JP5813416B2 - tire - Google Patents

Description

  The present invention relates to a tire mounted on a rim, and particularly relates to a tire formed at least partially from a thermoplastic material.

  Conventionally, pneumatic tires made of rubber, organic fiber materials, steel members, and the like are used in vehicles such as passenger cars.

In recent years, from the viewpoint of weight reduction, ease of molding, and ease of recycling, the use of resin materials, particularly thermoplastic resins and thermoplastic elastomers, as tire materials has been studied.
For example, Patent Document 1 discloses a pneumatic tire formed using a thermoplastic polymer material.

JP 2003-104008 A

A tire using a thermoplastic polymer material is easier to manufacture and lower in cost than a conventional rubber tire. However, when the tire frame is formed of a uniform thermoplastic polymer material that does not have a reinforcing member such as a carcass ply, it is improved in terms of stress resistance and internal pressure resistance compared to conventional rubber tires. There is room.
Further, when a tire is manufactured using a thermoplastic polymer material, it is required to realize performance comparable to that of a conventional rubber tire while increasing manufacturing efficiency and realizing low cost.

  The present invention has been made in view of the above circumstances, and is formed using a thermoplastic resin material, and an increase in rolling resistance is suppressed even when the elastic modulus increases, and a tire excellent in durability is provided. The purpose is to do.

(1) The tire of the present invention is a tire having an annular tire skeleton formed of a thermoplastic resin material, wherein the thermoplastic resin material has a hard segment and a soft segment containing a polyester resin. Plastic elastomer (A) (hereinafter appropriately referred to as “polyester-based thermoplastic elastomer (A)”) and polyester resin (B) other than thermoplastic elastomer (hereinafter appropriately referred to as “polyester resin (B)”). )).

  Here, in this specification, the “thermoplastic elastomer” is a thermoplastic resin material having a hard segment and a soft segment in a molecule, and more specifically, is a polymer compound having elasticity, which is crystalline. A thermoplastic resin material comprising a copolymer having a hard segment having a high melting point and a non-crystalline polymer having a low glass transition temperature.

  In the present invention, the “polyester-based thermoplastic elastomer” is a polymer compound having elasticity, comprising a crystalline polymer having a high melting point hard segment and an amorphous soft glass segment having a low glass transition temperature. It is a thermoplastic resin material comprising a copolymer having a constituent polymer, and includes a polyester resin as a polymer constituting a hard segment. The “polyester resin” refers to a resin having an ester bond in the main chain.

  In the present specification, “resin” means a resin having thermoplasticity or thermosetting property, and does not include conventional vulcanized rubber such as natural rubber and synthetic rubber. Thermoplastic elastomers also do not include vulcanized rubber such as conventional natural rubber or synthetic rubber.

  The polyester resin (B) in the present invention is preferably the same type of resin as the polyester resin contained in the hard segment in the polyester thermoplastic elastomer (A). Here, “the same type of resin as the polyester resin contained in the hard segment” refers to a polyester resin having a skeleton that is the same as the skeleton constituting the main chain of the hard segment of the polyester thermoplastic elastomer.

Since the polyester resin (B) is a polyester resin having a skeleton that is the same as the skeleton constituting the main chain of the hard segment of the polyester thermoplastic elastomer (A), the hard segment in the polyester thermoplastic elastomer (A) It is thought that the affinity between the polyester resin (B) and the polyester resin (B) increases. In this case, since the thermoplastic resin material contains the polyester thermoplastic elastomer (A) and the polyester resin (B), the polyester resin (B) is compatible with the hard segment of the polyester thermoplastic elastomer (A). However, it is unevenly distributed in the hard segment of the polyester-based thermoplastic elastomer (A), and the area of the hard segment becomes large.
Therefore, the thermoplastic resin material containing the polyester-based thermoplastic elastomer (A) and the polyester resin (B) simply includes the polyester-based thermoplastic elastomer (A) and the polyester resin (B), and the polyester resin (B) Rather than being uniformly dispersed in the polyester-based thermoplastic elastomer (A) and having the respective properties, the region of the hard segment of the polyester-based thermoplastic elastomer (A) is increased, and the thermoplastic resin material Increases elastic modulus.

By the way, the rolling resistance of the tire is caused by vibrations around 10 Hz to 100 Hz around 50 ° C. Therefore, when the viscoelasticity of the tire is measured, the rolling resistance can be expressed by tan δ of 30 ° C. to 50 ° C. .
A tire formed using a resin material composed only of a polyester thermoplastic elastomer (A) has a loss tangent (tan δ) when the elastic modulus is increased by increasing the number of hard segment regions of the thermoplastic elastomer. Tend to be larger. Specifically, when the elastic modulus is increased by changing the ratio of the hard segment and the soft segment of the polyester thermoplastic elastomer (A), the peak of tan δ of the polyester thermoplastic elastomer (A) in the viscoelasticity measurement is high. And tan δ at 30 ° C. to 50 ° C. tends to increase.
When the loss tangent (tan δ) of the resin material increases, the energy loss (heat generation) generated by the deformation when the tire rolls increases, and the rolling resistance tends to increase. Therefore, an automobile using a tire made of such a resin material as a raw material tends to have high fuel efficiency.
That is, in a tire formed using a resin material composed only of a thermoplastic elastomer, when the elastic modulus of the resin material is increased for the purpose of improving the deformation resistance of the tire, the tan δ of the resin material is increased at the same time. Therefore, it was difficult to achieve low fuel consumption.

On the other hand, the elastic modulus of the thermoplastic resin material is increased by forming a tire by using a thermoplastic resin material containing a polyester-based thermoplastic elastomer (A) and a polyester resin (B) and forming a tire. However, tan δ is difficult to increase. The increase in tan δ is significantly suppressed when the polyester resin (B) is the same type of resin as the polyester resin contained in the hard segment in the polyester-based thermoplastic elastomer (A). The reason for such an effect is not clear, but is presumed to be as follows.
When the ratio of the hard segment and the soft segment of the polyester-based thermoplastic elastomer (A) is changed to increase the elastic modulus, the tan δ peak of the polyester-based thermoplastic elastomer (A) shifts to the high temperature side, and 30 Increase tan δ of ˜50 ° C.
On the other hand, when the polyester resin (B) is compatible with the hard segment region of the polyester-based thermoplastic elastomer (A), the hard segment region becomes large, and the shift of the tan δ peak to the high temperature side is suppressed. In this case, the tan δ peak of the polyester resin (B) appears, but tan δ as a whole of the thermoplastic resin material is suppressed.
From the above, in the present invention, even if the elastic modulus of the thermoplastic resin material is increased, tan δ is unlikely to increase.

Furthermore, the polyester-based thermoplastic elastomer has an advantage that it has heat resistance, impact resistance and oil resistance, and is excellent in tensile elastic modulus, tensile strength and breaking strain. Further, the polyester-based thermoplastic elastomer also has an advantage that the change in the elastic modulus due to the temperature change is small as compared with other thermoplastic elastomers.
For this reason, the polyester thermoplastic elastomer (A) is used in combination with the polyester resin (B), and while exhibiting excellent properties derived from the polyester thermoplastic elastomer, it also exhibits an effect of suppressing rolling resistance. It is possible to obtain a tire with good durability and low fuel consumption.

(2) The tire of the present invention can be configured such that the elastic modulus of the polyester resin (B) is 700 MPa or more.
Thus, by making the elastic modulus of the polyester resin (B) easily compatible with the hard segment of the polyester-based thermoplastic elastomer (A) within the above range, the hard segment of the polyester-based thermoplastic elastomer (A) Since the elastic modulus can be further increased, a thermoplastic resin material having a higher elastic modulus can be obtained. As a result, a tire having a higher elastic modulus can be obtained.

(3) The tire of the present invention is configured such that a mass ratio (A: B) of the polyester-based thermoplastic elastomer (A) and the polyester resin (B) is 95: 5 to 50:50. be able to.
When the mass ratio of the polyester-based thermoplastic elastomer (A) and the polyester resin (B) is in the above range, the performance of the thermoplastic resin material can be sufficiently exerted, and the tensile properties such as tensile elasticity and breaking strength as tire performance. Can be improved.

(4) The tire of this invention can be comprised so that content of the said polyester-type thermoplastic elastomer (A) in the said thermoplastic resin material may be 50 mass%-95 mass%.
When the content of the polyester-based thermoplastic elastomer (A) in the thermoplastic resin material is within the above range, the performance of the thermoplastic resin material can be sufficiently exerted, and tensile properties such as tensile elasticity and breaking strength as tire performance Can be further improved.

(5) Further, in the tire of the present invention, in addition to the tire skeleton formed of the thermoplastic resin material, a reinforcing cord member is wound around the outer periphery of the tire skeleton formed of the thermoplastic resin material. You may have the reinforcement cord member which forms a reinforcement cord layer.
When a reinforcing cord member is wound around the outer periphery of a tire skeleton formed of a thermoplastic resin material to form a reinforcing cord layer, the tire has a puncture resistance, a cut resistance, and a tire (tire skeleton). The circumferential rigidity of the is improved. In addition, the improvement of the circumferential rigidity suppresses the creep of the tire frame formed of a thermoplastic material (a phenomenon in which the plastic deformation of the tire frame increases with time under a certain stress).

