JP6639201B2 - tire - Google Patents

Description

  The present invention relates to a tire.

In recent years, use of a resin material, particularly a thermoplastic resin or a thermoplastic elastomer, as a tire material has been studied from the viewpoint of weight reduction, ease of molding, and ease of recycling.
Particularly, due to its high heat resistance and small rolling resistance, Patent Document 1 has made many studies to use a resin material having an amide bond or an ester bond as a tire material.

JP 2012-046030 A

Many of the tires using a resin material use a resin material having an amide bond or an ester bond in a tire frame or a reinforcing cord member, and when using a tire using such a resin material, High economic efficiency such as enduring long-term use is required. Physical properties that directly affect the economy of a tire include the rolling resistance of the tire.
On the other hand, when the tire is used for a long time, it is assumed that the tire is placed in a high-temperature and high-humidity environment. Under such conditions, a resin material having an amide bond or an ester bond is used. It has been found that the rolling resistance of tires that have been used deteriorates as the period of use increases.

  However, when a tire using such a resin material is exposed to high-temperature and high-humidity conditions (moist heat conditions), it is often unknown how the rolling resistance of the tire changes. No solution has yet been proposed.

  In view of the above situation, an object of the present invention is to provide a tire in which an increase in rolling resistance is suppressed even when exposed to wet heat conditions.

<1> At least (A) a resin material having at least one of an amide bond and an ester bond, and (B) a carbodiimide compound, wherein the content of the carbodiimide compound is 0.3 mass with respect to 100 parts by mass of the resin material. A tire having a tire skeleton formed of a resin composition in an amount of at least 6 parts by mass and less than 6 parts by mass.

<2> The tire according to <1>, wherein the resin material includes at least one resin selected from a polyamide thermoplastic elastomer, a polyester thermoplastic elastomer, a polyamide resin, and a polyester resin.

<3> The tire further includes a reinforcing cord member that forms a reinforcing cord layer by being circumferentially wound around an outer peripheral portion of the tire frame body, and the reinforcing cord member is at least coated with a coating resin. > Or the tire according to <2>.

<4> The tire according to <3>, wherein the coating resin is the resin material.

<5> The tire according to <3>, wherein the coating resin is the resin composition.

  The present invention can provide a tire in which an increase in rolling resistance is suppressed even when exposed to wet heat conditions.

(A) is a perspective view showing a partial cross section of the tire according to the first embodiment of the present invention, and (B) is a cross sectional view of a bead portion mounted on a rim. FIG. 2 is a cross-sectional view along a tire rotation axis showing a state in which a reinforcing cord is embedded in a crown portion of a tire case of the tire according to the first 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 a cross-sectional view along a tire width direction of a tire according to a second embodiment of the present invention, and (B) is a cross-section along a tire width direction of a bead portion with a rim fitted to the tire. FIG. It is sectional drawing along the tire width direction which shows the periphery of the reinforcement layer of the tire of 2nd Embodiment.

  The tire of the present invention includes at least (A) a resin material having at least one of an amide bond and an ester bond, and (B) a carbodiimide compound, wherein the content of the carbodiimide compound is 0 with respect to 100 parts by mass of the resin material. It has a tire skeleton formed from a resin composition of not less than 3 parts by mass and less than 6 parts by mass.

  In using a tire, it is assumed that the resin material used for the tire frame is often affected by water during long-term use. In particular, when a tire having a tire skeleton formed of a resin material having an ester bond or an amide bond is exposed to wet heat conditions, there is a problem that the rolling resistance of the tire increases. For this reason, there is a concern that an automobile using a tire made of such a resin material will have increased rolling resistance and deteriorated fuel efficiency after long-term use. In addition, such tires have a problem in terms of durability, because when exposed to wet heat conditions, there is a concern that the resin may deteriorate due to heat generation.

  In a tire, when the loss tangent (tan δ) of the resin composition (tire frame) increases, the energy loss (heat generation) generated by deformation when the tire rolls increases, and the rolling resistance tends to increase. . Even in a tire having a tire skeleton formed of a resin material having an ester bond or an amide bond, after being exposed to wet heat for a long period of time, rolling resistance increases and tan δ tends to increase. .

  However, since the carbodiimide compound is contained in the resin composition (the resin composition forming the tire skeleton) of the present invention, even after the tire is exposed to wet heat conditions (after the passage of wet heat conditions), the tire composition can be used. An increase in tan δ of the skeleton is suppressed. In addition, tan δ after exposure to wet heat conditions can be reduced rather than tan δ before exposure to wet heat conditions. For this reason, in the tire of the present invention, there is an effect that the rolling resistance as the tire is maintained or improved even after being exposed to wet heat conditions.

In the present specification, tan δ is measured by using a commercially available viscoelasticity measuring tester (manufactured by Rheometrics) after preparing a dumbbell-shaped test piece (No. 5 test piece) specified in JIS K6251 (1993). It can be obtained by measuring at 30 ° C., 1% strain, and 20 Hz frequency.
The rolling resistance of the tire is measured using a drum tester having a steel plate surface of a predetermined size, by assembling the tire with a predetermined rim conforming to JATMA, rolling the tire at a predetermined internal pressure, load load and speed. can do.
Further, “exposed under moist heat conditions” in this specification means that the target tire or tire frame (resin composition forming the resin composition) is 40 ° C. or more and has a humidity of 60% RH (relative humidity 60%). %) Or more for at least 100 hours in total.

  First, a description will be given of (A) a resin material having at least one of an amide bond and an ester bond (hereinafter, referred to as a specific resin material) and (B) a carbodiimide compound to be added thereto, which constitute the tire skeleton according to the present invention. Next, specific embodiments of the tire of the present invention will be described with reference to the drawings.

(Specific resin material)
The specific resin material refers to a material containing an amide bond or an ester bond, or both an amide bond and an ester bond in a polymer molecule in the resin material. In this case, the specific resin material may contain a polymer having either an amide bond or an ester bond, or a polymer having an amide bond and a polymer having an ester bond other than the polymer having the amide bond. May be mixed.
As the specific resin material, any resin having at least one of an amide bond and an ester bond may be used as long as the effect of the present invention is not impaired, such as a thermoplastic resin (including a thermoplastic elastomer) and a thermosetting resin. In particular, from the viewpoint of further reducing the rolling resistance of the tire, it is preferable to include at least one selected from a thermoplastic elastomer, a polyamide resin, and a polyester resin. Here, the polyamide resin and the polyester resin refer to resins other than the thermoplastic elastomer. Examples of the polyamide resin and the polyester resin include those used as thermosetting resins, thermoplastic resins (excluding thermoplastic elastomers), and engineering plastics. Further, as described later, examples of the thermoplastic elastomer of the specific resin material include a polyamide-based thermoplastic elastomer and a polyester-based thermoplastic elastomer.
Further, among the specific resin materials, the details of the polyamide-based thermoplastic elastomer, the polyester-based thermoplastic elastomer, the polyamide resin, and the polyester resin will be described below.
In the present specification, “resin” does not include vulcanized rubber.

  The content of the specific resin material is preferably 30% by mass or more based on the total amount of the resin composition. When the content is 30% by mass or more based on the total amount of the resin composition, the characteristics of the resin material can be sufficiently exhibited, and the rolling resistance of the tire can be further reduced. Further, the content of the specific resin material is more preferably 50% by mass or more, and particularly preferably 70% by mass or more.

(Polyamide resin)
The polyamide resin is not particularly limited as long as the effects of the present invention are not impaired. Examples of the polyamide resin include polyamide (amide 6) obtained by ring-opening polycondensation of ε-caprolactam, polyamide (amide 11) obtained by ring-opening polycondensation of undecanelactam, and polyamide (amide 12) obtained by ring-opening polycondensation of lauryl lactam. And a polyamide (amide 66) obtained by polycondensing a diamine and a dibasic acid or a polyamide (amide MX) having meta-xylene diamine as a structural unit.

As the polyamide-based resin that is not a thermoplastic elastomer, a commercially available product may be used.
Examples of the amide 6 include, for example, a commercially available product “UBE nylon” 1022B manufactured by Ube Industries, Ltd.
, 1011FB or the like can be used. As the amide 12, for example, "UBE nylon" manufactured by Ube Industries, 3024U or the like can be used. As the amide 66, "UBE nylon 2020B" or the like can be used. Further, as the amide MX, for example, commercially available MX nylon (S6001, S6021, S6011) manufactured by Mitsubishi Gas Chemical Company or the like can be used.

(Polyester resin)
The polyester resin may be crystalline or amorphous, and examples thereof include aliphatic polyesters and aromatic polyesters. The aliphatic polyester may be a saturated aliphatic polyester or an unsaturated aliphatic polyester.
Examples of the aromatic polyester include polyethylene terephthalate, polybutylene terephthalate, polystyrene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and the like, and polybutylene terephthalate is preferable.
As the aliphatic polyester, any of a dicarboxylic acid / diol condensation system and a hydroxycarboxylic acid condensation system can be used. For example, polylactic acid, polyhydroxy-3-butylbutyric acid, polyhydroxy-3-hexylbutyric acid, poly (ε-caprolactone), polyenantholactone, polycaprylolactone, polybutylene adipate, polyethylene adipate and the like can be mentioned.

  As the polyester resin as described above, commercially available products can be used. 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.) and "Toraycon" series (for example, 1401X06, 1401X31, etc.) manufactured by Toray Industries, Inc.

(Thermoplastic elastomer)
Examples of the thermoplastic elastomer include a polyolefin-based thermoplastic elastomer (TPO), a polystyrene-based thermoplastic elastomer (TPS), a polyamide-based thermoplastic elastomer (TPA), and a polyurethane-based thermoplastic elastomer (including at least one of an amide bond and an ester bond). TPU), polyester-based thermoplastic elastomer (TPC), and dynamically crosslinked thermoplastic elastomer (TPV).
The thermoplastic elastomer is a polymer compound which becomes relatively hard and strong when the material softens and flows as the temperature rises and cools, and has a rubber-like elasticity.
Among the above thermoplastic elastomers, a polyamide thermoplastic elastomer (TPA) and a polyester thermoplastic elastomer (TPC) are preferable.

