Rubber composition for tire and tire using same

Abstract

The present invention provides a bead apex / rubber composition for an inter-ply rubber layer and a rubber composition for a bead apex / inter-ply rubber layer that can improve separation resistance without reducing driving stability and handling responsiveness object tires. Rubber composition for a bead apex / interply rubber layer and a tire having a bead apex / interply rubber layer composed of the rubber composition, wherein the bead apex / interply rubber The rubber composition for the layer further contains (A) 1.5 to 2.9 parts by mass of sulfur with respect to 100 parts by mass of the diene rubber component, and (B) a compound selected from the group consisting of modified resorcinol resin, cresol resin and modified formazan. At least one kind of phenol resin, 1 to 4 parts by mass, (C) 0.7 to 3 parts by mass of a partial condensate of hexamethylolmelamine pentamethyl ether or a partial condensate of hexamethoxymethylolmelamine, (D) 5-30 parts by mass of silicon dioxide and 10-55 parts by mass of (E) carbon black having a nitrogen adsorption specific surface area of ​​38-125 m2 / g.

Description

technical field

[0001] The present invention relates to a rubber composition for a rubber layer provided between a bead apex and a ply, and a tire having a rubber layer using the rubber composition. Background technique

[0002] In recent years, there has been an increasing demand for technology that can reduce the size and weight of tires used in passenger car tires for heavy electric vehicles, hybrid vehicles, and fuel cell vehicles. One of the causes of the decrease in tire durability can be exemplified by the separation of the bead apex and the carcass. The cause of the separation can be, for example, a phenomenon in which strain (distortion) generated along with deformation of the bead portion due to running is concentrated at a specific position (strain concentration), resulting in the phenomenon that the strain concentration and subsequent The resulting heat is prone to separation at specific locations. The position where separation is likely to occur can be exempli...

Examples

Embodiment 1～22 and comparative example 1～14

[0170] In the formulation content shown in Table 1 and Table 2, various chemicals except insoluble sulfur and vulcanization accelerator were kneaded with a Banbury mixer. The resulting kneaded product was discharged at 180°C, to which insoluble sulfur and a vulcanization accelerator were added, kneaded in an open roll, and discharged at 105°C, whereby an unvulcanized rubber composition was obtained. Test pieces were prepared by vulcanizing the unvulcanized rubber composition at 170° C. for 12 minutes, and the following tests were performed using the obtained test pieces. Furthermore, the above-mentioned unvulcanized rubber composition was molded with a single rubber extruder into image 3 The shape of the apex strip shown (average thickness: 1.0mm, h1: 60, h2: 15 for the apex strip 13, h1: 60, h2: 15 for the apex strip 14) should be attached to other tire components Unvulcanized tires were combined and press-vulcanized at 150° C. for 35 minutes to manufacture test tires (size...

Embodiment 23 and 24

[0172] In order to make the unvulcanized rubber composition Figure 5 (Example 23) and Figure 9The bead apex of the two-layer structure shown in (Example 24) was produced in the same manner as in the above-mentioned Example 1, except that the unvulcanized rubber composition of the bead apex formulation was molded with a double-two-layer extruder. The test tires were subjected to the tests shown below.

[0173]

[0174] The prepared test piece was cut into width 4mm, length 40mm, and thickness 2mm, and measured the complex modulus of elasticity (E * ) and loss tangent (tanδ) viscoelastic properties. The measurement conditions were: initial strain 10%, dynamic strain 2%, vibration frequency 10 Hz, temperature 70°C. E. * The value of α is 4 to 8 MPa, showing excellent driving stability and separation resistance (strain dispersibility). In addition, the smaller the value of tan δ, the better the low heat build-up property.

[0175]

[0176] According to JIS K6251, a ten...

technical field

[0001] The present invention relates to a rubber composition for a rubber layer provided between a bead apex and a ply, and a tire having a rubber layer using the rubber composition. Background technique

[0002] In recent years, there has been an increasing demand for technology that can reduce the size and weight of tires used in passenger car tires for heavy electric vehicles, hybrid vehicles, and fuel cell vehicles. One of the causes of the decrease in tire durability can be exemplified by the separation of the bead apex and the carcass. The cause of the separation can be, for example, a phenomenon in which strain (distortion) generated along with deformation of the bead portion due to running is concentrated at a specific position (strain concentration), resulting in the phenomenon that the strain concentration and subsequent The resulting heat is prone to separation at specific locations. The position where separation is likely to occur can be exempli...

Examples

Embodiment 1～22 and comparative example 1～14

[0170] In the formulation content shown in Table 1 and Table 2, various chemicals except insoluble sulfur and vulcanization accelerator were kneaded with a Banbury mixer. The resulting kneaded product was discharged at 180°C, to which insoluble sulfur and a vulcanization accelerator were added, kneaded in an open roll, and discharged at 105°C, whereby an unvulcanized rubber composition was obtained. Test pieces were prepared by vulcanizing the unvulcanized rubber composition at 170° C. for 12 minutes, and the following tests were performed using the obtained test pieces. Furthermore, the above-mentioned unvulcanized rubber composition was molded with a single rubber extruder into image 3 The shape of the apex strip shown (average thickness: 1.0mm, h1: 60, h2: 15 for the apex strip 13, h1: 60, h2: 15 for the apex strip 14) should be attached to other tire components Unvulcanized tires were combined and press-vulcanized at 150° C. for 35 minutes to manufacture test tires (size...

Embodiment 23 and 24

[0172] In order to make the unvulcanized rubber composition Figure 5 (Example 23) and Figure 9The bead apex of the two-layer structure shown in (Example 24) was produced in the same manner as in the above-mentioned Example 1, except that the unvulcanized rubber composition of the bead apex formulation was molded with a double-two-layer extruder. The test tires were subjected to the tests shown below.

[0173]

[0174] The prepared test piece was cut into width 4mm, length 40mm, and thickness 2mm, and measured the complex modulus of elasticity (E * ) and loss tangent (tanδ) viscoelastic properties. The measurement conditions were: initial strain 10%, dynamic strain 2%, vibration frequency 10 Hz, temperature 70°C. E. * The value of α is 4 to 8 MPa, showing excellent driving stability and separation resistance (strain dispersibility). In addition, the smaller the value of tan δ, the better the low heat build-up property.

[0175]

[0176] According to JIS K6251, a ten...

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