  As described above, according to the present invention, it is possible to provide a tire that is formed using a thermoplastic resin material, that suppresses an increase in rolling resistance even when the elastic modulus increases, and that has excellent durability. .

(A) is a perspective view showing a section of a part of a tire concerning one embodiment of the present invention, and (B) is a sectional view of a bead part attached to a rim. 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 explanatory drawing for demonstrating the operation | movement which embeds a reinforcement cord in the crown part of a tire case using a cord heating apparatus and rollers. (A) is sectional drawing along the tire width direction of the tire which concerns on one Embodiment of this invention. (B) is an enlarged view of a cross section along a tire width direction of a bead portion in a state where a rim is fitted to a tire. It is sectional drawing along the tire width direction which shows the circumference | surroundings of the reinforcement layer of the tire of 2nd Embodiment. It is the graph which plotted the relationship between the tensile elasticity modulus of each sample piece of the Example and comparative example which were created with the thermoplastic resin material, and tan-delta.

  First, the thermoplastic resin material constituting the tire skeleton in the present invention will be described, and then specific embodiments of the tire of the present invention will be described with reference to the drawings.

[Thermoplastic resin material]
The tire of the present invention is a tire having an annular tire skeleton formed of a thermoplastic resin material, and the thermoplastic resin material has a polyester-based thermoplastic elastomer (a hard segment containing a polyester resin and a soft segment) A) and a tire including a polyester resin (B) other than a thermoplastic elastomer.

Rolling of tires by applying a combination of a polyester-based thermoplastic elastomer (A) and a polyester resin (B) other than a thermoplastic elastomer as a thermoplastic resin material constituting an annular tire skeleton forming a tire. It is possible to make the tire difficult to increase the resistance and excellent in durability.
Hereinafter, the polyester-based thermoplastic elastomer (A) and the polyester resin (B) other than the thermoplastic elastomer will be described.

[Polyester thermoplastic elastomer (A)]
The polyester-based thermoplastic elastomer (A) in the present invention is a polymer compound having elasticity, and is composed of a crystalline polymer having a high melting point and a non-crystalline soft segment having a low glass transition temperature. It is a thermoplastic resin material made of a copolymer having a polymer, and includes a polyester resin as a polymer constituting the hard segment. Examples of the polyester-based thermoplastic elastomer include ester-based thermoplastic elastomer (TPC) defined in JIS K6418: 2007.

  The polyester-based thermoplastic elastomer (A) is not particularly limited, but the crystalline polyester constitutes a hard segment having a high melting point, and the amorphous polymer constitutes a soft segment having a low glass transition temperature. The copolymer which is mentioned.

An aromatic polyester can be used as the crystalline polyester that forms the hard segment. The aromatic polyester can be formed, for example, from an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol.
Examples of the aromatic polyester that forms the hard segment include polyethylene terephthalate, polybutylene terephthalate, polystyrene terephthalate, polyethylene naphthalate, and polybutylene naphthalate. Polybutylene terephthalate is preferable.

  One suitable aromatic polyester that forms the hard segment includes terephthalic acid and / or polybutylene terephthalate derived from dimethyl terephthalate and 1,4-butanediol, and further includes isophthalic acid, phthalic acid, naphthalene. Dicarboxylic acids such as -2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, diphenyl-4,4'-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sulfoisophthalic acid, or ester-forming derivatives thereof Ingredients and diols having a molecular weight of 300 or less [for example, aliphatic diols such as ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, decamethylene glycol, 1,4-cyclohexane dimeta , Cycloaliphatic diols such as tricyclodecane dimethylol, xylylene glycol, bis (p-hydroxy) diphenyl, bis (p-hydroxyphenyl) propane, 2,2-bis [4- (2-hydroxyethoxy) Phenyl] propane, bis [4- (2-hydroxy) phenyl] sulfone, 1,1-bis [4- (2-hydroxyethoxy) phenyl] cyclohexane, 4,4′-dihydroxy-p-terphenyl, 4,4 It may be a polyester derived from an aromatic diol such as' -dihydroxy-p-quarterphenyl], or a copolymer polyester in which two or more of these dicarboxylic acid components and diol components are used in combination. It is also possible to copolymerize a trifunctional or higher polyfunctional carboxylic acid component, polyfunctional oxyacid component, polyfunctional hydroxy component, and the like in a range of 5 mol% or less.

Examples of the polymer forming the soft segment include polymers selected from aliphatic polyesters and aliphatic polyethers.
Aliphatic polyethers include poly (ethylene oxide) glycol, poly (propylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol, copolymers of ethylene oxide and propylene oxide, poly (propylene oxide) Examples thereof include ethylene oxide addition polymers of glycol and copolymers of ethylene oxide and tetrahydrofuran.
Examples of the aliphatic polyester include poly (ε-caprolactone), polyenantlactone, polycaprylolactone, polybutylene adipate, and polyethylene adipate.

  Among these aliphatic polyethers and aliphatic polyesters, poly (tetramethylene oxide) glycol, poly (propylene oxide) glycol ethylene oxide adduct, poly (ε-caprolactone) from the viewpoint of the elastic properties of the resulting copolymer Polybutylene adipate, polyethylene adipate and the like are preferable.

  The number average molecular weight of the polymer (polyester) forming the hard segment is preferably 300 to 6000 from the viewpoint of toughness and low temperature flexibility. Moreover, as a number average molecular weight of the polymer which forms a soft segment, 300-6000 are preferable from a viewpoint of toughness and low temperature flexibility. Furthermore, the volume ratio (x: y) to the hard segment (x) and the soft segment (y) is preferably 99: 1 to 20:80, more preferably 98: 2 to 30:70, from the viewpoint of moldability. .

  The polyester-based thermoplastic elastomer (A) can be synthesized by copolymerizing the polymer forming the hard segment and the polymer forming the soft segment by a known method.

  As the polyester-based thermoplastic elastomer (A), commercially available products can also be used. For example, “Hytrel” series (for example, 3046, 5557, 6347, 4047, 4767, 7247, etc.) manufactured by Toray DuPont, “Perprene” series (for example, P30B, P40B, P40H, P55B, P70B, P150B, P250B, E450B, P150M, S1001, S2001, S5001, S6001, S9001, etc.) manufactured by Toyobo Co., Ltd. can be used.

  The polyester-based thermoplastic elastomer (A) contained in the thermoplastic resin material may be two or more types, but from the viewpoint of controlling the tire performance of the tire formed using the thermoplastic resin material, the polyester-based thermoplastic elastomer The elastomer (A) is preferably one type.

[Polyester resin (B)]
The thermoplastic resin material includes a polyester resin (B) other than the thermoplastic elastomer. The polyester resin is a resin having an ester bond in the main chain.

  Although it does not specifically limit as a polyester resin (B), It is preferable that it is the same kind of resin as the polyester resin which the hard segment in a polyester-type thermoplastic elastomer (A) contains, and it is crystalline polyester. More preferred.

As the crystalline polyester, an aromatic polyester can be used. The aromatic polyester can be formed, for example, from an aromatic dicarboxylic acid or an ester-forming derivative thereof and an aliphatic diol.
Examples of the aromatic polyester include polyethylene terephthalate, polybutylene terephthalate, polystyrene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and the like, and polybutylene terephthalate is preferable.

  One of the aromatic polyesters includes terephthalic acid and / or polybutylene terephthalate derived from dimethyl terephthalate and 1,4-butanediol, and further, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid A dicarboxylic acid component such as naphthalene-2,7-dicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sulfoisophthalic acid, or an ester-forming derivative thereof, and a molecular weight of 300 or less Diol [for example, aliphatic diol such as ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, decamethylene glycol, 1,4-cyclohexanedimethanol, tricyclodecane dimethylo Alicyclic diols such as ruthenium, xylylene glycol, bis (p-hydroxy) diphenyl, bis (p-hydroxyphenyl) propane, 2,2-bis [4- (2-hydroxyethoxy) phenyl] propane, bis [4 -(2-hydroxy) phenyl] sulfone, 1,1-bis [4- (2-hydroxyethoxy) phenyl] cyclohexane, 4,4'-dihydroxy-p-terphenyl, 4,4'-dihydroxy-p-quarter It may be a polyester derived from an aromatic diol such as phenyl] or a copolyester in which two or more of these dicarboxylic acid components and diol components are used in combination. It is also possible to copolymerize a trifunctional or higher polyfunctional carboxylic acid component, polyfunctional oxyacid component, polyfunctional hydroxy component, and the like in a range of 5 mol% or less.

  Commercially available products may be used as the polyester resin as described above. For example, “Duranex” series (for example, 2000, 2002, etc.) manufactured by Polyplastics Co., Ltd., Novaduran manufactured by Mitsubishi Engineering Plastics Co., Ltd. Series (for example, 5010R5, 5010R3-2, etc.), “Toraycon” series (for example, 1401X06, 1401X31, etc.) manufactured by Toray Industries, Inc. can be mentioned.