(Polyamide thermoplastic elastomer)
"Polyamide-based thermoplastic elastomer" is a thermoplastic resin material consisting of a copolymer having a hard segment derived from a polymer having a high melting point which is crystalline and a soft segment derived from an amorphous polymer having a low glass transition temperature. A polymer having an amide bond (—CONH—) in the main chain of the polymer forming the hard segment can be used. Examples of the polyamide-based thermoplastic elastomer include, for example, an amide-based thermoplastic elastomer (TPA) specified in JIS K6418: 2007, and a polyamide-based thermoplastic elastomer described in JP-A-2004-346273. .
Further, the polyamide-based thermoplastic elastomer in the present invention may include a polymer having an ester bond.

  In the polyamide-based thermoplastic elastomer, at least the polyamide constitutes a hard segment having a high melting point which is crystalline and another polymer (eg, polyester or polyether) constitutes a soft segment having an amorphous and low glass transition temperature. Materials. The polyamide-based thermoplastic elastomer may use a chain extender such as dicarboxylic acid in addition to the hard segment and the soft segment. As the polyamide forming the hard segment, for example, a polyamide produced by a monomer represented by the following general formula (1) or (2) can be exemplified.

−Hard segment−
Examples of the polyamide forming the hard segment include polyamides synthesized using a monomer represented by the following general formula (1) or (2).

In the general formula (1), R ¹ represents a molecular chain of an aliphatic hydrocarbon having 2 to 20 carbon atoms (preferably a saturated aliphatic hydrocarbon). Examples of the molecular chain of the aliphatic hydrocarbon having 2 to 20 carbon atoms include an alkylene group having 2 to 20 carbon atoms.

In the general formula (2), R ² represents a molecular chain of an aliphatic hydrocarbon having 3 to 20 carbon atoms (preferably a saturated aliphatic hydrocarbon). Examples of the molecular chain of the aliphatic hydrocarbon having 3 to 20 carbon atoms include an alkylene group having 3 to 20 carbon atoms.

In the general formula (1), R ¹ is preferably a molecular chain of an aliphatic hydrocarbon having 3 to 18 carbon atoms (for example, an alkylene group having 3 to 18 carbon atoms), and an aliphatic hydrocarbon having 4 to 15 carbon atoms. (For example, an alkylene group having 4 to 15 carbon atoms) is more preferable, and a molecular chain of an aliphatic hydrocarbon having 10 to 15 carbon atoms (for example, an alkylene group having 10 to 15 carbon atoms) is particularly preferable. Further, in the general formula (2), as R ² , a molecular chain of an aliphatic hydrocarbon having 3 to 18 carbon atoms (for example, an alkylene group having 3 to 18 carbon atoms) is preferable, and an aliphatic hydrocarbon having 4 to 15 carbon atoms is preferable. A hydrocarbon molecular chain (for example, an alkylene group having 4 to 15 carbon atoms) is more preferable, and a molecular chain of an aliphatic hydrocarbon having 10 to 15 carbon atoms (for example, an alkylene group having 10 to 15 carbon atoms) is particularly preferable. Examples of the monomer represented by the general formula (1) or (2) include ω-aminocarboxylic acid and lactam.
Examples of the polyamide forming the hard segment include polycondensates of these ω-aminocarboxylic acids and lactams, and copolycondensates of diamines and dicarboxylic acids.

  Examples of the ω-aminocarboxylic acid include 5 to 20 carbon atoms such as 6-aminocaproic acid, 7-aminoheptanoic acid, 8-aminooctanoic acid, 10-aminocapric acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Aliphatic ω-aminocarboxylic acid, etc. Examples of the lactam include aliphatic lactams having 5 to 20 carbon atoms such as lauryl lactam, ε-caprolactam, undecane lactam, ω-enantholactam, and 2-pyrrolidone.

Examples of the diamine include ethylene diamine, trimethylene diamine, tetramethylene diamine, hexamethylene diamine, heptamethylene diamine, octamethylene diamine, nonamethylene diamine, decamethylene diamine, undecamethylene diamine, dodecamethylene diamine, and 2,2. Examples thereof include diamine compounds such as aliphatic diamines having 2 to 20 carbon atoms such as 4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 3-methylpentamethylenediamine, and metaxylenediamine.
Further, dicarboxylic _{^{acids, HOOC- (R 3) m -COOH}} (R 3: the molecular chain of a hydrocarbon of 3 to 20 carbon atoms, m: 0 or 1) can be represented by, for example, oxalic acid, succinic acid And aliphatic dicarboxylic acids having 2 to 22 carbon atoms such as glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid and dodecane diacid.

  Examples of the polyamide forming the hard segment include a polyamide obtained by ring-opening polycondensation of ε-caprolactam (polyamide 6), a polyamide obtained by ring-opening polycondensation of undecanelactam (polyamide 11), and a polyamide obtained by ring-opening polycondensation of lauryl lactam (polyamide) 12), polyamide (polyamide 12) obtained by polycondensation of 12-aminododecanoic acid, polycondensation polyamide (polyamide 66) of diamine and dibasic acid or polyamide (amide MX) having metaxylenediamine as a constitutional unit. Can be.

The polyamide 6 can be represented by, for example, {CO— (CH ₂ ) ₅ —NH} _n (n represents an arbitrary number of repeating units). For example, n is preferably 2 to 100, and preferably 3 to 50. Is more preferred.
The polyamide 11 can be represented, for example, by {CO— (CH ₂ ) ₁₀ —NH} _n (n represents an arbitrary number of repeating units). For example, n is preferably 2 to 100, and preferably 3 to 50. Is more preferred.
The polyamide 12 can be represented by, for example, {CO— (CH ₂ ) ₁₁ —NH} _n (n represents an arbitrary number of repeating units). For example, n is preferably 2 to 100, and preferably 3 to 50. Is more preferred.
The polyamide 66 can be represented by, for example, {CO (CH ₂ ) ₄ CONH (CH ₂ ) ₆ NH} _n (n represents an arbitrary number of repeating units). For example, n is preferably 2 to 100. And 3 to 50 are more preferable.

  Further, the amide MX having meta-xylenediamine as a structural unit can be represented, for example, by the following structural unit (A-1) [where n represents an arbitrary number of repeating units in (A-1)]. 2-100 are preferable, and 3-50 are more preferable.

The polyamide thermoplastic elastomer, as a hard _{segment, - [CO- (CH 2)} 11 -NH] - It is preferred to have the polyamide (polyamide 12) having a unit structure represented by. As described above, polyamide 12 can be obtained by ring-opening polycondensation of lauryl lactam or polycondensation of 12-aminododecanoic acid.

−Soft segment−
Examples of the polymer forming the soft segment include polyester and polyether. Further, for example, polyethers such as polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol (PTMG) and polyester polyol, and ABA-type triblock polyether diols may be mentioned. These can be used alone or in combination of two or more. Further, a polyether diamine or the like obtained by reacting ammonia or the like with the terminal of the polyether can be used. For example, an ABA-type triblock polyether diamine can be used.

  Here, the “ABA-type triblock polyether diol” includes a polyether represented by the following general formula (3).

  In the general formula (3), x and z each independently represent an integer of 1 to 20. y represents an integer of 4 to 50.

  In the general formula (3), each of x and z is preferably an integer of 1 to 18, more preferably an integer of 1 to 16, particularly preferably an integer of 1 to 14, and most preferably an integer of 1 to 12. . In the general formula (3), y is preferably an integer of 5 to 45, more preferably an integer of 6 to 40, particularly preferably an integer of 7 to 35, and most preferably an integer of 8 to 30.

  The “ABA-type triblock polyether diamine” includes polyether diamines represented by the following general formula (N).

In the general formula (N), _{X N} and _{Z N} represent each independently an integer of 1-20. Y _N represents an integer of 4-50.

In the general formula (N), each of X _N and Z _N is preferably an integer of 1 to 18, more preferably an integer of 1 to 16, particularly preferably an integer of 1 to 14, and an integer of 1 to 12. Most preferred. Further, in the general formula (N), as the _{Y N,} preferably an integer of 5-45, more preferably an integer of 6 to 40, particularly preferably an integer of 7-35, and most preferably an integer of 8-30.

  Examples of the combination of the hard segment and the soft segment include the respective combinations of the hard segment and the soft segment described above. Of these, lauryl lactam ring-opening polycondensate / polyethylene glycol combinations, lauryl lactam ring-opening polycondensates / polypropylene glycol combinations, lauryl lactam ring-opening polycondensates / polytetramethylene ether glycol combinations, lauryl lactam Combination of ring opening polycondensate / ABA type triblock polyether diol, polycondensate of aminododecanoic acid / polyethylene glycol, polycondensate of aminododecanoic acid / polypropylene glycol, polycondensate of aminododecanoic acid / A combination of polytetramethylene ether glycol and a polycondensate of aminododecanoic acid / ABA triblock polyether diol is preferred, and a combination of a ring-opening polycondensate of lauryl lactam / ABA triblock polyether diol Polycondensate / ABA type combination of a triblock polyether diols amino dodecanoic acid, are particularly preferred. These combinations are preferably selected so that the polyamide-based thermoplastic elastomer in the present invention has an ester bond in the molecule.

  The polymer forming the soft segment may contain a diamine such as a branched saturated diamine having 6 to 22 carbon atoms, a branched alicyclic diamine having 6 to 16 carbon atoms, or norbornane diamine as a monomer unit. Further, these branched saturated diamines having 6 to 22 carbon atoms, branched alicyclic diamines having 6 to 16 carbon atoms, or norbornanediamine may be used alone or in combination. However, it is preferable to use in combination with the above-mentioned ABA-type triblock polyether diol.

  Examples of the branched saturated diamine having 6 to 22 carbon atoms include 2,2,4-trimethyl-1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, and 1,2-diamine. Examples thereof include diaminopropane, 1,3-diaminopentane, 2-methyl-1,5-diaminopentane, and 2-methyl-1,8-diaminooctane.

