Pneumatic radial tire with low rolling resistance and high wet grip

Abstract

The invention provides a low-rolling-resistance and high-wet-grabbing pneumatic radial tire, which belongs to the technical field of tires, and comprises a tread and a circumferential groove extending along the circumferential direction of the tread, the contour between the highest point of the tread and the end point of one side of the tread is sequentially divided into a first arc section, a second arc section, a third arc section and a fourth arc section, the radius TR1 of the first section of arc, the radius TR2 of the second section of arc, the radius TR3 of the third section of arc and the radius TR4 of the fourth section of arc meet the following relation: TR1: TR2: TR3: TR4 = 2.3: 1.9: 1.6: 1; the number of the circumferential grooves is five, the five circumferential grooves sequentially comprise a central water-drop-shaped pattern groove, two pattern grooves close to the center and two shoulder water-drop-shaped pattern grooves from the center to the two sides of the tread, and the central water-drop-shaped pattern groove and the shoulder water-drop-shaped pattern grooves are grooves which are self-closed in a loading state; according to the invention, the tire structure design, the pattern design and the formula design are optimized, so that the tire has the ultimate durability, low rolling resistance and full-life-cycle high-wet-grip performance at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of tires, and in particular to a pneumatic radial tire with low rolling resistance and high wet grip. Background Art

[0002] When the tire is subjected to the ultimate endurance test, refer to Figure 1 , generally in a specific venue, the car drives in a circle along a fixed route. The route has continuous curves with a radius of R30 to R50. The lateral acceleration required for the tire when turning is 0.6g, and the turning line speed reaches 60 to 80km / h. When the car turns according to the above conditions, the maximum lateral force can reach more than 30,000N (compared to the lateral force of normal driving, it is more than 100 times higher), which can easily cause the rubber on the shoulder of the tire to tear off and then be damaged. This test is an endurance test under extreme conditions, which aims to evaluate the ability of the tire to resist lateral force when the vehicle is driving on multiple continuous curved roads, and tires with this durability have better crown durability performance than ordinary tires.

[0003] In recent years, with the continuous updating of laws and policies related to tires in various countries, the technical requirements for tires are not only the conventional safety durability and wear life, but also the requirements for low rolling resistance and high wet grip performance. In the EU regulation R117-04 that has just come into effect, not only the wetland performance of new tires is required, but also the tires are required to maintain a certain wetland performance throughout their life cycle.

[0004] Currently, there is no clear technical means for tires to have such extreme durability. Technologies to reduce tire rolling resistance include: optimizing tire tread pattern design, using low rolling resistance rubber formula, reducing component thickness, and reducing material usage; the main technologies to improve wet grip include: using high wet grip rubber formula, increasing the water storage volume of the tread groove, etc.

[0005] In order to achieve both low rolling resistance and high wet grip performance, the commonly used technical means in the structure of existing ordinary products is to reduce the thickness of components. The tread is the main heat-generating component of the tire. By reducing the tread thickness (reducing the amount of rubber), the rolling resistance can be effectively reduced. However, this technical means results in less rubber used in the crown of the tire. Under the action of lateral forces in extreme working conditions, the rubber on the shoulder of the tire wears out quickly, resulting in reduced durability. The commonly used technical means in the formulation is to adopt a silica formula with low hysteresis loss and high wet grip, but this formula has poor strength. Under the action of lateral forces in extreme working conditions, the shoulder of the tire is easily torn off, resulting in reduced durability.

[0006] At the same time, the existing high-wet grip pattern design adds more grooves on the tire surface to increase the water storage volume, while increasing the pattern edge density to improve the ability to puncture the water film. However, if low rolling resistance is also considered, in order to ensure the rigidity of the tread and suppress deformation, these grooves must be reduced as much as possible and as shallow as possible. Shallow grooves will be worn away in the middle and late stages of tire use, and wet performance will be greatly reduced. Therefore, it is difficult for conventional pattern designs to take into account both wet and rolling resistance performance. Summary of the invention