In addition, the polyester resin (B) is from the viewpoint of increasing the elastic modulus of the thermoplastic resin material.
The elastic modulus is preferably 700 MPa or more, and more preferably 800 MPa to 3000 MPa. The elastic modulus of the polyester resin (B) means the tensile elastic modulus specified in JIS K7113: 1995, and the elastic modulus of the specific resin is, for example, a precision universal testing machine autograph manufactured by Shimadzu Corporation. Can be measured.

  The thermoplastic resin material may contain two or more kinds of polyester resins (B). However, it is preferable that at least one of them needs to be the same type of polyester resin as the hard segment of the polyester-based thermoplastic elastomer (A). Further, as described above, since the polyester-based thermoplastic elastomer (A) in the thermoplastic resin material is preferably one type, the polyester resin (B) is also preferably one type.

In the thermoplastic resin material, the mass ratio (A: B) of the polyester-based thermoplastic elastomer (A) and the polyester resin (B) is 95: 5 to 50:50 on a mass basis from the viewpoint of impact resistance. It is preferably 90:10 to 50:50, and more preferably 90:10 to 50:50.
Further, in the thermoplastic resin material, the content of the polyester-based thermoplastic elastomer (A) is 95% by mass to 50% by mass with respect to the total mass of the thermoplastic resin material from the viewpoint of impact resistance. Preferably, it is 90 mass%-10 mass%.

  As long as the effects of the present invention are not impaired, other thermoplastic elastomers, various fillers (for example, silica, calcium carbonate, clay), anti-aging agents, oils, plasticizers may be used as the thermoplastic resin material. Various additives such as a colorant, a weathering agent, and a reinforcing material may be contained.

  The thermoplastic resin material can be obtained by mixing the polyester-based thermoplastic elastomer (A) and the polyester resin (B), adding various additives as necessary, and melt-mixing them. The mixing ratio of the polyester-based thermoplastic elastomer (A) and the polyester resin (B) is in accordance with the ratio described above. The thermoplastic resin material obtained by melt mixing can be used in the form of pellets if necessary.

  As the tensile elastic modulus (hereinafter referred to as “elastic modulus” in the present specification unless otherwise specified) as defined in JIS K7113: 1995 of the thermoplastic resin material, 100 MPa to 1000 MPa is preferable. 100 MPa to 800 MPa is more preferable, and 100 MPa to 700 MPa is particularly preferable. When the tensile modulus of the thermoplastic resin material is 100 MPa to 1000 MPa, the rim can be assembled efficiently while maintaining the shape of the tire frame.

  The tensile yield strength specified in JIS K7113: 1995 of the thermoplastic resin material 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 thermoplastic resin material is 5 MPa or more, the thermoplastic resin material can withstand deformation against a load applied to the tire during traveling.

  The tensile yield elongation specified in JIS K7113: 1995 of the thermoplastic resin material is preferably 10% or more, preferably 10 to 70%, and more preferably 15 to 60%. When the tensile yield elongation of the polyester-based thermoplastic elastomer is 10% or more, the elastic region is large and the rim assembly property can be improved.

  The tensile fracture elongation specified in JIS K7113: 1995 of the thermoplastic resin material is preferably 50% or more, preferably 100% or more, more preferably 150% or more, and particularly preferably 200% or more. When the tensile fracture elongation of the thermoplastic 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 ISO75-2 or ASTM D648 of the thermoplastic resin material, 50 ° C. or more is preferable, 50 to 150 ° C. is preferable, and 50 to 130 ° C. is more preferable. When the deflection temperature under load of the thermoplastic resin material is 50 ° C. or higher, deformation of the tire frame body can be suppressed even when vulcanization is performed in the manufacture of the tire.

[Resin material constituting the reinforcing cord layer]
The tire of the present invention may have a reinforcing cord member that is wound in the circumferential direction on the outer peripheral portion of the tire frame to form a reinforcing cord layer.
Further, the reinforcing cord layer can be configured to include a resin material. In this way, when the resin material is included in the reinforcing cord layer, the difference in hardness between the tire and the reinforcing cord layer can be reduced as compared with the case where the reinforcing cord member is fixed with cushion rubber. The cord member can be adhered and fixed to the tire frame. The “resin material” is a concept including a thermoplastic resin (including a thermoplastic elastomer) and a thermosetting resin, and does not include vulcanized rubber.

  Examples of the thermosetting resin that can be used for the reinforcing cord layer include phenol resin, urea resin, melamine resin, epoxy resin, polyamide resin, and polyester resin.

  Examples of the thermoplastic resin include urethane resin, olefin resin, vinyl chloride resin, polyamide resin, and polyester resin.

Examples of the thermoplastic elastomer include amide-based thermoplastic elastomer (TPA), ester-based thermoplastic elastomer (TPC), olefin-based thermoplastic elastomer (TPO), and styrene-based thermoplastic elastomer (specified in JIS K6418: 2007). TPS), urethane-based thermoplastic elastomer (TPU), crosslinked thermoplastic rubber (TPV), or other thermoplastic elastomer (TPZ). Note that it is preferable to use a thermoplastic elastomer in consideration of elasticity required at the time of traveling, moldability at the time of manufacture, and the like.
Moreover, the same kind of resin material refers to forms, such as ester systems and styrene systems.

  The elastic modulus (tensile elastic modulus specified in JIS K7113: 1995) of the resin material used for the reinforcing cord layer is in the range of 0.1 to 10 times the elastic modulus of the thermoplastic resin forming the tire frame body. It is preferable to set. When the elastic modulus of the resin material is 10 times or less than the elastic modulus of the thermoplastic resin material forming the tire frame body, the crown portion is not too hard and rim assembly is facilitated. Further, when the elastic modulus of the resin material is 0.1 times or more of the elastic modulus of the thermoplastic resin material forming the tire frame body, the resin constituting the reinforcing cord layer is not too soft and the in-plane shear rigidity Excellent cornering power.

[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 a tire according to an embodiment of the present invention. 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 (tire frame) comprising: a side portion 14 extending in the direction of a tire; and a crown portion 16 (outer peripheral portion) that connects a tire radial direction outer end of one side portion 14 and a tire radial direction outer end of the other side portion 14. Body) 17.

  Here, the tire case 17 of the present embodiment is made of a polyester-based thermoplastic elastomer (“Hytrel 3046” manufactured by Toray DuPont Co., Ltd.) and a polyester resin (“Juranex 2000” manufactured by Polyplastics Co., Ltd.). It is made of a mixed material. In the present embodiment, the tire case 17 is formed of a single thermoplastic resin material. However, the present invention is not limited to this configuration, and the tire case 17 is similar to a conventional rubber pneumatic tire. You may use the thermoplastic resin material which has a different characteristic for every site | part (the side part 14, the crown part 16, the 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.

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 thermoplastic 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 thermoplastic resin material contains a polyester-based thermoplastic elastomer (A) and a polyester resin (B).
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 a thermoplastic resin material can be molded by, for example, vacuum molding, pressure molding, 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 thermoplastic 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, An annular seal layer 24 made of rubber 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 a better sealing property than the thermoplastic resin material constituting the tire case 17, a softer material can be used as compared with the thermoplastic resin material constituting the tire case 17. 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. Moreover, if the sealing property between the rim 20 can be ensured only with the thermoplastic resin material, the rubber seal layer 24 may be omitted, and a thermoplastic resin (including a thermoplastic elastomer) having an excellent sealing property is used. Also good. Examples of such thermoplastic resins include polyurethane resins, olefin resins, polystyrene resins, polyamide resins, polyester resins, and the like, and blends of these resins with rubbers or elastomers. In addition, as the thermoplastic elastomer, a thermoplastic elastomer such as a polyurethane thermoplastic elastomer, a polyamide thermoplastic elastomer, a polyester thermoplastic elastomer, a polyolefin thermoplastic elastomer, a polystyrene thermoplastic elastomer, or a combination of these elastomers. And a blend with rubber.

  As shown in FIG. 1, a reinforcing cord 26 having higher rigidity than the thermoplastic 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 material having higher wear resistance than the thermoplastic resin material constituting the tire case 17, for example, rubber, 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 the reinforcing cord 26 is embedded in the crown portion of the tire case of the tire according to 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 thermoplastic 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.

  As described above, the tread 30 is disposed on the outer peripheral side of the reinforcing cord layer 28 in the tire radial direction. The rubber used for the tread 30 is preferably the same type of rubber as that used in conventional rubber pneumatic tires. Instead of the tread 30, a tread formed of another type of thermoplastic resin material that is more excellent in wear resistance than the thermoplastic resin material constituting the tire case 17 may be used. 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 tire manufacturing method of the present invention will be described.
(Tire case molding process)
First, tire case halves supported by a 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 A 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 of the thermoplastic resin material constituting the tire case. When the joining portion of the tire case half is heated and pressurized by the joining mold, the joining 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, the reinforcing cord winding process will be described with reference to FIG. FIG. 3 is an explanatory diagram for explaining an operation of embedding a reinforcing cord in a crown portion of a tire case using a cord heating device and rollers. In FIG. 3, the cord supply device 56 includes a reel 58 around which the reinforcing cord 26 is wound, a cord heating device 59 arranged on the downstream side of the reel 58 in the code conveyance direction, and a first code arranged on the downstream side of the cord 26 in the conveyance direction. 1 roller 60, a first cylinder device 62 that moves the first roller 60 in a direction of moving toward and away from the outer peripheral surface of the tire, and a downstream side in the conveying direction of the reinforcing cord 26 of the first roller 60. A second roller 64, and a second cylinder device 66 that moves the second roller 64 in a direction in which the second roller 64 comes in contact with and separates from the tire outer peripheral surface. The second roller 64 can be used as a metal cooling roller. Further, in the present embodiment, the surface of the first roller 60 or the second roller 64 is made of a fluororesin (in this embodiment, Teflon (registered trademark)) in order to suppress adhesion of a molten or softened thermoplastic resin material. ). In the present embodiment, the cord supply device 56 is configured to have two rollers, the first roller 60 or the second roller 64, but the present invention is not limited to this configuration, and any one of the rollers. It is also possible to have only one (that is, one roller).

