire case 17, that is, the tire 10 is strong against the rim 20 like the conventional rubber pneumatic tire. Retained.

  Furthermore, since a seal layer 24 made of a rubber material having a sealing property than the resin material constituting the tire case 17 is provided at a portion of the bead portion 12 that contacts the rim 20, the tire 10 and the rim 20 The sealing performance between the two is improved. For this reason, compared with the case where it seals only with the rim | limb 20 and the resin material which comprises the tire case 17, the air leak in a tire is suppressed further. Further, the rim fit property is improved by providing the seal layer 24.

  In the first embodiment, the reinforcing cord 26 is heated. However, for example, the outer periphery of the reinforcing cord 26 may be covered with the same resin material as the tire case 17. In this case, the covering reinforcing cord is used. When the wire is wound around the crown portion 16 of the tire case 17, the resin material covered with the reinforcing cord 26 is also heated, so that the air can be effectively suppressed when being embedded in the crown portion 16.

  Further, although it is easy to manufacture the reinforcing cord 26 in a spiral manner, a method of making the reinforcing cord 26 discontinuous in the width direction is also conceivable.

  The tire 10 of the first embodiment is a so-called tubeless tire in which an air chamber is formed between the tire 10 and the rim 20 by attaching the bead portion 12 to the rim 20, but the present invention is limited to this configuration. It may be a complete tube shape.

[Second Embodiment]
Next, a tire according to a second embodiment of the tire of the present invention will be described with reference to the drawings.
The tire 200 of this embodiment will be described. FIG. 3 is a perspective view showing a cross section of a part of the tire according to the second embodiment. As shown in FIG. 3, the tire 200 of the present embodiment is provided with a side member 15 as an exterior member on the outer side in the width direction of both side portions 14 with respect to the tire 10 of the first embodiment. In FIG. 3, members that are the same as those in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted.

  In the tire 200 of this embodiment, in addition to the tread 30 formed using EPDM, a side member 15 is mounted on the surface of the side portion 14 as an exterior member. The side member 15 is formed using the same material as the tread 30, that is, a resin composition in which an additive such as carbon black is added to EPDM. As with the tread 30, the side member 15 is preferably superior in wear resistance to the resin material constituting the tire case 17. The side member 15 is in direct contact with the surface of the side portion 14 and is welded at the interface.

The side member 15 can be formed by injection molding or the like, similarly to the tread 30. Further, the side member 15 may be vulcanized after injection molding.
As shown in FIG. 3, in the present embodiment, the end portion of the side member 15 on the crown portion 16 side is bonded so as to overlap the end portion of the tread 30. At this time, it is preferable that the end portion of the side member 15 on the crown portion 16 side is installed so as to be located on the inner side in the tire radial direction than the end portion of the tread 30. Further, the tread 30 and the side member 15 can be configured to be welded at the interface between the overlapping end portions.

  In the present embodiment, in order to attach the side member 15 and the tread 30 to the tire case 17, first, the side member 15 is welded to the side portion 14 of the tire case 17. The method for attaching the side member 15 is not particularly limited. For example, the side member 15 formed by injection molding is heated on the outer surface of the side portion 14 by heating the side member 15 using a hot runner or the like. Can be welded. Next, the tread 30 is wound around the outer peripheral surface of the tire case 17 by winding the tread 30 on the belt-shaped tread 30 tire case 17 so that the end overlaps the end of the side member 15 and heating the tread 30 using a hot runner or the like. Can do.

  In addition, in this embodiment, although the aspect in which the side member 15 was installed in the both sides of the side part 14 of the tire case 17 was shown, the tire of this invention is not limited to this embodiment, The tire width of the tire 200 The side member 15 may be provided only on one side in the direction.

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various modifications can be made without departing from the scope of the invention. It goes without saying that the scope of rights of the present invention is not limited to these embodiments.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to this.

  First, tires of examples and comparative examples having the structure shown in the first embodiment were formed. Under the present circumstances, the material of the following Tables 1-3 was used about the material which forms a tire case and the member for exterior (tread). In addition, except when the adhesive layer is provided (in this case, the tire frame body and the exterior member are not in direct contact with each other), the tire case and the tread are heated at the temperatures shown in the table (welding temperature). Welded.