  Examples of the branched alicyclic diamine having 6 to 16 carbon atoms include 5-amino-2,2,4-trimethyl-1-cyclopentanemethylamine and 5-amino-1,3,3-trimethylcyclohexanemethylamine And the like. These diamines may be either cis or trans, or a mixture of these isomers.

  Examples of the norbornanediamine include 2,5-norbonanedimethylamine, 2,6-norbonanedimethylamine, and mixtures thereof.

Further, the polymer constituting the soft segment may include a diamine compound other than the above as a monomer unit. As other diamine compounds, for example, ethylene diamine, trimethylene diamine, tetramethylene diamine, hexamethylene diamine, heptamethylene diamine, octamethylene diamine, nonamethylene diamine, decamethylene diamine, undecamethylene diamine, dodecamethylene diamine, 2, Aliphatic diamines such as 2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 3-methylpentanemethylenediamine, bis (4-aminocyclohexyl) methane, bis (4-aminocyclohexyl) propane, Alicyclic diamines such as 1,3-bisaminomethylcyclohexane and 1,4-bisaminomethylcyclohexane, and aromatic diamines such as meta-xylylenediamine and para-xylylenediamine And the like.
The above-mentioned diamines may be used alone or in combination of two or more.

-Chain length extender-
As described above, the polyamide-based thermoplastic elastomer may use a chain extender such as a dicarboxylic acid, in addition to the hard segment and the soft segment. As the dicarboxylic acid, for example, at least one selected from aliphatic, alicyclic, and aromatic dicarboxylic acids or derivatives thereof can be used.

  Specific examples of the dicarboxylic acid include adipic acid, decane dicarboxylic acid, oxalic acid, succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, and linear C2-25 acid. Aliphatic dicarboxylic acids; aliphatic dicarboxylic acids such as dimerized aliphatic dicarboxylic acids having 14 to 48 carbon atoms obtained by dimerizing unsaturated fatty acids obtained by fractionation of triglycerides, and hydrogenated products thereof; 1,4-cyclohexanedicarboxylic acid; Examples include alicyclic dicarboxylic acids such as acids and aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid.

~ Polyamide-based thermoplastic elastomer having ester bond ~
As the specific resin material, a polyamide thermoplastic elastomer containing an ester bond can be used. The use of such a specific resin material is advantageous because the rolling resistance of the tire can be further reduced and the rim assemblability can be further improved. The ester bond may be in any of the hard segment and the soft segment of the polyamide-based thermoplastic elastomer, but as the soft segment, a copolymer containing a polyester such as a polyester polyol may be used, or as the soft segment. A diol compound having a hydroxyl group at both terminals such as polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol (PTMG) or the above-mentioned ABA-type triblock polyether diol, and a polycarboxylic acid as a chain extender ( A dicarboxylic acid) and may have an ester bond contained in a structural unit derived from these condensation polymers. In view of the above, the polyamide thermoplastic elastomer of the present invention contains a diol compound as a soft segment, and is derived from a bond between a hydroxyl group of the diol compound and a carboxyl group (for example, in a hard segment or a chain extender). It is preferable to include an ester bond. Examples of the diol compound include, but are not particularly limited to, the above-mentioned glycols and diols. Specifically, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol (PTMG), and the above-mentioned general formula A diol compound having a hydroxyl group at both terminals selected from the ABA-type triblock polyether diols represented by (3) can be mentioned. For example, an ABA-type triblock polyether diol or PTMG can be used.

  In addition, as a raw material for the polyamide-based thermoplastic elastomer, by selecting the type and the amount of the heart segment, the soft segment and the chain length extender, and controlling the amount of ester bond generated in the polymerization reaction between the raw materials. Can be. For example, when synthesizing a polyamide-based thermoplastic elastomer having the above-mentioned polyamide 12 as a hard segment, lauryl lactam is used as a raw material for the hard segment using ring-opening polycondensation or 12-aminododecanoic acid, and PTMG or the above is used as a raw material for the soft segment. Having an ester bond by performing a synthetic reaction using a diol compound selected from ABA-type triblock polyether diols represented by the general formula (3) and using adipic acid or decanedicarboxylic acid as a chain extender. A polyamide-based thermoplastic elastomer can be synthesized.

(HS mass ratio)
The mass ratio (HS / SS) between the hard segment (HS) and the soft segment (SS) of the above-mentioned polyamide-based thermoplastic elastomer is not particularly limited, and is preferably adjusted appropriately. For example, when the HS mass ratio is 10/90 to 90/10, a more appropriate elastic modulus can be obtained, and the rim assemblability can be further improved. The HS mass ratio can be adjusted to a desired range by setting the charged amounts of the raw material constituting the hard segment and the raw material constituting the soft segment. Further, the HS mass ratio can be measured by using ¹ H-NMR for the polyamide thermoplastic elastomer.

When the chain extender is used, its content is preferably set so that the hydroxyl group or amino group of the monomer constituting the soft segment and the carboxyl group of the chain extender are substantially equimolar.
The content of the hard segment, the soft segment and the chain extender used as needed in the polyamide-based thermoplastic elastomer are appropriately selected, for example, each content is set to a desired content by setting the charged amount. be able to.

  The weight average molecular weight of the polyamide thermoplastic elastomer contained in the specific resin material is not particularly limited, but is preferably about 10,000 to 400,000. From the viewpoint of further improving the rim assemblability and improving the pressure resistance against the internal pressure of the tire, the weight average molecular weight of the polyamide-based thermoplastic elastomer is preferably 15,700 to 300,000, and 22,000 to 200,000. More preferred. The weight average molecular weight of the polyamide-based thermoplastic elastomer can be measured by gel permeation chromatography (GPC). For example, GPC (gel permeation chromatography) such as “HLC-8320GPC EcoSEC” manufactured by Tosoh Corporation can be used. Can be used.

  The number average molecular weight of the polymer (polyamide) constituting the hard segment is preferably from 300 to 15,000 from the viewpoint of melt moldability. The number average molecular weight of the polymer constituting the soft segment is preferably from 200 to 6000 from the viewpoint of toughness and flexibility at low temperature. These number average molecular weights can be determined by the GPC measurement.

  The polyamide-based thermoplastic elastomer can be synthesized by copolymerizing the polymer forming the hard segment and the polymer forming the soft segment by a known method. For example, the polyamide-based thermoplastic elastomer includes a monomer constituting a hard segment (for example, an ω-aminocarboxylic acid such as 12-aminododecanoic acid or a lactam such as lauryl lactam) and a monomer constituting a soft segment (for example, It can be obtained by polymerizing the ABA-type triblock polyether diol) and a chain extender (for example, adipic acid or decanedicarboxylic acid) in a container. In particular, when ω-aminocarboxylic acid is used as a monomer constituting the hard segment, it can be synthesized by performing normal-pressure melt polymerization or normal-pressure melt polymerization and further performing low-pressure melt polymerization. When using a lactam as a monomer constituting the hard segment, a suitable amount of water can be allowed to coexist, and a method comprising melt polymerization under pressure of 0.1 to 5 MPa, followed by normal pressure melt polymerization and reduced pressure melt polymerization. Can be manufactured. Further, these synthesis reactions can be carried out in either a batch system or a continuous system. In the above-mentioned synthesis reaction, a batch reactor, a single- or multi-tank continuous reactor, a tubular continuous reactor, or the like may be used alone or in an appropriate combination.

  In the production of the polyamide thermoplastic elastomer, the polymerization temperature is preferably from 150 to 300C, more preferably from 160 to 280C. The polymerization time can be appropriately determined depending on the relationship between the polymerization average molecular weight and the polymerization temperature of the polyamide thermoplastic elastomer to be synthesized. For example, 0.5 to 30 hours is preferable, and 0.5 to 20 hours is more preferable.

In the production of the polyamide-based thermoplastic elastomer, a monoamine or diamine such as laurylamine, stearylamine, hexamethylenediamine, or metaxylylenediamine, for the purpose of adjusting the molecular weight or stabilizing the melt viscosity during molding as required. An additive such as monocarboxylic acid such as acetic acid, benzoic acid, stearic acid, adipic acid, sebacic acid and dodecane diacid, or dicarboxylic acid may be added. These additives can be appropriately selected depending on the relationship between the molecular weight and the viscosity of the obtained polyamide thermoplastic elastomer within a range not adversely affecting the effects of the present invention.
In the production of the polyamide thermoplastic elastomer, a catalyst can be used if necessary. The catalyst includes at least one selected from the group consisting of P, Ti, Ge, Zn, Fe, Sn, Mn, Co, Zr, V, Ir, La, Ce, Li, Ca, and Hf. Compounds.
For example, an inorganic phosphorus compound, an organic titanium compound, an organic zirconium compound, an organic tin compound and the like can be mentioned.
Specifically, examples of the inorganic phosphorus compound include phosphorus-containing acids such as phosphoric acid, pyrophosphoric acid, polyphosphoric acid, phosphorous acid, and hypophosphorous acid, alkali metal salts of phosphorus-containing acids, and alkaline earth salts of phosphorus-containing acids. Metal salts and the like.
Examples of the organic titanium compound include titanium alkoxide (titanium tetrabutoxide, titanium tetraisopropoxide, etc.).
Examples of the organic zirconium compound include zirconium alkoxide [zirconium tetrabutoxide (also referred to as “Zr (OBu) ₄ ” or “Zr (OC ₄ H ₈ ) ₄ )”) and the like.
Examples of the organotin compound include distannoxane compounds [such as 1-hydroxy-3-isothiocyanate-1,1,3,3-tetrabutyldistannoxane], tin acetate, dibutyltin dilaurate, and butyltin hydroxide oxide hydrate. No.
The catalyst addition amount and catalyst addition time are not particularly limited as long as the desired product can be obtained quickly.