  The cord heating device 59 includes a heater 70 and a fan 72 that generate hot air. Further, the cord heating device 59 includes a heating box 74 through which the cord 26 passes through an internal space in which hot air is supplied, and a discharge port 76 for discharging the heated cord 26.

  In this step, first, the temperature of the heater 70 of the cord heating device 59 is raised, and the ambient air heated by the heater 70 is sent to the heating box 74 by the wind generated by the rotation of the fan 72. Next, the reinforcing cord 26 unwound from the reel 58 is fed into a heating box 74 in which the internal space is heated with hot air (for example, the temperature of the reinforcing cord 26 is heated to about 100 to 200 ° C.). The heated reinforcing cord 26 passes through the discharge port 76 and is wound spirally around the outer peripheral surface of the crown portion 16 of the tire case 17 rotating in the direction of arrow R in FIG. Here, when the heated reinforcing cord 26 comes into contact with the outer peripheral surface of the crown portion 16, the thermoplastic resin material in the contact portion is melted or softened, and at least a part of the heated reinforcing cord 26 is outer peripheral surface of the crown portion 16. Buried in At this time, since the heated reinforcing cord 26 is embedded in the molten or softened thermoplastic elastomer, the thermoplastic resin material and the reinforcing cord 26 are in a state where there is no gap, that is, in a close contact state. Thereby, the air entering to the portion where the reinforcing cord 26 is embedded is suppressed. In addition, by heating the reinforcing cord 26 to a temperature higher than the melting point of the thermoplastic resin material of the tire case 17, melting or softening of the thermoplastic elastomer in the portion in contact with the reinforcing cord 26 is promoted. By doing in this way, it becomes easy to embed the reinforcement cord 26 in the outer peripheral surface of the crown part 16, and air entry can be effectively suppressed.

  The embedment amount L of the reinforcing cord 26 can be adjusted by the heating temperature of the reinforcing cord 26, the tension applied to the reinforcing cord 26, the pressing force by the first roller 60, and the like. In the present embodiment, the embedding amount L of the reinforcing cord 26 is set to be 1/5 or more of the diameter D of the reinforcing cord 26. The burying amount L of the reinforcing cord 26 is more preferably more than 1/2 of the diameter D, and most preferably the entire reinforcing cord 26 is embedded.

  In this way, the reinforcing cord layer 28 is formed on the outer peripheral side of the crown portion 16 of the tire case 17 by winding the heated reinforcing cord 26 while being embedded in the outer peripheral surface of the crown portion 16.

  Next, a vulcanized belt-like tread 30 is wound around the outer peripheral surface of the tire case 17 for one turn, and the tread 30 is bonded to the outer peripheral surface of the tire case 17 using an adhesive or the like. In addition, the precure tread used for the retread tire conventionally known can be used for the tread 30, for example. This step is the same step as the step of bonding the precure tread to the outer peripheral surface of the base tire of the retreaded tire.

  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, since the tire case 17 is formed of a thermoplastic resin material that is a mixed material of the polyester-based thermoplastic elastomer (A) and the polyester resin (B), the elasticity of the thermoplastic resin material. Even if the rate is increased, the tan δ of the thermoplastic resin material is hardly increased, and the rolling resistance of the tire can be suppressed. Furthermore, since the structure of the tire 10 of the present embodiment can be simplified by using a thermoplastic resin material, the weight is lighter than rubber used in conventional tires. For this reason, if the tire 10 of this embodiment is applied to a motor vehicle, it can reduce in weight and can suppress a fuel consumption.

  Further, the polyester-based thermoplastic elastomer contained in the thermoplastic resin material has adhesion to the reinforcing cord 26. For this reason, the phenomenon (air entering) in which air remains around the reinforcing cord 26 in the reinforcing cord winding step can be suppressed. If there is adhesion to the reinforcement cord 26 and the entry of air into the periphery of the reinforcement cord member is suppressed, it is possible to effectively suppress the movement of the reinforcement cord 26 due to input during traveling or the like. Thereby, for example, even when the tire constituent member is provided so as to cover the entire reinforcing cord member on the outer peripheral portion of the tire frame body, the movement of the reinforcing cord member is suppressed. The peeling of the tire frame (including the tire frame) is suppressed, and the durability of the tire 10 is improved.

  In the tire 10 of the present embodiment, the reinforcing cord 26 having higher rigidity than the thermoplastic 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 the thermoplastic resin material. Therefore, puncture resistance, cut resistance, and circumferential rigidity of the tire 10 are improved. In addition, the creep of the tire case 17 formed of the thermoplastic 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 formed on the outer peripheral surface of the crown portion 16 of the tire case 17 made of a thermoplastic resin material in a cross-sectional view along the axial direction of the tire case 17 (the cross section shown in FIG. 1). Since it is embedded and is in close contact with the thermoplastic 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.
In this way, when the reinforcing cord layer 28 is made of a thermoplastic resin material containing a polyester-based thermoplastic elastomer, the tire case 17 and the reinforcing cord layer 28 are compared with the case where the reinforcing cord 26 is fixed with cushion rubber. Therefore, the reinforcing cord 26 can be further adhered and fixed to the tire case 17. Thereby, the above-mentioned air entering can be prevented effectively, and it can control effectively that a reinforcement cord member moves at the time of driving.
Further, when the reinforcing cord 26 is a steel cord, the reinforcing cord 26 can be easily separated and recovered from the thermoplastic resin material by heating at the time of disposal of the tire, which is advantageous in terms of recyclability of the tire 10. .
In addition, since the polyester-based thermoplastic elastomer has a lower loss coefficient (Tan δ) than vulcanized rubber, the rolling property of the tire can be improved.
Furthermore, the polyester-based thermoplastic elastomer has an advantage that the in-plane shear rigidity is larger than that of the vulcanized rubber, and the stability and wear resistance during running of the tire are excellent.

In addition, since the tread 30 that is in contact with the road surface is made of a rubber material that is more wear resistant than the thermoplastic resin material, the wear resistance of the tire 10 is improved.
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 rather than a thermoplastic resin material is provided in a portion that contacts the rim 20 of the bead portion 12, a seal between the tire 10 and the rim 20 is provided. Improves. For this reason, the air leak in a tire is further suppressed compared with the case where it seals with the rim | limb 20 and a thermoplastic resin material. Further, the rim fit property is improved by providing the seal layer 24.

  In the first embodiment, the reinforcing cord 26 is heated, and the thermoplastic resin material in a portion where the heated reinforcing cord 26 contacts is melted or softened. However, the present invention is not limited to this configuration, and the reinforcing cord is used. It is also possible to use a hot air generating device without heating 26 and heat the outer peripheral surface of the crown portion 16 in which the reinforcing cord 26 is embedded, and then embed the reinforcing cord 26 in the crown portion 16.

  In the first embodiment, the heat source of the cord heating device 59 is a heater and a fan. However, the present invention is not limited to this configuration, and the reinforcement cord 26 is directly heated by radiant heat (for example, infrared rays). Also good.

  Further, in the first embodiment, the portion in which the thermoplastic resin material in which the reinforcing cord 26 is embedded is melted or softened is forcibly cooled by the metal second roller 64, but the present invention is configured in this manner. However, the present invention may be configured to forcibly cool and solidify the melted or softened portion of the thermoplastic resin material by directly blowing cold air to the melted or softened portion of the thermoplastic resin material.

  In the first embodiment, the reinforcement cord 26 is heated. However, for example, the outer periphery of the reinforcement cord 26 may be covered with the same thermoplastic resin material as the tire case 17. When the covering reinforcing cord is wound around the crown portion 16 of the tire case 17, the thermoplastic resin material covered with the reinforcing cord 26 is also heated, thereby effectively suppressing air entry when embedded in the crown portion 16. it can.

  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 has this configuration. It is not limited and a perfect tube shape may be sufficient.

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 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 the present invention is not limited to these embodiments.

[Second Embodiment]
Next, a tire manufacturing method and a second embodiment of the tire according to the present invention will be described with reference to the drawings. Similar to the first embodiment, the tire according to the present embodiment has substantially the same cross-sectional shape as that of a conventional general rubber pneumatic tire. For this reason, in the following figures, the same number is attached | subjected about the structure similar to the said 1st Embodiment. FIG. 4A is a cross-sectional view along the tire width direction of the tire of the second embodiment, and FIG. 4B is a bead portion in a state where a rim is fitted to the tire of the second embodiment. It is an enlarged view of a section along the tire width direction. FIG. 5 is a cross-sectional view along the tire width direction showing the periphery of the reinforcing layer of the tire of the second embodiment.