[0007] The present invention provides a pneumatic radial tire with low rolling resistance and high wet grip. By optimizing the structural design, pattern design and formula design of the tire, the tire has extreme durability while having low rolling resistance and high wet grip performance. In particular, the wet grip performance of the tire can be achieved throughout its entire life cycle.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] A pneumatic radial tire with low rolling resistance and high wet grip, comprising a tread and a circumferential groove extending along the circumferential direction of the tread, wherein the contour between the highest point of the tread and the end point on one side of the tread is sequentially divided into a first arc, a second arc, a third arc and a fourth arc, and the radius TR1 of the first arc, the radius TR2 of the second arc, the radius TR3 of the third arc and the radius TR4 of the fourth arc satisfy the following relationship: TR1:TR2:TR3:TR4=2.3:1.9:1.6:1;

[0010] There are five circumferential grooves, and the five circumferential grooves include a central teardrop-shaped groove, two grooves close to the central groove, and two shoulder teardrop-shaped grooves along the center of the tread to both sides. The central teardrop-shaped groove and the shoulder teardrop-shaped groove are self-closing grooves in a loaded state, and the two grooves close to the central groove are open grooves. The five circumferential grooves have groove depths of GD1, GD2, GD3, GD4, and GD5, respectively, and groove widths of GW1, GW2, GW3, GW4, and GW5, and satisfy the following relationship:

[0011] GD1=GD2=GD3=GD4=GD5, and GD1 / L=0.045±3%;

[0012] GW1=GW5, GW2=GW4, GW1:GW2:GW3=1.63±3%:3.88±3%:1±3%, and (GW1+GW2+GW3) / L=0.18±3%.

[0013] Preferably, the five circumferential grooves divide the tread into six pattern blocks, and the widths of the six pattern blocks along the width direction of the tread are A, B, C, D, E, and F, respectively, and satisfy the following relationship:

[0014] A=F,B=E,C=D;

[0015] Its pattern block width ratio A:B:C=(1.84±3%):(1.45±3%):(1.00±3%);

[0016] C / L = 0.09 ± 3%;

[0017] Wherein, L is the arc length of the tread along the tire width direction.

[0018] Preferably, the central teardrop-shaped groove and the shoulder teardrop-shaped groove include a zigzag groove section, a straight groove section and a teardrop groove section in sequence from outside to inside along the radial direction of the tire, wherein the maximum width of the zigzag groove section extending along the tread is w1, the width of the straight groove section along the axial direction of the tire is w2, the maximum width of the teardrop groove section along the axial direction of the tire is w3, and the following relationship is satisfied: w1: w2: w3 = 3.5 ± 3%: 1: 3 ± 3%.

[0019] Preferably, the angle between the zigzag groove segment along the tread extension direction and the tread circumferential centerline is 8°.

[0020] Preferably, the straight groove section has a depth h2 along the radial direction of the tire, and h2 ≥ 3 mm.

[0021] Preferably, the depth of the water drop groove section along the radial direction of the tire is h3, and h3≥4mm.

[0022] Preferably, the angle between the upper edge of the cavity at the bottom of the water drop groove section and the horizontal direction is α, and 45°≤α≤75°; the chamfer angle R at the bottom of the water drop groove section is ≥2mm.

[0023] Preferably, the tire further comprises a carcass arranged radially inwardly of the tread and a belt layer located between the tread and the carcass, wherein the belt layer comprises, in order from inside to outside along the radial direction of the tire, a first belt layer, a second belt layer, a third belt layer and a fourth belt layer.

[0024] Preferably, the width of the second belt layer along the axial direction of the tire is L1, and 90%≤L1 / L≤95%, the angle between the line between the center point Q of the crown of the second belt layer and the end point P on one side of the second belt layer and the horizontal direction is β, and 3°≤β≤7°.

[0025] Preferably, the distance between the end point on one side of the third belt layer and the end point on one side of the tread along the radial direction of the tire is H, and H≥11 mm.

[0026] Preferably, the tread comprises a crown layer in contact with the ground and a base layer arranged radially inward of the crown layer, and the maximum thickness of the base layer in the radial direction of the tire is h1, and h1=3 mm.

[0027] Preferably, the rubber material used in the crown layer has a hysteresis loss tangent value tanδ=0.098 and a modulus of 5.35 at 60°C and 5% deformation to ensure rolling resistance performance;

[0028] The rubber material used in the crown layer has a hysteresis loss angle tanδ=0.130 at 0°C to ensure wet grip performance;

[0029] The crown layer has a tensile strength Ts=29.5 MPa and a breaking elongation Eb=523% at room temperature, and below 120° C., the retention rate of Ts*Eb is 60% of that at room temperature.