  Examples of the polyamide thermoplastic elastomer include ring-opening polycondensate of lauryl lactam / polyethylene glycol / adipic acid, ring-opening polycondensate of lauryl lactam / polypropylene glycol / adipic acid, and ring-opening of lauryl lactam. Polycondensate / polytetramethylene ether glycol / adipic acid combination, lauryl lactam ring-opening polycondensate / ABA triblock polyether / adipic acid combination, lauryl lactam ring-opening polycondensate / polyethylene glycol / decanedicarboxylic acid Combination of acid, ring-opening polycondensate of lauryl lactam / polypropylene glycol / decanedicarboxylic acid, combination of ring-opening polycondensate of lauryl lactam / polytetramethylene ether glycol / decanedicarboxylic acid, lauryl lactate Combination of ring-opening polycondensate / ABA-type triblock polyether / decanedicarboxylic acid, polycondensate of aminododecanoic acid / polyethylene glycol / adipic acid, polycondensate of aminododecanoic acid / polypropylene glycol / adipic acid Combination, polycondensate of aminododecanoic acid / polytetramethylene ether glycol / adipic acid, polycondensate of aminododecanoic acid / ABA triblock polyether / adipic acid, polycondensate of aminododecanoic acid / polyethylene Glycol / decanedicarboxylic acid combination, aminododecanoic acid polycondensate / polypropylene glycol / decanedicarboxylic acid combination, aminododecanoic acid polycondensate / polytetramethylene ether glycol / decanedicarboxylic acid combination, aminododecanoic acid A combination of a polycondensate / ABA-type triblock polyether / decanedicarboxylic acid is preferable, a ring-opening polycondensate of lauryl lactam / ABA-type triblock polyether / adipic acid, a polycondensate of aminododecanoic acid / ABA type The combination of triblock polyether / adipic acid, the polycondensate of aminododecanoic acid / polytetramethylene ether glycol / adipic acid, the combination of polycondensate of aminododecanoic acid / polytetramethylene ether glycol / decanedicarboxylic acid are particularly preferred. preferable. As the above-mentioned polyamide-based thermoplastic elastomer, a combination of the above-described preferred embodiments in terms of a combination of structural units, a structural ratio, a molecular weight, and the like can be used.

Examples of the above-mentioned polyamide-based thermoplastic elastomer include, for example, commercially available polyether polyamide resins (Pebax2533, Pebax3533, Pebax4033, Pebax5533, Pebax6333, Pebax7033, Pebax7233, Pebax7033, Pebax7233, etc., manufactured by Arkema, and "U" manufactured by Ube Industries, Ltd. "XPA" series (for example, XPA9063X1, XPA9055X1, XPA9048X2, XPA9048X1, XPA9044, etc.), and "Vestamide" series (for example, E40-S3, E47-S1, E47-S3, E55-S1, E55) manufactured by Daicel Eponic Corporation. -S3, E55-S4, E55-K1W2, EX9200, E50-R2)) can be appropriately used.
These polyamide-based thermoplastic elastomers are thermoplastic elastomers obtained by condensation polymerization of a “polyether block amide” in which a polyamide block that is a hard segment and a polyether block that is a soft segment are bonded via an ester bond, that is, an ester bond. Polyamide-based thermoplastic elastomer. These polyamide-based thermoplastic elastomers have excellent kinetic properties and moldability, and further have good compatibility with carbodiimide compounds and other additives. For this reason, a resin composition (tire frame) containing the elastomer as a specific resin material is advantageous because tan δ can be reduced and the rolling resistance of a tire can be reduced.

  When a polyester-based thermoplastic elastomer is used as the resin material, the content of the polyester-based thermoplastic elastomer is preferably 30% by mass or more based on the total amount of the resin composition. When the content is 30% by mass or more based on the total amount of the resin composition, the characteristics of the resin material can be exhibited, and the rolling resistance of the tire can be further reduced. Further, the content of the polyester-based thermoplastic elastomer is more preferably 50% by mass or more, and particularly preferably 70% by mass or more.

(Polyester thermoplastic elastomer)
`` Polyester thermoplastic elastomer '' is a polymer compound having elasticity, a polymer constituting a hard segment having a high melting point which is crystalline, and a polymer constituting a soft segment having an amorphous and low glass transition temperature, And a thermoplastic resin material comprising a polyester resin as a polymer constituting the hard segment. Examples of the polyester-based thermoplastic elastomer include an ester-based thermoplastic elastomer specified in JIS K6418: 2007.
The polyester-based thermoplastic elastomer in the present invention may have an amide bond.

  The polyester-based thermoplastic elastomer is not particularly limited, but it is common that the crystalline polyester forms the hard segment having a high melting point and the amorphous polymer forms the soft segment having a low glass transition temperature. Polymers.

As the crystalline polyester forming the hard segment, 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 forming the hard segment include polyethylene terephthalate, polybutylene terephthalate, polystyrene terephthalate, polyethylene naphthalate, polybutylene naphthalate, and the like, with polybutylene terephthalate being preferred.

  One suitable aromatic polyester that forms the hard segment includes polybutylene terephthalate derived from 1,4-butanediol and any one of terephthalic acid and dimethyl terephthalate. Furthermore, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, diphenyl-4,4′-dicarboxylic acid, diphenoxyethanedicarboxylic acid, 5-sulfoisophthalic acid, or these And a diol having a molecular weight of 300 or less (e.g., an aliphatic diol such as ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, and decamethylene glycol; Alicyclic diols such as 4-cyclohexanedimethanol and tricyclodecane dimethylol, xylylene glycol, bis (p-hydroxy) diphenyl, bis (p-hydroxyphenyl) propane, 2,2-bis [4- (2- Hydroxy Ethoxy) phenyl] propane, bis [4- (2-hydroxy) phenyl] sulfone, 1,1-bis [4- (2-hydroxyethoxy) phenyl] cyclohexane, 4,4′-dihydroxy-p-terphenyl, Or an aromatic diol such as 4,4'-dihydroxy-p-quarterphenyl], or a copolymerized polyester obtained by combining two or more of these dicarboxylic acid components and diol components. It is also possible to copolymerize a trifunctional or higher polyfunctional carboxylic acid component, a polyfunctional oxyacid component, a polyfunctional hydroxy component and the like in a range of 5 mol% or less.

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

  Among these aliphatic polyethers and aliphatic polyesters, poly (tetramethylene oxide) glycol, ethylene oxide adduct of poly (propylene oxide) glycol, poly (ε- Caprolactone), polybutylene adipate, polyethylene adipate and the like are preferred.

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

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

  When a polyester-based thermoplastic elastomer is used as the resin material, the content of the polyester-based thermoplastic elastomer is preferably 30% by mass or more based on the total amount of the resin composition. When the content is 30% by mass or more based on the total amount of the resin composition, the characteristics of the resin material can be exhibited, and the rolling resistance of the tire can be further reduced. Further, the content of the polyester-based thermoplastic elastomer is more preferably 50% by mass or more, and particularly preferably 70% by mass or more.

  When a mixture of a polyamide-based thermoplastic elastomer and a polyester-based thermoplastic elastomer is used as the specific resin material, the mass ratio (x) between the polyamide-based thermoplastic elastomer (x) and the polyester-based thermoplastic elastomer (y) is used. : Y) is preferably from 95: 5 to 50:50. When the mass ratio of these elastomers is 95: 5 to 50:50, the polyamide-based thermoplastic elastomer and the polyester-based thermoplastic elastomer maintain the properties of the polyamide-based thermoplastic elastomer while maintaining the properties of the polyester-based thermoplastic elastomer. Properties can be imparted and the elastic modulus of the tire can be easily controlled while maintaining the weldability between the reinforcing cord member made of a polyamide-based thermoplastic elastomer and the tire frame, thereby further improving the tire durability. However, it is possible to provide a tire that is less likely to be deformed by temperature changes. The mass ratio (x: y) of the polyamide-based thermoplastic elastomer (x) to the polyester-based thermoplastic elastomer (y) is more preferably 90:10 to 50:50.

  The specific resin material composition may be, if desired, a resin other than the above (including a thermoplastic elastomer), a rubber, various fillers (eg, silica, calcium carbonate, clay), an antioxidant, an oil, a plasticizer, a coloring agent. Various additives such as an agent, a weathering agent and a reinforcing material may be contained. The content of the additive in the resin composition (tire skeleton) is not particularly limited, and may be appropriately used as long as the effects of the present invention are not impaired.

(Carbodiimide compound)
The resin composition of the present invention contains a carbodiimide compound. The carbodiimide compound may be any compound having at least one carbodiimide group in the molecule, such as N, N'-diisopropylcarbodiimide, N, N'-di (o-toluyl) carbodiimide, N, N Monofunctional carbodiimide compounds such as' -dicyclohexylcarbodiimide, N, N'-bis (2,6-diisopropylphenyl) carbodiimide; p-phenylene-bis (2,6-xylylcarbodiimide), p-phenylene-bis (t- Butyl carbodiimide), bifunctional carbodiimide compounds such as p-phenylene-bis (mesityl carbodiimide), tetramethylene-bis (t-butyl carbodiimide), cyclohexane-1,4-bis (methylene-t-butyl carbodiimide); Multi-level officials such as condensates of monomers Functional carbodiimide compounds and the like, and among them, a polyfunctional carbodiimide compound is preferable. Here, the polyfunctional carbodiimide compound refers to a compound having two or more carbodiimide groups. Examples of the polyfunctional carbodiimide compound include carbodilite LA-1 (manufactured by Nisshinbo), carbodilite HMV-8CA (manufactured by Nisshinbo), carbodilite HMV-15CA (manufactured by Nisshinbo), elast stub H01 (manufactured by Nisshinbo), Stabaxol P And polyfunctional carbodiimide compounds generally known by trade names such as (RheinChemie). One or more of these carbodiimide compounds can be used.

  In the resin composition of the present invention, the content ratio of the (B) carbodiimide compound to the specific resin material when (A) the specific resin material is 100 parts by mass is from 0.3 parts by mass to 6 parts by mass. Including in the range of less than. When the carbodiimide compound is contained in this range, an increase in tan δ of the resin composition when exposed to wet heat conditions can be suppressed, or the tan δ can be reduced as compared to before exposure to wet heat conditions. . Furthermore, even in a tire containing the resin composition, the rolling resistance of the tire after being exposed to wet heat conditions can be further reduced. Further, the carbodiimide compound is more preferably contained in a content of 0.5 parts by mass to 5.5 parts by mass with respect to the specific resin material, and preferably contained in a content ratio of 1.0 parts by mass to 0.55 parts by mass. Is particularly preferred, and most preferably contained in a content ratio of 2.0 parts by mass to 5.5 parts by mass.