  In the tire according to the second embodiment, the tire case 17 is made of a thermoplastic resin material (polyester-based thermoplastic elastomer (“Hytrel 3046” manufactured by Toray DuPont Co., Ltd.)) and polyester, as in the first embodiment. It is made of a resin (mixed material with “Duranex 2000” manufactured by Polyplastics Co., Ltd.). In the present embodiment, as shown in FIGS. 4 and 5, the tire 200 includes a reinforcing cord layer 28 (indicated by a broken line in FIG. 11) formed by winding a covering cord member 26 </ b> B around the crown portion 16 in the circumferential direction. Are stacked). The reinforcing cord layer 28 constitutes the outer peripheral portion of the tire case 17 and reinforces the circumferential rigidity of the crown portion 16. The outer peripheral surface of the reinforcing cord layer 28 is included in the outer peripheral surface 17S of the tire case 17.

  The covering cord member 26B is formed by coating a covering resin material 27 that is separate from the thermoplastic resin material forming the tire case 17 on the cord member 26A having higher rigidity than the thermoplastic resin material forming the tire case 17. Is formed. Further, the covering cord member 26B is joined (for example, welded or adhered with an adhesive) at the contact portion with the crown portion 16 where the covering cord member 26B and the crown portion 16 are joined.

  The elastic modulus of the resin material 27 for covering is preferably set in the range of 0.1 to 10 times the elastic modulus of the resin material forming the tire case 17. When the elastic modulus of the coating resin material 27 is 10 times or less than the elastic modulus of the thermoplastic resin material forming the tire case 17, the crown portion does not become too hard and rim assembly is facilitated. When the elastic modulus of the coating resin material 27 is 0.1 times or more of the elastic modulus of the thermoplastic resin material forming the tire case 17, the resin constituting the reinforcing cord layer 28 is not too soft and the belt surface Excellent internal shear rigidity and improved cornering force. In this embodiment, as the resin material 27 for covering, the same type of material as the thermoplastic resin material constituting the tire case 17 (“Hytrel 3046” manufactured by Toray DuPont) and polyester resin (polyplastic) And a mixed material with “Juranex 2000” manufactured by Susu Co., Ltd.).

  Further, as shown in FIG. 5, the coated cord member 26B has a substantially trapezoidal cross-sectional shape. In the following description, the upper surface (the surface on the outer side in the tire radial direction) of the covering cord member 26B is denoted by reference numeral 26U, and the lower surface (the surface on the inner side in the tire radial direction) is denoted by reference numeral 26D. In the present embodiment, the cross-sectional shape of the covering cord member 26B is a substantially trapezoidal shape. However, the present invention is not limited to this configuration, and the cross-sectional shape is from the lower surface 26D side (the tire radial direction inner side) to the upper surface 26U. Any shape may be used as long as the shape excluding the shape that becomes wider toward the side (the tire radial direction outer side).

  As shown in FIG. 5, since the covering cord members 26B are arranged at intervals in the circumferential direction, a gap 28A is formed between the adjacent covering cord members 26B. For this reason, the outer peripheral surface of the reinforcing cord layer 28 is uneven, and the outer peripheral surface 17S of the tire case 17 in which the reinforcing cord layer 28 forms the outer peripheral portion is also uneven.

  On the outer peripheral surface 17S (including irregularities) of the tire case 17, fine roughened irregularities 96 are uniformly formed, and a cushion rubber 29 is bonded thereon via a bonding agent. In the cushion rubber 29, the radially inner rubber portion flows into the roughened unevenness 96.

  In addition, a tread 30 made of a material having higher wear resistance than the resin material forming the tire case 17, for example, rubber, is joined on the cushion rubber 29 (outer peripheral surface).

  The rubber used for the tread 30 (tread rubber 30A) is preferably the same type of rubber as that used for conventional rubber pneumatic tires. Instead of the tread 30, a tread formed of another type of resin material that is more excellent in wear resistance than the resin material forming the tire case 17 may be used. Further, the tread 30 is formed with a tread pattern (not shown) including a plurality of grooves on the ground contact surface with the road surface, similarly to the conventional rubber pneumatic tire.

Next, the manufacturing method of the tire of this embodiment is demonstrated.
(Skeleton formation process)
(1) First, the tire case half body 17A is formed in the same manner as in the first embodiment described above, and this is heated and pressed by a joining mold to form the tire case 17.

(Reinforcement cord member winding process)
(2) The tire manufacturing apparatus in the present embodiment is the same as that in the first embodiment described above. In the cord supply apparatus 56 shown in FIG. 3 of the first embodiment described above, the cord member 26A is attached to the reel 58. A material obtained by winding a covering cord member 26B having a substantially trapezoidal cross-sectional shape, which is covered with a covering resin material 27 (a thermoplastic material in this embodiment), is used.

  First, the temperature of the heater 70 is raised, and the ambient air heated by the heater 70 is sent to the heating box 74 by the wind generated by the rotation of the fan 72. The coated cord member 26B unwound from the reel 58 is fed into the heating box 74 in which the internal space is heated with hot air (for example, the temperature of the outer peripheral surface of the coated cord member 26B is equal to or higher than the melting point of the coating resin material 27). And Here, when the covering cord member 26B is heated, the covering resin material 27 is melted or softened.

  The covering cord member 26B is spirally wound around the outer peripheral surface of the crown portion 16 of the tire case 17 that rotates in the front direction of the paper through the discharge port 76 with a certain tension. At this time, the lower surface 26 </ b> D of the covering cord member 26 </ b> B contacts the outer peripheral surface of the crown portion 16. Then, the molten or softened covering resin material 27 in the contacted portion spreads on the outer peripheral surface of the crown portion 16, and the covering cord member 26 </ b> B is welded to the outer peripheral surface of the crown portion 16. Thereby, the joint strength between the crown portion 16 and the covering cord member 26B is improved.

(Roughening process)
(3) Next, with a blasting device not shown, the projection material is injected onto the outer peripheral surface 17S at a high speed while rotating the tire case 17 side (arrow R direction) toward the outer peripheral surface 17S of the tire case 17. To do. The ejected projection material collides with the outer peripheral surface 17S, and fine roughening unevenness 96 having an arithmetic average roughness Ra of 0.05 mm or more is formed on the outer peripheral surface 17S.
Thus, by forming the fine roughening unevenness 96 on the outer peripheral surface 17S of the tire case 17, the outer peripheral surface 17S becomes hydrophilic, and the wettability of the bonding agent described later is improved.

(Lamination process)
(4) Next, a bonding agent is applied to the outer peripheral surface 17S of the tire case 17 subjected to the roughening treatment. The bonding agent is not particularly limited, such as triazine thiol adhesive, chlorinated rubber adhesive, phenolic resin adhesive, isocyanate adhesive, halogenated rubber adhesive, etc., but cushion rubber 29 is vulcanized. It is preferable to react at a temperature (90 ° C. to 140 ° C.) that can be performed.

(5) Next, the unvulcanized cushion rubber 29 is wound around the outer peripheral surface 17S to which the bonding agent has been applied for one round, and a bonding agent such as a rubber cement composition is applied on the cushion rubber 29, for example. Then, a vulcanized or semi-vulcanized tread rubber 30A is wound for one turn to obtain a raw tire case state.

(Vulcanization process)
(6) Next, the raw tire case is accommodated in a vulcanizing can or mold and vulcanized. At this time, the unvulcanized cushion rubber 29 flows into the roughened irregularities 96 formed on the outer peripheral surface 17S of the tire case 17 by the roughening treatment. When the vulcanization is completed, the anchor rubber is exerted by the cushion rubber 29 flowing into the roughened unevenness 96, and the bonding strength between the tire case 17 and the cushion rubber 29 is improved. That is, the bonding strength between the tire case 17 and the tread 30 is improved via the cushion rubber 29.
In the vulcanization process, it is necessary to increase the temperature to a temperature (90 ° C. to 140 ° C.) at which the cushion rubber 29 can be vulcanized, and when only a thermoplastic resin other than the polyester-based thermoplastic elastomer is used for the tire case, The temperature rise at the time of vulcanization may cause the tire case 17 to bend and thus affect the tire formation maintenance. In this respect, the polyester-based thermoplastic elastomer has a higher deflection temperature under load than other thermoplastic elastomers, so that the tire shape maintainability can be further improved and the tire productivity can also be improved. .

(7) When the seal layer 24 made of a soft material softer than the resin material is bonded to the bead portion 12 of the tire case 17 using an adhesive or the like, the tire 200 is completed.

(8) Finally, the diameter of the tire support portion 40 is reduced, the completed tire 200 is removed from the tire support portion 40, the internal tire inner surface support ring 43 is bent and deformed, and is removed from the tire.