Abbreviations in the table mean the following. In the table, the numerical value indicating each component means “part by mass”.
-Polypropylene A: acid-modified polyolefin-based thermoplastic resin elastomer, manufactured by Mitsui Chemicals (product name Toughmer QE060)
Polypropylene B: Polyolefin thermoplastic elastomer, manufactured by Prime Polymer Co., Ltd. (product name: Prime TPO “J-5710”)
・ Diene rubber A: Butadiene rubber, manufactured by JSR Corporation (product name: BR01)
・ Rubber B: Natural rubber ・ Elastomer A: Mitsui Chemicals Co., Ltd. (Product name: Miralastomer “7030NS”)
・ Polyethylene A: Ube Maruzen Polyethylene Co., Ltd. (Product name: Umerit “1540F”)
-EPDM: manufactured by Mitsui Chemicals (product name: EPT X-3012P)
Acid-modified EPDM: Product made by Addant Japan (Product name: ROYALTUF “498”)
EPM: manufactured by Mitsui Chemicals (product name: EPT 0045)
・ Carbon black: Asahi Carbon Co., Ltd. (Product name: # 80)

[Tensile shear test]
Using the material used to form the tire skeleton used in each Example and Comparative Example and the material used for the tread, and used for the plate-shaped test piece and the tread created using the material forming the skeleton by injection molding. A test piece was prepared in which the material to be bonded was bonded in an area of half inch (25 mm × 12.5 mm). Next, a tensile shear test was performed using a tensile test device (device name: universal tester Autograph AG-X, manufactured by Shimadzu Corporation) under the conditions of a tensile speed of 100 mm / min, a chuck interval of 20 mm, and 23 ° C. Three sample pieces were prepared for each example and comparative example, and evaluation was performed according to the following criteria based on the results. If this evaluation is “C” or more, the tire has acceptable performance.
<Standard>
A: The material of all three sample pieces was destroyed, and the welding power of both members was good.
B: Only one or two sample pieces were destroyed, but the welding power of both members was sufficient.
C: Although the sample piece was peeled at the interface between the members, a force (peeling energy) was required for peeling.
D: The sample piece was easily peeled at the interface between the members without requiring force (peeling energy) during peeling.

[Tensile modulus]
Using pellets having the same composition as the tire case (tire frame body) and tread (exterior member) produced in the examples and comparative examples, injection molding is performed using SE30D manufactured by Sumitomo Heavy Industries, and a molding temperature of 180 ° C. A sample having a size of 100 mm × 30 mm and a thickness of 2.0 mm was obtained for the tire frame body and the exterior member corresponding to each of the examples and comparative examples, with a mold temperature of −260 ° C. and a mold temperature of 50 ° C. to 70 ° C. In addition, about the tire frame body of Example 29 and the member for exterior of the comparative example 2, the sample piece was produced by press molding.
Each sample was punched out to produce a dumbbell-shaped sample piece (No. 5 type sample piece) defined in JISK6251: 1993.

  Subsequently, using the Shimadzu Corporation make and Shimadzu autograph AGS-J (5KN), the tension | pulling speed was set to 200 mm / min, and the tensile elasticity modulus in 80 degreeC of each said dumbbell-shaped sample piece was measured. The results are shown in Tables 1-3.

10,200 tires, 12 bead portions, 14 side portions, 15 side members, 16 crown portions (outer peripheral portions), 18 bead cores, 20 rims, 21 bead seats, 22 rim flanges, 17 tire cases (tire frame bodies), 24 seals Layer (seal part), 26 Reinforcement cord (reinforcement cord member), 28 Reinforcement cord layer, 30 tread, D Reinforcement cord diameter (reinforcement cord member diameter), L Reinforcement cord embedding amount (reinforcement cord member embedding amount)

Claims (4)

An annular tire skeleton formed of a material including at least one selected from diene rubbers and polyolefin thermoplastic elastomers; and ethylene propylene rubber;
An exterior member that is in direct contact with at least a portion of the tire skeleton and includes ethylene propylene rubber;
Including tires. The tire according to claim 1 , wherein the polyolefin-based thermoplastic resin elastomer is a copolymer of polypropylene and polyethylene. The tire according to claim 1 or 2 , wherein the exterior member includes only the ethylene propylene rubber. The content of the ethylene propylene rubber in the tire frame body is 10 to 30 with respect to at least one total amount of 100 parts by mass selected from the diene rubber and the polyolefin thermoplastic resin elastomer in the tire frame body. tire according to any one of claims 1 to 3 parts by mass.