  Further, after being exposed to wet heat conditions, the specific resin material forming the tire skeleton or the like may include a resin that has changed to a structure derived from a carbodiimide compound.

(Physical properties of resin composition)
Next, preferable physical properties of the resin composition constituting the tire frame will be described. The resin composition of the present invention uses the above-mentioned specific resin material and carbodiimide compound.

The tan δ of the resin composition (tire frame body) itself is appropriately adjusted depending on the type and the mixing ratio of the specific resin material and the content of the carbodiimide compound, but the rolling resistance of the tire after being exposed to wet heat conditions. From the viewpoint of further reducing the tan δ, the maximum tan δ at 30 ° C before the resin composition (tire frame) is exposed to wet heat conditions is preferably more than 0 and less than 0.06. Further, tan δ is more preferably 0.02 to 0.055, and particularly preferably 0.025 to 0.05.
The tan δ of the resin composition (tire skeleton) itself was measured at 30 ° C. using a commercially available viscoelasticity measuring tester after preparing a No. 5 dumbbell-shaped test piece specified in JIS K6251 (1993). It can be obtained by measuring at a distortion of 1% and a frequency of 20 Hz.

In addition, the melting point (or softening point) of the resin composition itself is usually 100 ° C. to 350 ° C., and preferably about 100 ° C. to 250 ° C., but from the viewpoint of tire productivity, about 120 ° C. to 250 ° C. Preferably, the temperature is from 120C to 200C.
As described above, by using the resin composition having a melting point of 120 ° C. to 250 ° C., for example, when a tire frame is formed by fusing the divided bodies (frame pieces), the peripheral temperature of 120 ° C. to 250 ° C. Even if the skeleton is fused in the temperature range, the adhesive strength between the tire skeleton pieces is sufficient. Therefore, the tire of the present invention has excellent running durability such as puncture resistance and wear resistance. The heating temperature is preferably 10 ° C to 150 ° C higher than the melting point (or softening point) of the resin composition forming the tire skeleton piece, and more preferably 10 ° C to 100 ° C.

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

  The tensile yield strength defined by JIS K7113 (1995) of the resin composition itself is preferably 5 MPa or more, more preferably 5 MPa to 20 MPa, and even more preferably 5 MPa to 17 MPa. When the tensile yield strength of the resin composition is 5 MPa or more, the resin composition can withstand deformation due to a load applied to the tire during running or the like.

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

  The tensile elongation at break specified in JIS K7113 (1995) of the resin composition itself is preferably 50% or more, more preferably 100% or more, further preferably 150% or more, and particularly preferably 200% or more. When the tensile elongation at break of the resin composition is 50% or more, the rim assemblability is good, and the resin composition can be hardly broken by collision.

  The deflection temperature under load (at a load of 0.45 MPa) defined by ISO75-2 or ASTM D648 of the resin composition itself is preferably 50 ° C or higher, more preferably 50 ° C to 150 ° C, and further preferably 50 ° C to 130 ° C. preferable. When the deflection temperature under load of the resin composition is 50 ° C. or more, the deformation of the tire frame can be suppressed even when vulcanization is performed in the production of the tire.

(Reinforcing cord member)
The tire of the present invention may further include a reinforcing cord member wound around the outer periphery of the tire frame in the circumferential direction to form a reinforcing cord layer, and the reinforcing cord member may be coated with a coating resin. .
Here, the coating resin is a concept including a thermoplastic resin and a thermosetting resin, and may include any resin as long as the effects of the present invention are not impaired. Does not include rubber.
As described above, when the coating resin is contained in the reinforcing cord layer, the reinforcing cord member can be further adhered and fixed to the tire frame.

  Furthermore, when the reinforcing cord member is a metal cord such as a steel cord, when the tire is disposed of, the reinforcing cord member is separated from the cushion rubber, whereas the vulcanized rubber is difficult to separate from the reinforcing cord member only by heating, The coating resin can be separated from the reinforcing cord member only by heating. This is advantageous in terms of tire recyclability. Further, the coating resin usually has a lower loss coefficient (tan δ) than vulcanized rubber. Therefore, when the reinforcing cord layer contains a large amount of the coating resin, the rolling properties of the tire can be improved. Further, a resin having a relatively high elastic modulus as compared with the vulcanized rubber has an advantage that it has a large in-plane shear rigidity and is excellent in handling and abrasion resistance during tire running.

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

  Examples of the thermoplastic resin that can be used for the reinforcing cord layer include urethane resins, olefin resins, vinyl chloride resins, polyamide resins, polyester resins, and the like.

  Examples of the thermoplastic elastomer for the coating resin include amide-based thermoplastic elastomers (TPA), ester-based thermoplastic elastomers (TPC), olefin-based thermoplastic elastomers (TPO), and styrene-based thermoplastic elastomers defined in JIS K6418: 2007. Examples include thermoplastic elastomer (TPS), urethane-based thermoplastic elastomer (TPU), crosslinked thermoplastic rubber (TPV), and other thermoplastic elastomers (TPZ). It is preferable to use a thermoplastic elastomer in consideration of the elasticity required during running and the moldability during manufacturing.

When the reinforcing cord member is covered with the covering resin as described above, the covering resin is preferably the specific resin material in the present invention. In this case, since the reinforcing cord layer and the tire frame are made of the same resin, the adhesion between the reinforcing cord layer and the tire frame can be further improved.
Furthermore, it is particularly preferable that the coating resin covering the reinforcing cord member is the specific resin and the carbodiimide compound, that is, the resin composition of the present invention. In this case, since the adhesion between the reinforcing cord layer and the tire skeleton can be further improved, as a result, while improving tan δ in the coating resin, migration of the carbodiimide compound from the tire skeleton to the coating resin can be prevented. Since it can be suppressed, the effect of the present invention is not easily impaired.
Further, the amount of the carbodiimide compound contained in the coating resin is more preferably 0.5 to 5.5 parts by mass based on the specific resin material, similarly to the resin composition of the tire skeleton. , 1.0 parts by mass to 0.55 parts by mass, and most preferably 2.0 parts by mass to 5.5 parts by mass.
By setting the content in this range, not only can effectively prevent the improvement of tan δ in the coating resin, but also the migration of the carbodiimide compound from the tire frame to the coating resin can be further suppressed, and the reinforcing cord Adhesion between the member and the coating resin can be ensured.
Further, the coating resin that covers the reinforcing cord member may directly cover the surface of the reinforcing cord member, or another layer may be provided between the reinforcing cord member and the coating resin. .

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 resin composition forming the tire frame. It is preferable to set When the modulus of elasticity of the resin material is 10 times or less of the modulus of elasticity of the resin composition forming the tire skeleton, the crown portion is not too hard and the rim assembling property is easy. Further, when the elastic modulus of the resin material is 0.1 times or more the elastic modulus of the resin composition forming the tire frame, the resin constituting the reinforcing cord layer is not too soft, and the in-plane shear rigidity is reduced. Excellent cornering power is improved.
When a resin material is included in the reinforcing cord layer, the reinforcing cord member is covered with the resin material in an area of 20% or more of the surface from the viewpoint of enhancing the pullability (hardness of pulling out) of the reinforcing cord. Preferably, 50% or more of the area is covered. Further, the content of the resin material in the reinforcing cord layer is preferably 20% by mass or more with respect to the total amount of the materials constituting the reinforcing cord layer excluding the reinforcing cord, from the viewpoint of enhancing the pullability of the reinforcing cord, 50 mass% or more is more preferable.

[First Embodiment]
Hereinafter, a tire according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1A is a perspective view showing a partial cross section of a tire according to the first embodiment of the present invention. FIG. 1B is a sectional view of a bead portion mounted on a rim. As shown in FIG. 1, the tire 10 of the present embodiment has a cross section 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 come into contact with a bead sheet 21 and a rim flange 22 of a rim 20 shown in FIG. And a crown portion 16 (outer peripheral portion) connecting a radially outer end of one side portion 14 and a radially outer end of the other side portion 14 to each other. ing.

  Here, the tire case 17 of the present embodiment includes, as a resin composition, for example, a resin material containing at least one of an amide bond and an ester bond, and a carbodiimide compound, and the carbodiimide compound with respect to 100 parts by mass of the resin material. Formed from a resin composition having a content of 0.3 parts by mass or more and less than 6 parts by mass.

  In the present embodiment, the tire case 17 is formed of the above-described components. However, the present invention is not limited to this configuration. Other resin materials having different characteristics may be used for the side part 14, the crown part 16, the bead part 12, and the like. A reinforcing material (a polymer material, a metal fiber, a cord, a nonwoven fabric, a woven fabric, or the like) is buried and arranged in the tire case 17 (for example, the bead portion 12, the side portion 14, the crown portion 16, and the like). 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 resin composition. The tire case half 17A is formed by integrally forming one bead portion 12, one side portion 14, and a half-width crown portion 16 by injection molding or the like, and facing each other to form an annular shaped tire case half 17A. It is formed by joining at the tire equatorial plane. Note that the tire case 17 is not limited to being formed by joining two members, and may be formed by joining three or more members.

The tire case half 17A formed of the resin composition can be formed by, for example, vacuum forming, pressure forming, injection molding, melt casting, or the like. For this reason, compared with the case where a tire case is molded with rubber as in the conventional case, there is no need to perform vulcanization, the manufacturing process can be greatly simplified, and the molding time can be reduced.
In the present embodiment, the tire case half 17A has a symmetrical shape, that is, the one tire case half 17A and the other tire case half 17A have the same shape. There is also an advantage that only one type of die is required.