(Function)
In the tire 200 of the present embodiment, since the tire case 17 is formed of a thermoplastic resin material that is a mixed material of the polyester-based thermoplastic elastomer (A) and the polyester resin (B), the elasticity of the thermoplastic resin material. Even if the rate is increased, the tan δ of the thermoplastic resin material is hardly increased, and the rolling resistance of the tire can be suppressed. Further, the tire 200 of the present embodiment can be simplified in structure by using a thermoplastic resin material, so that the weight is lighter than rubber used in conventional tires. For this reason, the tire 200 of this embodiment can be reduced in weight, and the vehicle provided with this has good fuel consumption.

Further, the polyester-based thermoplastic elastomer used as one of the thermoplastic resin materials has adhesiveness to the covering cord member 26 </ b> B constituting the reinforcing cord layer 28.
When the reinforcing cord layer 28 is configured to include the covering cord member 26B as described above, the hardness of the tire case 17 and the reinforcing cord layer 28 compared to the case where the cord member 26A is simply fixed by the cushion rubber 29. Therefore, the coated cord member 26 </ b> B can be further adhered and fixed to the tire case 17. Thereby, air entry can be effectively prevented, and the reinforcement cord member can be effectively suppressed from moving during traveling.
Further, when the cord member 26A is a steel cord in particular, the cord member 26A can be easily separated and collected from the coated cord member 26B by heating at the time of disposal of the tire, which is advantageous in terms of recyclability of the tire 200. is there. In addition, since the polyester-based thermoplastic elastomer has a lower loss coefficient (Tan δ) than vulcanized rubber, the rolling property of the tire can be improved. Furthermore, the polyester-based thermoplastic elastomer has an advantage that the in-plane shear rigidity is larger than that of the vulcanized rubber, and the stability and wear resistance during running of the tire are excellent.

  In the tire manufacturing method of the present embodiment, since the outer peripheral surface 17S of the tire case 17 is roughened when the tire case 17, the cushion rubber 29, and the tread rubber 30A are integrated, the bondability is achieved by the anchor effect. (Adhesiveness) is improved. Further, since the resin material forming the tire case 17 is dug up by the collision of the projection material, the wettability of the bonding agent is improved. Thereby, the bonding agent is held in a uniform applied state on the outer peripheral surface 17S of the tire case 17, and the bonding strength between the tire case 17 and the cushion rubber 29 can be ensured.

  In particular, even when the outer circumferential surface 17S of the tire case 17 is configured with the unevenness 96, a roughening process is performed around the recess (concave wall, bottom) by causing the projection material to collide with the recess (gap 28A). It is possible to secure the bonding strength between the cushion 17 and the cushion rubber 29.

  On the other hand, since the cushion rubber 29 is laminated in the roughened region of the outer peripheral surface 17S of the tire case 17, the bonding strength between the tire case 17 and the cushion rubber can be effectively ensured.

  In the vulcanization step, when the cushion rubber 29 is vulcanized, the cushion rubber 29 flows into the roughened irregularities 96 formed on the outer peripheral surface 17S of the tire case 17 by the roughening process. When the vulcanization is completed, the anchor rubber is exerted by the cushion rubber 29 flowing into the roughened unevenness 96, and the bonding strength between the tire case 17 and the cushion rubber 29 is improved.

  The tire 200 manufactured by such a tire manufacturing method ensures the bonding strength between the tire case 17 and the cushion rubber 29, that is, the bonding between the tire case 17 and the tread 30 via the cushion rubber 29. Strength is secured. Thereby, the peeling between the outer peripheral surface 17S of the tire case 17 of the tire 200 and the cushion rubber 29 is suppressed during traveling or the like.

  Further, since the outer peripheral portion of the tire case 17 is configured by the reinforcing cord layer 28, the puncture resistance and the cut resistance are improved as compared with the outer peripheral portion configured by other than the reinforcing cord layer 28. To do.

  Further, since the reinforcing cord layer 28 is formed by winding the covering cord member 26B, the circumferential rigidity of the tire 200 is improved. By improving the circumferential rigidity, creep of the tire case 17 (a phenomenon in which plastic deformation of the tire case 17 increases with time under a constant stress) is suppressed, and pressure resistance against air pressure from the inner side in the tire radial direction is suppressed. improves.

In 2nd Embodiment, although the unevenness | corrugation was comprised in the outer peripheral surface 17S of the tire case 17, this invention is not restricted to this, It is good also as a structure which forms the outer peripheral surface 17S flatly.
In addition, the tire case 17 may be formed with a reinforcing cord layer so as to cover the covering cord member wound and joined to the crown portion of the tire case with a covering thermoplastic material. In this case, the coating thermoplastic material can be ejected onto the reinforcing cord layer 28 in the molten or softened state to form the coating layer. Further, without using an extruder, the welding sheet may be heated to be in a molten or softened state and attached to the surface (outer peripheral surface) of the reinforcing cord layer 28 to form a coating layer.

  In 2nd Embodiment, it was set as the structure which joins a case division body (tire case half body 17A) and forms the tire case 17, However, This invention is not restricted to this structure, The tire case 17 using a metal mold | die etc. May be formed integrally.

  The tire 200 of the second embodiment is a so-called tubeless tire in which an air chamber is formed between the tire 200 and the rim 20 by attaching the bead portion 12 to the rim 20, but the present invention has this configuration. Without being limited, the tire 200 may be, for example, a complete tube shape.

  In the second embodiment, the cushion rubber 29 is disposed between the tire case 17 and the tread 30. However, the present invention is not limited to this, and the cushion rubber 29 may not be disposed.

  In the second embodiment described above, the covering cord member 26B is spirally wound around the crown portion 16, but the present invention is not limited thereto, and the covering cord member 26B is discontinuous in the width direction. It is good also as a structure wound so that it may become.

In the second embodiment, the coating resin material 27 forming the coating cord member 26B is made of a thermoplastic material, and the coating resin material 27 is heated to be melted or softened so that the outer peripheral surface of the crown portion 16 is coated. Although the cord member 26B is welded, the present invention is not limited to this configuration, and the covering cord member 26B is bonded to the outer peripheral surface of the crown portion 16 using an adhesive or the like without heating the coating resin material 27. It is good also as composition to do.
The covering resin material 27 for forming the covering cord member 26B may be a thermosetting resin, and the covering cord member 26B may be bonded to the outer peripheral surface of the crown portion 16 using an adhesive or the like without being heated.
Further, the covering resin material 27 for forming the covering cord member 26B may be a thermosetting resin, and the tire case 17 may be formed of a thermoplastic material. In this case, the covering cord member 26B may be bonded to the outer peripheral surface of the crown portion 16 using an adhesive or the like, and the portion of the tire case 17 where the covering cord member 26B is disposed is heated to be melted or softened. The covering cord member 26 </ b> B may be welded to the outer peripheral surface of the crown portion 16 in a state.
Still further, the covering resin material 27 for forming the covering cord member 26B may be made of a thermoplastic material, and the tire case 17 may be made of a thermoplastic material.
In this case, the covering cord member 26B may be bonded to the outer peripheral surface of the crown portion 16 using an adhesive or the like, and the portion of the tire case 17 where the covering cord member 26B is disposed is heated to be melted or softened. The coating resin material 27 may be heated to a molten or softened state while the coating cord member 26 </ b> B is welded to the outer peripheral surface of the crown portion 16. In addition, when both the tire case 17 and the covering cord member 26B are heated and melted or softened, the two are mixed well, so that the bonding strength is improved. When both the resin material forming the tire case 17 and the covering resin material 27 forming the covering cord member 26B are thermoplastic materials, the same kind of thermoplastic material, particularly the same thermoplastic material, should be used. Is preferred.

  Furthermore, the outer peripheral surface 17S of the tire case 17 subjected to the roughening treatment may be subjected to corona treatment, plasma treatment or the like to activate the surface of the outer peripheral surface 17S to increase hydrophilicity, and then apply an adhesive. Good.

Furthermore, the order for manufacturing the tire 200 is not limited to the order of the second embodiment, and may be changed as appropriate.
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 the present invention is not limited to these embodiments.

  As mentioned above, although the specific aspect of this invention was demonstrated using 1st Embodiment and 2nd Embodiment, this invention is not limited to the above-mentioned aspect.

As shown in the first embodiment, the tire of the present invention can be configured as follows.
(1-1) In the tire according to the present invention, at least a part of the reinforcing cord member is embedded in the outer peripheral portion of the tire frame formed of a thermoplastic resin material in a cross-sectional view along the axial direction of the tire frame. It can be constituted as follows.
As described above, when a part of the reinforcing cord member is embedded in the outer peripheral portion of the tire frame body, it is possible to further suppress a phenomenon (air entering) in which air remains around the cord when the reinforcing cord member is wound. When the entry of air into the periphery of the reinforcement cord member is suppressed, the movement of the reinforcement cord member due to input during traveling is suppressed. Thereby, for example, when the tire constituent member is provided on the outer peripheral portion of the tire skeleton body so as to cover the entire reinforcement cord member, the movement of the reinforcement cord member is suppressed. ) Is prevented from being peeled off and the durability is improved.

(1-2) The tire of the present invention may be provided with a tread formed of a material having more wear resistance than the thermoplastic resin material on the radially outer side of the reinforcing cord layer.
Thus, the abrasion resistance of the tire can be further improved by configuring the tread that contacts the road surface with a material that is more resistant to abrasion than the thermoplastic resin material.