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

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

  As shown in FIG. 1, a reinforcing cord 26 having higher rigidity than the specific resin material forming 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 spirally wound in a state where 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, and forms a reinforcing cord layer 28. On the outer peripheral side in the tire radial direction of the reinforcing cord layer 28, a crown 30 made of a material having more excellent wear resistance than the specific resin material constituting the tire case 17, for example, rubber is arranged.

  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 a tire rotation axis showing a state in which a reinforcing cord is embedded in a crown portion of a tire case of the tire of the first embodiment. As shown in FIG. 2, the reinforcing cord 26 is spirally wound with at least a part embedded in the crown portion 16 in a cross-sectional view along the axial direction of the tire case 17. A reinforcing cord layer 28 indicated by a broken line in FIG. The portion of the reinforcing cord 26 embedded in the crown 16 is in close contact with the resin composition constituting the crown 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 obtained by twisting steel fibers can be used. In this embodiment, a steel cord is used as the reinforcing cord 26.

  In FIG. 2, the embedding amount L indicates the embedding 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 with respect to the crown portion 16 is preferably at least 1/5 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 embedding amount L of the reinforcing cord 26 exceeds の of the diameter D of the reinforcing cord 26, it is difficult for the reinforcing cord 26 to protrude from the embedded portion due to the dimensions 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 in which the reinforcing cord 26 is embedded, the reinforcing cord 26 is located around the reinforcing cord. The entry of air can be suppressed. The reinforcing cord layer 28 corresponds to a belt disposed on the outer peripheral surface of a carcass of a conventional rubber pneumatic tire.

As described above, the crown 30 is disposed on the outer peripheral side of the reinforcing cord layer 28 in the tire radial direction. As the rubber used for the crown 30, it is preferable to use the same type of rubber as that used for a conventional rubber pneumatic tire. Instead of the crown 30, a crown formed of another type of resin material having more excellent wear resistance than the specific resin material forming the tire case 17 may be used. Further, the crown 30 is formed with a crown pattern including a plurality of grooves on a ground contact surface with a road surface, similarly to a conventional rubber pneumatic tire.
Hereinafter, a method for manufacturing the tire of the present embodiment will be described.

(Tire case molding process)
First, a resin material containing at least one of an amide bond and an ester bond as described above, and a carbodiimide compound, wherein the content of the carbodiimide compound is 0.3 parts by mass or more and 6 parts by mass with respect to 100 parts by mass of the resin material. A tire case half is formed by using a resin composition that is less than. These tire cases are preferably formed by injection molding. Next, the tire case halves supported by the thin metal support ring face each other. Next, a joining mold (not shown) is set so as to be in contact with the outer peripheral surface of the butted portion of the tire case half. Here, the joining mold is configured to press the periphery of the joining portion (butting portion) of the tire case half 17A with a predetermined pressure. Next, the periphery of the joint portion of the tire case half is pressed at a temperature equal to or higher than the melting point (or softening point) of the resin composition constituting the tire case. When the joining portion of the tire case half is heated and pressurized by a joining mold, the joining portion is melted, the tire case halves are fused, and these members are integrated to form the tire case 17. 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. Alternatively, the tire case halves may be joined by being softened or melted in advance by hot air, infrared irradiation, or the like, and then pressed by a joining mold.

(Reinforcing cord member winding process)
Next, the reinforcing cord winding step 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 is provided with a reel 58 around which the reinforcing cord 26 is wound, a cord heating device 59 disposed on the downstream side of the reel 58 in the cord conveying direction, and a downstream side of the reinforcing cord 26 in the conveying direction. A first roller 60, a first cylinder device 62 that moves the first roller 60 in a direction to contact and separate from the tire outer peripheral surface, and a first roller 60 disposed downstream of the reinforcing cord 26 in the transport direction of the first roller 60. And a second cylinder device 66 that moves the second roller 64 in a direction of moving toward and away from the tire outer peripheral surface. The second roller 64 can be used as a metal cooling roller. 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 the adhesion of the melted or softened resin composition. Coated with. In the present embodiment, the code supply device 56 has a configuration including two rollers, the first roller 60 and the second roller 64, but the present invention is not limited to this configuration, and any one of the rollers may be used. Only one roller (that is, one roller) may be used.

  Further, the cord heating device 59 includes a heater 70 and a fan 72 that generate hot air. In addition, the cord heating device 59 includes a heating box 74 through which the reinforcing cord 26 passes, through which hot air is supplied, and an outlet 76 for discharging the heated reinforcing cord 26.

  In this step, first, the temperature of the heater 70 of the cord heating device 59 is increased, and the surrounding 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 whose internal space is heated by hot air and heated (for example, the temperature of the reinforcing cord 26 is heated to about 100 to 200 ° C.). The heated reinforcing cord 26 is spirally wound with a certain tension 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 resin composition at the contact portion is melted or softened, and at least a part of the heated reinforcing cord 26 becomes on the outer peripheral surface of the crown portion 16. Buried. At this time, since the heated reinforcing cord 26 is embedded in the molten or softened resin composition, the resin composition and the reinforcing cord 26 have no gap, that is, are in close contact with each other. This suppresses air from entering the portion where the reinforcing cord 26 is embedded. In addition, by heating the reinforcing cord 26 to a temperature higher than the melting point (or softening point) of the resin composition of the tire case 17, melting or softening of the resin composition in a portion where the reinforcing cord 26 is in contact is promoted. This makes it easier to embed the reinforcing cord 26 in the outer peripheral surface of the crown portion 16 and effectively suppresses air entry.

  The embedding amount L of the reinforcing cord 26 can be adjusted by the heating temperature of the reinforcing cord 26, the tension acting on the reinforcing cord 26, the pressing force of the first roller 60, and the like. In this embodiment, the embedding amount L of the reinforcing cord 26 is set to be equal to or more than １ ／ of the diameter D of the reinforcing cord 26. It is more preferable that the embedding amount L of the reinforcing cord 26 exceeds 1/2 of the diameter D, and it is most preferable that the entire reinforcing cord 26 is embedded.

  In this way, the heated reinforcement cord 26 is wound while being buried in the outer peripheral surface of the crown portion 16, thereby forming the reinforcement cord layer 28 on the outer peripheral side of the crown portion 16 of the tire case 17.

  Next, the vulcanized belt-shaped crown 30 is wound around the outer circumferential surface of the tire case 17 for one round, and the crown 30 is bonded to the outer circumferential surface of the tire case 17 using an adhesive or the like. The crown 30 may be, for example, a pre-cured crown used for a conventionally known retreaded tire. This step is the same as the step of bonding the pre-cured crown to the outer peripheral surface of the base tire of the retreaded tire.

  Then, the tire 10 is completed by bonding a seal layer 24 made of vulcanized rubber to the bead portion 12 of the tire case 17 using an adhesive or the like.

(Action)
In the tire 10 of the present embodiment, since the tire case 17 is formed of a resin composition containing a polyamide-based thermoplastic elastomer having an ester bond and a carbodiimide compound, the rolling resistance of the tire after being exposed to wet heat conditions Increase can be suppressed. Further, the weight of the tire 10 is light because the structure is simpler than that of a conventional rubber tire. Therefore, the tire 10 of the present embodiment has high friction resistance and durability. Further, since the tire case 17 can be injection-molded, the productivity is very excellent.

  In the tire 10 of the present embodiment, a reinforcing cord 26 having higher rigidity than the resin composition is spirally wound around the outer peripheral surface of the crown portion 16 of the tire case 17 formed of the resin composition. As a result, the puncture resistance, the cut resistance, and the circumferential rigidity of the tire 10 are improved. In addition, the creep of the tire case 17 formed of the resin composition is prevented by improving the circumferential rigidity of the tire 10.

  Also, in a cross-sectional view along the axial direction of the tire case 17 (cross-section shown in FIG. 1), at least a part of the reinforcing cord 26 is embedded in the outer peripheral surface of the crown portion 16 of the tire case 17 formed of the resin composition. In addition, since it is in close contact with the resin composition, air entry during manufacturing is suppressed, and the movement of the reinforcing cord 26 due to input during traveling or the like is suppressed. Thereby, the occurrence of peeling or the like on the reinforcing cord 26, the tire case 17, and the crown 30 is suppressed, and the durability of the tire 10 is improved.

When the reinforcing cord layer 28 is configured to include a resin, the difference in hardness between the tire case 17 and the reinforcing cord layer 28 can be reduced as compared with the case where the reinforcing cord 26 is fixed with cushion rubber. The reinforcing cord 26 can be closely attached and fixed to the tire case 17. Accordingly, the above-described air entry can be effectively prevented, and the movement of the reinforcing cord member during traveling can be effectively suppressed.
Further, when the reinforcing cord 26 is a steel cord, the reinforcing cord 26 can be easily separated and collected from the resin by heating at the time of disposal of the tire, which is advantageous in terms of recyclability of the tire 10. Further, since the resin has a lower loss coefficient (tan δ) than the vulcanized rubber, if the reinforcing cord layer 28 contains a large amount of the resin, the rolling property of the tire can be improved. Further, the resin has the advantage that the in-plane shear rigidity is larger than the vulcanized rubber, and the handleability and abrasion resistance during tire running are excellent.

  Further, as shown in FIG. 2, since the embedded amount L of the reinforcing cord 26 is equal to or more than ５ of the diameter D, air intrusion at the time of manufacturing is effectively suppressed. Accordingly, the movement of the reinforcing cord 26 is further suppressed.

In addition, since the crown 30 that comes into contact with the road surface is made of a rubber material that is more wear-resistant than the resin composition that forms the tire case 17, 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 firmly attached to the rim 20, similarly to a conventional rubber pneumatic tire. Is held.

  Since the tire case 17 uses a polyamide-based thermoplastic elastomer containing an ester bond, a portion of the bead portion 12 that comes into contact with the rim 20 is made of a rubber material having a more sealing property than the specific resin material forming the tire case 17. By providing the sealing layer 24, the rim assembly between the tire 10 and the rim 20 can be further improved.

  In the above-described embodiment, the reinforcing cord 26 is heated, and the surface of the tire case 17 at the portion where the heated reinforcing cord 26 contacts is melted or softened. However, the present invention is not limited to this configuration. After heating the outer peripheral surface of the crown portion 16 in which the reinforcing cord 26 is embedded by using a hot air generator without heating the reinforcing cord 26, the reinforcing cord 26 may be embedded 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 may be directly heated by radiant heat (for example, infrared rays). Good.

  Furthermore, in the first embodiment, the portion where the resin composition in which the reinforcing cord 26 is embedded is melted or softened is forcibly cooled by the second metal roller 64, but the present invention is limited to this configuration. Alternatively, a configuration may be employed in which cold air is directly blown to the portion where the resin composition has melted or softened, and the molten or softened portion of the resin composition is forcibly cooled and solidified.

  Further, in the first embodiment, the reinforcing cord 26 is heated. However, for example, the outer circumference of the reinforcing cord 26 may be covered with the same resin composition as the tire case 17. When the cord is wound around the crown portion 16 of the tire case 17, the resin composition coated with the reinforcing cord 26 is also heated, so that air entry during embedding in the crown portion 16 can be effectively suppressed.

  In addition, although it is easy to manufacture the reinforcing cord 26 in a spiral manner in manufacturing, a method of discontinuing the reinforcing cord 26 in the width direction may be considered.

  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 mounting the bead portion 12 on the rim 20, but the present invention is not limited to this configuration. Instead, it may be a complete tube shape. Further, the tire of the present invention is an embodiment using a reinforcing cord member in which the cord member is covered with a resin material as shown in a second embodiment (FIGS. 4 and 5) of JP-A-2012-46030. Is also good.

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various changes can be made without departing from the scope of the invention. Needless to say, the scope of rights 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 of the present embodiment has substantially the same cross-sectional shape as a conventional general rubber pneumatic tire. For this reason, in the following drawings, the same components as those in the first embodiment are denoted by the same reference numerals. FIG. 4A is a cross-sectional view along the tire width direction of the tire of the second embodiment, and FIG. 4B is a tire of a bead portion in a state where a rim is fitted to the tire of the second embodiment. It is an enlarged view of the section along the width direction. FIG. 5 is a cross-sectional view along the tire width direction showing the periphery of the reinforcing layer of the tire according to the second embodiment.

  In the tire according to the second embodiment, the tire case 17 includes a resin material containing at least one of an amide bond and an ester bond and a carbodiimide compound, as in the first embodiment described above, and 100 parts by mass of the resin material. The carbodiimide compound is formed from a resin composition having a content of 0.3 parts by mass or more and less than 6 parts by mass with respect to the resin composition. In this embodiment, as shown in FIGS. 4 and 5, the tire 200 has a reinforcing cord layer 28 (indicated by a broken line in FIG. 5) in which the covering cord member 26 </ b> B is wound around the crown 16 in the circumferential direction. Are stacked). The reinforcing cord layer 28 forms 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 coating cord member 26B is a resin for coating separately from the resin composition forming the tire case 17 on the cord member 26A having higher rigidity than the specific resin material in the resin composition forming the tire case 17. It is formed by coating the coating resin 27. In addition, the coating cord member 26B and the crown portion 16 are joined (for example, welded or bonded with an adhesive) at a contact portion with the crown portion 16.
Further, as the coating resin 27, the same composition as the resin composition forming the tire case 17 may be used, or the same resin material as the specific resin material in the resin composition may be used.

  Further, it is preferable that the elastic modulus of the coating resin 27 be set in a range of 0.1 to 10 times the elastic modulus of the resin composition forming the tire case 17. When the elastic modulus of the coating resin 27 is 10 times or less the elastic modulus of the resin composition forming the tire case 17, the crown portion is not too hard and the rim assembling property is easy. When the elastic modulus of the coating resin 27 is 0.1 times or more of the elastic modulus of the tire case 17, the resin constituting the reinforcing cord layer 28 is not too soft and has excellent in-plane shear rigidity. Cornering power is improved.

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

  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 adjacent covering cord members 26B. For this reason, the outer peripheral surface of the reinforcing cord layer 28 is made 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.

  Fine roughening unevenness 96 is uniformly formed on the outer peripheral surface 17S (including the unevenness) of the tire case 17, and the cushion rubber 29 is bonded thereon via a bonding agent. The rubber portion of the cushion rubber 29 on the radially inner side flows into the roughened unevenness 96.

  On the cushion rubber 29 (outer peripheral surface), a tread 30 made of a material having more excellent wear resistance than the specific resin material in the resin composition forming the tire case 17, for example, rubber is joined. .

  The rubber used for the tread 30 (tread rubber 30A) 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 resin material having more excellent wear resistance than the specific resin material forming the tire case 17 may be used. The tread 30 has a tread pattern (not shown) including a plurality of grooves on a ground contact surface with a road surface, similarly to a conventional rubber pneumatic tire.

Next, a method for manufacturing the tire of the present embodiment will be described.
(Tire frame formation step)
(1) First, a tire case half 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 a tire case 17.

(Reinforcing cord member winding process)
(2) The tire manufacturing apparatus according to the present embodiment is the same as the above-described first embodiment. In the cord supply device 56 shown in FIG. 3 of the above-described first embodiment, the reel 58 is coated with the cord member 26A. What wound around the covering cord member 26B which cross section shape covered with resin 27 (in this embodiment, a thermoplastic material) is substantially trapezoidal is used.

  First, the temperature of the heater 70 is increased, and the surrounding 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 a heating box 74 whose internal space is heated by hot air and heated (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 27). I do. Here, the coating resin 26B is melted or softened by heating the coating cord member 26B.

  Then, the covering cord member 26B is spirally wound with a certain tension on the outer peripheral surface of the crown portion 16 of the tire case 17 rotating in the front direction of the drawing through the outlet 76. At this time, the lower surface 26D of the covering cord member 26B comes into contact with the outer peripheral surface of the crown portion 16. Then, the coating resin 27 in the melted or softened state at the contacted portion spreads on the outer peripheral surface of the crown 16, and the coating cord member 26 </ b> B is welded to the outer peripheral surface of the crown 16. Thereby, the joining strength between the crown portion 16 and the covering cord member 26B is improved.

(Roughening treatment step)
(3) Next, by using a blast device (not shown), the shot material is injected at a high speed toward the outer peripheral surface 17S while rotating the tire case 17 side toward the outer peripheral surface 17S of the tire case 17. The injected blast material collides with the outer peripheral surface 17S, and forms fine roughened irregularities 96 having an arithmetic average roughness Ra of 0.05 mm or more on the outer peripheral surface 17S.
In this way, by forming the fine roughened unevenness 96 on the outer peripheral surface 17S of the tire case 17, the outer peripheral surface 17S becomes hydrophilic, and the wettability of a bonding agent described later is improved.

(Lamination process)
(4) Next, a bonding agent is applied to the outer peripheral surface 17S of the roughened tire case 17.
In addition, as a bonding agent, a rubber-based adhesive such as a halogenated rubber-based adhesive (for example, a chlorinated rubber-based adhesive), a triazine thiol-based adhesive, a phenol-based resin adhesive, an isocyanate-based adhesive, and the like are not particularly limited. However, it is preferable to react at a temperature (90 ° C. to 140 ° C.) at which the cushion rubber 29 can be vulcanized.

(5) Next, an unvulcanized cushion rubber 29 is wrapped 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. One turn of the vulcanized or semi-vulcanized tread rubber 30A is wound therearound to obtain a green tire case state.

(Vulcanization process)
(6) Next, the green tire case is accommodated in a vulcanized can or a mold and vulcanized. At this time, the unvulcanized cushion rubber 29 flows into the roughened unevenness 96 formed on the outer peripheral surface 17S of the tire case 17 by the roughening process. When the vulcanization is completed, the cushion rubber 29 flowing into the roughening unevenness 96 exerts an anchor effect, 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.

(8) Then, the seal layer 24 made of a soft material that is softer than the resin material is adhered to the bead portion 12 of the tire case 17 using an adhesive or the like, whereby the tire 200 is completed.

(Action)
In the tire 200 of the present embodiment, the tire case 17 includes a resin material containing at least one of an amide bond and an ester bond, and a carbodiimide compound, and the content of the carbodiimide compound is 0.3 with respect to 100 parts by mass of the resin material. Since the resin composition is not less than 6 parts by mass and less than 6 parts by mass, it is possible to suppress and further reduce the increase in rolling resistance of the tire after being exposed to wet heat conditions. Furthermore, since the tire structure can be simplified, the weight is lighter than conventional rubber. For this reason, the tire 200 of this embodiment has excellent durability, is hardly affected by temperature changes, and has good fuel efficiency when used in an automobile.

  Further, when the reinforcing cord layer 28 is configured to include the covering cord member 26B, the hardness of the tire case 17 and the reinforcing cord layer 28 is smaller than when the reinforcing cord 26A is simply fixed with the cushion rubber 29. Since the difference can be reduced, the covering cord member 26B can be further closely attached to and fixed to the tire case 17. Accordingly, the above-described air entry can be effectively prevented, and the movement of the reinforcing cord member during traveling can be effectively suppressed.

Further, when the reinforcing cord is a steel cord, the cord member 26A can be easily separated and collected from the covered cord member 26B by heating at the time of disposal of the tire, which is advantageous in terms of recyclability of the tire 200. Further, the resin material usually has a lower loss coefficient (tan δ) than vulcanized rubber. Therefore, when the reinforcing cord layer contains a large amount of resin, the rolling properties of the tire can be improved. Further, a resin having a relatively high elastic modulus as compared with the vulcanized rubber has an advantage that it has a large in-plane shear rigidity and is excellent in handling and abrasion resistance during tire running.
Further, as the coating resin 27 for coating the reinforcing cord member 26A, a composition similar to the resin composition forming the tire case 17 may be used. Thereby, tan δ of the reinforcing cord member 26B can be further reduced, and further, an increase in the rolling resistance of the tire can be suppressed.