(1-3) In the tire according to the present invention, in a cross-sectional view along the axial direction of the tire frame body, a diameter 1/5 or more of the reinforcing cord member is embedded in the outer peripheral portion of the tire frame body along the circumferential direction. Can be made.
Thus, when 1/5 or more of the diameter of the reinforcing cord member is embedded in the outer peripheral portion of the tire frame body in a cross-sectional view along the axial direction of the tire frame body, it is effective to enter the air around the reinforcing cord member It is possible to suppress the movement of the reinforcing cord member due to an input during traveling.

(1-4) In the tire according to the present invention, the tire frame has a bead portion in contact with a rim bead sheet and a rim flange on a radially inner side, and an annular bead core made of a metal material is embedded in the bead portion. Can be configured.
Thus, by providing a bead portion that is a fitting portion with the rim in the tire frame body, and further by embedding an annular bead core made of a metal material in this bead portion, it is the same as a conventional rubber pneumatic tire. In addition, the tire frame (that is, the tire) can be firmly held against the rim.

(1-5) In the tire of the present invention, a seal portion made of a material having a higher sealing property (adhesion with the rim) than the thermoplastic resin material can be provided at a portion where the bead portion contacts the rim.
Thus, by providing a seal portion made of a material having a higher sealing property than the thermoplastic resin material at the contact portion between the tire frame body and the rim, adhesion between the tire (tire frame body) and the rim can be improved. Can be improved. Thereby, compared with the case where only a rim | limb and a thermoplastic resin material are used, the air leak in a tire can be suppressed further. Moreover, the rim fit property of a tire can also be improved by providing the said seal part.

(1-6) The tire of this invention forms the tire frame piece which comprises a part of cyclic | annular tire frame body with the thermoplastic resin material containing a polyester-type thermoplastic elastomer (A) and a polyester resin (B) at least. A tire skeleton piece forming step, a tire skeleton piece joining step in which the tire skeleton body is formed by fusing two or more paired tire skeleton pieces by applying heat to the joint surfaces of the tire skeleton pieces; and the tire The reinforcing cord member is wound around the outer peripheral portion of the skeleton body in the circumferential direction to form a reinforcing cord layer, and can be manufactured by a manufacturing method including a reinforcing cord member winding step.

(1-7) The tire manufacturing method is configured so that, in the tire frame piece bonding step, a bonding surface of the tire frame piece is heated to a temperature equal to or higher than a melting point of the thermoplastic resin material forming the tire frame piece. Can do.
As described above, when the joining surface of the divided body is heated to a temperature equal to or higher than the melting point of the thermoplastic resin material constituting the tire frame piece, the tire frame pieces can be sufficiently fused with each other. The productivity of the tire can be increased while improving.

(1-8) In the tire manufacturing method, in the reinforcing cord member winding step, at least one of the reinforcing cord members while melting or softening an outer peripheral portion of the tire frame body formed in the tire frame piece joining step. The reinforcing cord member can be wound around the outer peripheral portion of the tire frame body by burying the portion.
In this way, at least a part of the reinforcing cord member was embedded while melting or softening the outer peripheral portion of the tire frame body, and the reinforcing cord member was wound around the outer peripheral portion of the tire frame body. At least a part of the reinforcing cord member can be welded to the molten or softened thermoplastic resin material. Thereby, the air entering between the outer peripheral part of the tire frame and the reinforcing cord member can be further suppressed in a cross-sectional view along the axial direction of the tire frame. Moreover, when the portion in which the reinforcing cord member is embedded is cooled and solidified, the fixing degree of the reinforcing cord member embedded in the tire frame body is improved.

(1-9) In the tire manufacturing method, in the reinforcing cord member winding step, 1/5 or more of the diameter of the reinforcing cord in the tire cord body in a cross-sectional view along the axial direction of the tire frame body. It can be configured to be embedded in the outer periphery.
As described above, when the reinforcing cord member is embedded in the outer peripheral portion of the tire frame body by 1/5 or more of the diameter in a cross-sectional view along the axial direction of the tire frame body, it is effective for air to enter the periphery of the reinforcement cord at the time of manufacture. In addition, the embedded reinforcing cord member can be made difficult to come off from the tire frame body.

(1-10) The tire manufacturing method may be configured to embed the heated reinforcing cord member in the tire frame body in the reinforcing cord member winding step.
Thus, in the reinforcing cord winding step, when the reinforcing cord member is embedded in the tire frame body while heating, the contact portion melts or softens when the heated reinforcing cord member contacts the outer periphery of the tire frame body. Therefore, the reinforcing cord member can be easily embedded in the outer peripheral portion of the tire frame body.

(1-11) The tire manufacturing method may be configured to heat a portion of the outer periphery of the tire frame body where the reinforcing cord member is embedded in the cord member winding step.
Thus, by heating the portion where the reinforcement cord member is embedded in the outer peripheral portion of the tire frame body, the heated portion of the tire frame body is melted or softened, so that the reinforcement cord member is easily embedded.

(1-12) In the manufacturing method of the tire, in the cord member winding step, the reinforcing cord is pressed in a circumferential direction of the outer peripheral portion of the tire frame body while pressing the reinforcing cord member against the outer peripheral portion of the tire frame body. The member can be configured to be spirally wound.
As described above, when the reinforcing cord member is spirally wound while pressing the reinforcing cord member against the outer peripheral portion of the tire frame body, the amount of the reinforcing cord member embedded in the outer peripheral portion of the tire frame body can be adjusted. it can.

(1-13) According to the tire manufacturing method, in the cord member winding step, after the reinforcing cord member is wound around the tire frame body, a melted or softened portion of the outer periphery of the tire frame body Can be configured to cool.
In this way, after the reinforcing cord member is embedded, the melted or softened portion of the outer periphery of the tire frame body is forcibly cooled to naturally cool the melted or softened portion of the outer periphery of the tire frame body. Faster and faster cooling and solidification. By cooling the tire outer peripheral portion faster than natural cooling, it is possible to suppress deformation of the outer peripheral portion of the tire frame body and to suppress movement of the reinforcing cord member.

In addition, as described in the second embodiment, the tire of the present invention can be configured as follows.
(2-1) In the tire manufacturing method according to the present invention, the tire is further roughened by causing the particulate projection material to collide with the outer peripheral surface of the tire frame to roughen the outer peripheral surface of the tire frame. A processing step and a laminating step of laminating a tire constituting rubber member via a bonding agent on the roughened outer peripheral surface can be provided.
As described above, when the roughening treatment step is provided, the outer peripheral surface of the annular tire skeleton formed by using the thermoplastic resin material including the polyester-based thermoplastic elastomer (A) and the polyester resin (B) is particulate. The projection material collides, and fine roughening irregularities are formed on the outer peripheral surface. In addition, the process which makes a projection material collide with the outer peripheral surface of a tire frame body and forms fine roughening unevenness | corrugation is called roughening process. Thereafter, a tire constituting rubber member is laminated on the outer peripheral surface subjected to the roughening treatment via a bonding agent. Here, since the outer peripheral surface of the tire frame is roughened when integrating the tire frame and the tire constituent rubber member, the bondability (adhesiveness) is improved by the anchor effect. In addition, since the resin material forming the tire frame is dug up by the collision of the projection material, the wettability of the outer peripheral surface is improved. Thereby, the bonding agent is held in a uniform applied state on the outer peripheral surface of the tire frame body, and the bonding strength between the tire frame body and the tire constituting rubber member can be ensured.

(2-2) In the tire of the present invention, at least a part of the outer peripheral surface of the tire frame body is an uneven portion, and the uneven portion can be prepared by performing a roughening treatment in the roughening treatment step.
As described above, even when at least a part of the outer peripheral surface of the tire skeleton is an uneven portion, the projection material is collided with the uneven portion to roughen the periphery of the recessed portion (concave wall, concave bottom), and the tire Bonding strength between the skeleton body and the tire constituting rubber member can be ensured.

(2-3) In the tire according to the present invention, the outer peripheral portion of the tire frame body is formed of a reinforcing layer that forms the uneven portion on the outer peripheral surface, and the reinforcing layer forms the tire frame body. Can be configured by winding a coated cord member formed by coating a reinforcing cord with the same or separate resin material in the circumferential direction of the tire frame body.
Thus, the circumferential direction rigidity of a tire frame body can be improved by constituting the perimeter part of a tire frame body with the reinforcement layer constituted by winding a covering cord member in the circumferential direction of a tire frame body.

(2-4) In the tire of the present invention, a thermoplastic resin material can be used as the resin material constituting the coated cord member.
In this way, by using a thermoplastic material having thermoplasticity as the resin material constituting the coated cord member, the tire can be easily manufactured and recycled as compared with the case where a thermosetting material is used as the resin material. It becomes easy.

(2-5) The tire of the present invention can be configured to roughen a region wider than the layered region of the tire constituent rubber members in the roughening treatment step.
As described above, in the roughening treatment step, when the roughening treatment is performed on a region wider than the lamination region of the tire constituent rubber members, the bonding strength between the tire frame body and the tire constituent rubber members can be reliably ensured.