  In the tire manufacturing method of the present embodiment, when the tire case 17 is integrated with the cushion rubber 29 and the tread rubber 30A, the outer peripheral surface 17S of the tire case 17 is subjected to a roughening treatment. (Adhesiveness) is improved. Further, since the resin composition forming the tire case 17 is dug up by the collision of the shot material, the wettability of the bonding agent is improved. Thereby, the bonding agent is held in a uniform application 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 secured.

  In particular, even if the outer peripheral surface 17S of the tire case 17 has irregularities, the projection material collides with the concave portion (gap 28A) to roughen the periphery of the concave portion (concave wall, concave bottom), and the tire case 17 The bonding strength between the cushion rubber 29 and the cushion rubber 29 can be secured.

  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 secured.

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

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

  Also, since the outer peripheral portion of the tire case 17 is constituted by the reinforcing cord layer 28, puncture resistance and cut resistance are improved as compared with the case where the outer peripheral portion is constituted by something other than the reinforcing cord layer 28. I 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, the creep of the tire case 17 (a phenomenon in which the plastic deformation of the tire case 17 increases with time under a constant stress) is suppressed, and the pressure resistance to the air pressure from the tire radial inside is reduced. improves.

In the present embodiment, irregularities are formed on the outer peripheral surface 17S of the tire case 17, but the present invention is not limited to this, and the outer peripheral surface 17S may be formed flat.
In the tire case 17, the reinforcing cord layer may be formed so that the covering cord member wound around and joined to the crown portion of the tire case is covered with the covering thermoplastic material. In this case, the coating thermoplastic layer in a molten or softened state can be discharged onto the reinforcing cord layer 28 to form a coating layer. Instead of using an extruder, the covering sheet may be formed by heating the welded sheet to a molten or softened state and pasting it on the surface (outer peripheral surface) of the reinforcing cord layer 28.

  In the above-described second embodiment, the case divided body (tire case half 17A) is joined to form the tire case 17, but the present invention is not limited to this structure, and the tire case is formed using a mold or the like. 17 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 mounting the bead portion 12 on the rim 20, but the present invention is not limited to this configuration. Instead, the tire 200 may be, for example, a complete tube shape.

  In the second embodiment, the cushion rubber 29 is arranged 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 arranged.

  Further, in the second embodiment, the covering cord member 26B is spirally wound around the crown portion 16, but the present invention is not limited to this, and the covering cord member 26B is discontinuous in the width direction. It may be configured to be wound.

In the second embodiment, the coating resin 27 for forming the coating cord member 26B is made of a thermoplastic material, and the coating resin 27 is heated or melted or softened by heating, so that the coating cord member 26B is formed on the outer peripheral surface of the crown portion 16. However, the present invention is not limited to this configuration, and the coating cord member 26B may be bonded to the outer peripheral surface of the crown portion 16 using an adhesive or the like without heating the coating resin 27. Good.
Alternatively, the coating resin 27 forming the coating cord member 26B may be a thermosetting resin, and the coating cord member 26B may be bonded to the outer peripheral surface of the crown portion 16 using an adhesive or the like without heating.
Further, the coating resin 27 forming the coating cord member 26B may be a thermosetting resin, and the tire case 17 may be formed of a thermoplastic resin material. In this case, the covering cord member 26B may be adhered 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 melt or soften. In this state, the coated cord member 26B may be welded to the outer peripheral surface of the crown portion 16.
Further, the coating resin 27 forming the coating cord member 26B may be formed of a thermoplastic material, and the tire case 17 may be formed of a thermoplastic resin material. In this case, the covering cord member 26B may be adhered 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 melt or soften. The coating cord member 26B may be welded to the outer peripheral surface of the crown portion 16 while the coating resin 27 is heated to a molten or softened state while being in the state. When both the tire case 17 and the covering cord member 26B are heated to be in a molten or softened state, the two are well mixed and the joining strength is improved. When the resin material (specific resin material) forming the tire case 17 and the coating resin 27 forming the coating cord member 26B are both thermoplastic resin materials, the same type of thermoplastic material, particularly the same thermoplastic resin, is used. Preferably, it is a plastic material. Further, the same kind of resin material refers to a form such as ester-based or amide-based.

  Further, on the outer peripheral surface 17S of the roughened tire case 17, the surface of the outer peripheral surface 17S is activated by using a corona treatment, a plasma treatment, or the like, and after increasing the hydrophilicity, an adhesive is applied. Is also good.

Furthermore, the order for manufacturing the tire 200 is not limited to the order of the second embodiment, and may be appropriately changed.
The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various changes can be made without departing from the scope of the invention. Needless to say, the scope of rights of the present invention is not limited to these embodiments.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to this.
First, according to the above-described second embodiment, sample pieces and tires of tire cases (tire frame bodies) of Examples and Comparative Examples were produced. At this time, the materials shown in Table 1 below were used as materials for forming the sample pieces of the tire case. Further, in the production of the tire in each of the examples and comparative examples, after preparing a tire case with the same composition as the resin composition used for producing the sample piece of the tire case of each example and the comparative example, the following table A tire was produced using the reinforcing cord member described in No. 2.

<Preparation of tire case specimen>
(Components to be blended in the resin composition)
1. Specific resin material As the specific resin material to be included in the resin composition, a commercially available polyamide-based thermoplastic elastomer (Pebax5533SP, manufactured by Arkema) was used as it was.

2. Carbodiimide compound As the carbodiimide compound to be included in the resin composition, a commercially available carbodiimide compound (Stabaxol P, manufactured by Rhein Chemie) was used as it was.

(Preparation of sample piece of tire case)
In the preparation of the sample pieces of the tire case used in Examples 1 and 2 , first, the specific resin material and the carbodiimide compound were mixed with the composition shown in Table 1, and a plastmill (LABOPLASTOMILL 50MR twin screw extruder, manufactured by Toyo Seiki Seisaku-sho, Ltd.) ) To prepare pellets. In Comparative Example 1, pellets were prepared in the same manner as in Examples 1 and 2 , using only the specific resin material. In addition, Table 1 shows the content of the carbodiimide compound with respect to the specific resin material in parts by mass based on 100 parts by mass of the specific resin material.
Next, using the prepared pellets as a molding material, using an electric heat press (manufactured by Kodaira Seisakusho), heating at 230 ° C. and 12 MPa for 5 minutes to perform a heat press, and a length of 80 mm, a width of 40 mm, A resin plate having a thickness of 2 mm was prepared. A dumbbell-shaped test piece (No. 5 test piece) specified in JIS K6251 (1993) was punched from the resin plate prepared above to prepare a test piece of a tire case for evaluation.

<Measurement of tan δ before and after wet heat treatment>
Using the viscoelasticity measurement tester (manufactured by Rheometrics), the loss tangent of the sample pieces of the tire cases used in Examples 1 and 2 and Comparative Example 1 was measured at a temperature of 30 ° C., a strain of 1%, and a frequency of 20 Hz. (Tan δ) was measured.
Thereafter, the tire case specimens of Examples 1 and 2 and Comparative Example 1 were allowed to stand for 1000 hours under moist heat conditions (in an atmosphere of 80 ° C. and a humidity of 95% RH) (after moist heat treatment), and then, after each moist heat treatment. The tan δ of the sample piece was measured by the same method as described above. Table 1 shows the difference between tan δ (initial value) before wet heat treatment, tan δ after wet heat treatment (after 1000 hours), and tan δ before and after wet heat treatment for each sample piece.

As shown in Table 1, in Examples 1 and 2 , tan δ of the resin composition (tire frame) after the wet heat treatment was recovered as compared with tan δ before the wet heat treatment. The tan δ of each of Examples 1 and 2 before the wet heat treatment was higher than that of Comparative Example 1 containing no carbodiimide compound, but was lower than that of Comparative Example 1 after the wet heat treatment .
From the above results, when the content of the carbodiimide compound contained in the resin composition (tire skeleton) with respect to the specific resin material is 0.3% by mass or more and less than 6% by mass, after the wet heat treatment, tan δ decreases the carbodiimide compound. It was shown to be significantly lower than when not included .

It was also measured for tanδ at each time of Examples 1 and 2, and the tire casing specimen smell of Comparative Example 1 Te, from the start of the wet heat treatment up to 1000 hours.
As a result, the tan δ value of the resin composition of Comparative Example 1 (tire frame) containing no carbodiimide compound continued to increase with the lapse of time of the wet heat treatment, but the resin compositions of Examples 1 and 2 containing the carbodiimide compound did not contain the carbodiimide compound. On the contrary, it was shown that the tan δ value of the resin composition of Comparative Example 1 was reduced with the lapse of time of the wet heat treatment.

  As described above, by including the specific resin material and the specific content of the carbodiimide compound in the resin composition forming the tire frame, even after the tire is exposed to wet heat conditions, the tan δ value of the tire frame. It was shown that the rolling performance of the tire can be improved.

10,200 tire 12 bead 16 crown (outer circumference)
18 Bead Core
Reference Signs List 20 rim 21 bead seat 22 rim flange 17 tire case (tire frame)
24 Seal layer (seal part)
26 Reinforcement cord (reinforcement cord member)
26A cord member (reinforcement cord member)
28 Reinforcement cord layer 30 Tread D Diameter of reinforcement cord (diameter of reinforcement cord member)
L Reinforcement cord burial amount (reinforcement cord member burial amount)

Claims (5)

  At least (A) a resin material having at least one of an amide bond and an ester bond, and (B) a carbodiimide compound, wherein the content of the carbodiimide compound is 0.3 parts by mass or more with respect to 100 parts by mass of the resin material. A tire having a tire skeleton formed of a resin composition that is less than parts by mass.   The tire according to claim 1, wherein the resin material contains at least one resin selected from a polyamide thermoplastic elastomer, a polyester thermoplastic elastomer, a polyamide resin, and a polyester resin. Further having a reinforcing cord member that forms a reinforcing cord layer by being wound in the circumferential direction around the outer peripheral portion of the tire frame body,
The tire according to claim 1, wherein the reinforcing cord member is covered with at least a covering resin.   The tire according to claim 3, wherein the coating resin is the resin material.   The tire according to claim 3, wherein the coating resin is the resin composition.