(2-6) The tire of the present invention can be configured to roughen the outer peripheral surface so that the arithmetic average roughness Ra is 0.05 mm or more in the roughening treatment step.
As described above, when the outer peripheral surface of the tire frame body is roughened so that the arithmetic average roughness Ra is 0.05 mm or more in the roughening treatment step, the outer peripheral surface subjected to the roughening treatment, for example, via a bonding agent, When the unvulcanized or semi-cured tire component rubber member is laminated and vulcanized, the rubber of the tire component rubber member can be poured to the bottom of the roughened irregularities formed by the roughening treatment. When the rubber of the tire constituent rubber member is poured into the bottom of the roughened unevenness, a sufficient anchor effect is exerted between the outer peripheral surface and the tire constituent rubber member, and the bonding strength between the tire skeleton and the tire constituent rubber member Can be improved.

(2-7) In the tire of the present invention, unvulcanized or semi-vulcanized rubber can be used as the tire constituent rubber member.
As described above, when an unvulcanized or semi-vulcanized rubber is used as the tire constituent rubber member, when the tire constituent rubber member is vulcanized, a roughening process formed on the outer peripheral surface of the tire frame body. Rubber flows into the uneven surface. When the vulcanization is completed, the anchor effect is exhibited by the rubber (vulcanized) that has flowed into the roughened unevenness, and the bonding strength between the tire frame body and the tire constituting rubber member can be improved.

  In addition, vulcanized means the state that has reached the degree of vulcanization required for the final product, and the semi-vulcanized state has a higher degree of vulcanization than the unvulcanized state, but is required for the final product. This means that the degree of vulcanization is not reached.

(2-8) The tire of the present invention is formed using a thermoplastic resin material, and an annular tire skeleton body in which the outer peripheral surface is roughened by colliding a particulate projection material with the outer peripheral surface, and the roughening And a tire constituting rubber member laminated on the treated outer peripheral surface via a bonding agent.
As described above, when the roughened tire skeleton body is used, the bonding strength between the tire skeleton body and the tire constituting rubber member can be improved by the anchor effect. Moreover, since the outer peripheral surface is roughened, the wettability of the bonding agent is good. As a result, the bonding agent is held in a uniform application state on the outer peripheral surface of the tire frame body, the bonding strength between the tire frame body and the tire component rubber member is ensured, and the tire frame body and the tire component rubber member are separated. Can be suppressed.

[Examples 1 to 4, Comparative Examples 1 to 6]
Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to this.
First. According to the first embodiment described above, tires of examples and comparative examples were molded. At this time, the materials described in Table 1 below were used as materials for forming the tire case. In addition, a sample piece of 127 mm × 12.7 mm and a thickness of 1.6 mm, which has the same component composition as the tire case formed under the same conditions as the examples and comparative examples, was prepared, and the tensile strength, breaking elongation, and tensile elasticity were produced. The rate was evaluated.
The preparation method of each sample piece, each evaluation method, and evaluation conditions are as follows.

<Preparation of sample piece>
(A) Polyester-based thermoplastic elastomer 1) Made by Toray DuPont, Hytrel 3046
2) Made by Toray DuPont, Hytrel 5557
3) Hytrel 6347, manufactured by Toray DuPont Co., Ltd.
4) Made by Toray DuPont, Hytrel 7247
5) Made by Toray DuPont, Hytrel 2751
(B) Polyester resin (polybutylene terephthalate resin)
1) DURANEX 2000, manufactured by Polyplastics Co., Ltd.
2) Made of Polyplastics, Juranex 2002
(C) Comparative resin (acrylonitrile / butadiene / styrene copolymer)
1) Techno ABS manufactured by Techno Polymer Co., Ltd.

-Elastic modulus of polyester resin-
(B) Using the above-mentioned various resins shown as the polyester resin as a molding material, a sample piece was produced by injection molding using a 127 mm × 12.7 mm mold with a thickness of 1.6 mm. The molding conditions are as follows.
・ Injection molding machine: SE30D, Sumitomo Heavy Industries, Ltd.
Molding temperature (temperature of thermoplastic resin material): 200 ° C to 240 ° C
-Mold temperature: 40 ° C-60 ° C
The tensile modulus of the test piece was examined by pulling the obtained test piece with a Shimadzu Corporation, Shimadzu Autograph, AGS-J (5KN) at a tensile speed of 1 mm / min. Results were obtained.

(B) Polyester resin (polybutylene terephthalate resin)
1) Polyplastics Co., Ltd., DURANEX 2000, elastic modulus = 1100 MPa
2) Polyplastic Co., Ltd., Juranex 2002, elastic modulus = 1250 MPa

  The above-described polyester-based thermoplastic elastomer and polyester resin were mixed (mass basis) with the composition shown in Table 1, and kneaded by a LABOPLASTOMILL 50MR twin screw extruder manufactured by Toyo Seiki Seisakusho to obtain pellets. In Comparative Examples 1 to 4, pellets made of a polyester thermoplastic elastomer shown in Table 1 were prepared without using a mixed system.

Using the prepared pellets of the example and the comparative example, injection molding was performed under the following conditions to obtain a sample piece having a thickness of 1.6 mm.
For injection molding, SE30D manufactured by Sumitomo Heavy Industries, Ltd. is used, and a mold temperature of 200 ° C. to 235 ° C. and a mold temperature of 50 ° C. to 70 ° C. are 127 mm × 12.7 mm and a thickness of 1.6 mm. Was used.

<Evaluation method>
1. Evaluation of Tensile Strength, Breaking Elongation, and Tensile Elastic Modulus A sample piece obtained by the injection molding was punched out to prepare a dumbbell-shaped test piece (No. 5 type test piece) defined in JIS K6251: 1993.
Tensile strength, elongation at break, and tensile modulus are obtained by using Shimadzu Corporation, Shimadzu Autograph, AGS-J (5KN), and pulling the obtained dumbbell-shaped test piece at a pulling speed of 200 mm / min. It was measured by.

2. Tan δ Measurement A loss tangent (tan δ) at a temperature of 30 ° C., a measurement frequency of 20 Hz, and a dynamic strain of 1% was measured using a dynamic viscoelasticity measurement tester “ARES III” manufactured by Rheometrics.

  Table 1 shows the tensile strength, elongation at break, tensile elastic modulus, and tan δ of each sample piece of Examples and Comparative Examples.

3. Relationship between Elastic Modulus (Tensile Elastic Modulus) and tan δ The relationship between the tensile elastic modulus and tan δ of the sample pieces of Examples 1 to 4 and Comparative Examples 1 to 5 was plotted in FIG.

As shown in Table 1, the evaluation result of the sample piece produced in the example is an index showing the rolling resistance of the tire regardless of the change in the tensile modulus in comparison with the evaluation result of the sample piece of the comparative example. Since the fluctuation range of tan δ is small, it can be seen that the increase in rolling resistance is suppressed.
This can also be grasped from FIG. FIG. 6 plots tan δ against tensile modulus. The regression line (not shown) grasped from the plots of Comparative Examples 1 to 6 has a large slope and the tan δ increases as the tensile modulus increases, but is understood from the plots of Examples 1 to 4. It can be seen that the regression line (not shown) has a small slope and tan δ is unlikely to increase even if the tensile elastic modulus increases.
Moreover, it turns out that each sample piece produced in the Example sufficiently satisfies the level required for the tire in all of the tensile strength, breaking elongation, and tensile elastic modulus. This is because the tire manufactured using the tire case formed using the same thermoplastic resin material as the sample pieces of Examples 1 to 4 is suppressed in increase in rolling resistance and excellent in durability. Indicates that Furthermore, it is assumed that an automobile configured using such tires has good fuel efficiency.

  In addition, when the drum running test was done about each tire formed using each thermoplastic resin material of an Example and a comparative example, the safety | security on driving | running | working did not have any problem.

10, 200 Tire 12 Bead part 16 Crown part (outer peripheral part)
18 Bead core 20 Rim 21 Bead sheet 22 Rim flange 17 Tire case (tire frame)
24 Seal layer (seal part)
26 Reinforcement cord (reinforcement cord member)
26A cord member (reinforcing cord member)
28 Reinforcing cord layer 30 Tread D Diameter of reinforcing cord (diameter of reinforcing cord member)
L Embedding amount of reinforcement cord (embedding amount of reinforcement cord member)

Claims (3)

A tire having an annular tire skeleton formed of a thermoplastic resin material, wherein the thermoplastic resin material includes a polyester-based thermoplastic elastomer (A) having a hard segment and a soft segment containing a polyester resin, and thermoplasticity an elastomer other than the polyester resin (B), only contains,
The mass ratio (A: B) of the polyester-based thermoplastic elastomer (A) and the polyester resin (B) other than the thermoplastic elastomer is 95: 5 to 50:50,
The tire whose content of the said polyester-type thermoplastic elastomer (A) in the said thermoplastic resin material is 50 mass%-95 mass% .   The tire according to claim 1, wherein the elastic modulus of the polyester resin (B) is 700 MPa or more. The tire according to claim 1 or 2 , further comprising a reinforcing cord member that is wound around an outer peripheral portion of the tire frame body in a circumferential direction to form a reinforcing cord layer.