[0030] Preferably, the rubber material used for the base layer has a hysteresis loss tangent value tanδ=0.030 at 60°C.

[0031] It can be seen from the above technical solutions that the present invention has the following beneficial effects:

[0032] 1. In the present invention, by optimizing the tire structure design, pattern design and formula design, the tire is achieved to have extreme durability, low rolling resistance and high wet grip performance throughout the life cycle. Specifically, the tread crown arc adopts a four-segment tangent arc design, the lengths of the four arcs are equal, and the arc radius meets a certain ratio requirement, so that the overall crown pressure distribution can be uniform, reducing rolling resistance, while also reducing shoulder pressure concentration, and improving extreme durability; the five crown grooves divide the tread into six pattern blocks, and the pattern blocks are designed in a certain ratio, so that the rigidity distribution of the crown part is reasonable, which is conducive to uniform wear of the crown, improves wear, and also ensures rolling resistance and extreme durability; the belt layer adopts a four-layer structure, and the width of the second belt layer meets a certain ratio with the tread arc length to improve Increase the rigidity of the shoulder position, reduce the deformation of the shoulder in the extreme endurance test, reduce the concentration of shoulder pressure, increase the area involved in wear, and thus improve the extreme endurance capacity; at the same time, the angle between the line between the middle position point of the second belt layer crown and the end point of one side of the second belt layer in the same horizontal direction meets a certain angle, so that in the extreme endurance test, the strain of the belt layer end point is small, which is beneficial to improving the extreme endurance performance; the groove depth and groove width ratio of the five grooves in the crown are set so that the grooves have a certain drainage performance while also ensuring the rolling resistance performance; for the teardrop-shaped grooves, the teardrop-shaped cavity at the bottom of the groove, when the tire is running in wet conditions, the water at the ground contact front can be discharged through this teardrop-shaped cavity, allowing the tire to enter the dry ground contact state earlier, greatly improving the wet performance of the tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the extreme endurance test;

[0034] Figure 2 A schematic diagram of the tire structure provided by the present invention;

[0035] Figure 3 for Figure 2 One of the partial schematic diagrams of the middle crown section;

[0036] Figure 4 A schematic diagram of the circumferential groove width of the tire provided by the present invention;

[0037] Figure 5 for Figure 2 Partial schematic diagram of the middle crown part (part 2);

[0038] Figure 6 It is a schematic diagram of the structure of a water drop-shaped groove;

[0039] Figure 7 A comparison chart of the ground contact pressure between the tire design provided by the present invention and the conventional design under extreme endurance conditions.

[0040] In the figure: 10, tread; 110, crown layer; 120, base layer; 130, central teardrop-shaped groove; 140, groove close to the central pattern; 150, shoulder teardrop-shaped groove; 210, zigzag groove section; 220, straight groove section; 230, teardrop groove section; 30, carcass; 40, belt layer; 410, first belt layer; 420, second belt layer; 430, third belt layer; 440, fourth belt layer. DETAILED DESCRIPTION

[0041] A preferred embodiment of the present invention is described in detail below with reference to the accompanying drawings.

[0042] To achieve the above purpose, the embodiment of the present invention adopts the following technical solution: Figure 2 , Figure 5 A pneumatic radial tire with low rolling resistance and high wet grip comprises a tread 10, wherein a circumferential groove is extended in the circumferential direction of the tread 10, and the contour from the highest point of the tread to the end point on one side of the tread is divided into a first arc, a second arc, a third arc and a fourth arc in sequence, and the radius TR1 of the first arc, the radius TR2 of the second arc, the radius TR3 of the third arc and the radius TR4 of the fourth arc satisfy the following relationship: TR1:TR2:TR3:TR4=2.3:1.9:1.6:1. According to this crown arc design, the overall crown pressure is evenly distributed, the rolling resistance is reduced, and the shoulder pressure concentration is also reduced, thereby improving the ultimate durability;

[0043] Further, see Figure 3 , Figure 4There are five circumferential grooves, which include a central teardrop-shaped groove 130, two grooves 140 near the central pattern and two shoulder teardrop-shaped grooves 150 along the center of the tread 10 to both sides, wherein the central teardrop-shaped groove and the shoulder teardrop-shaped groove are self-closing grooves in a loaded state, and the two grooves near the central pattern are open pattern grooves. The five circumferential grooves have a groove depth of GD1, GD2, GD3, GD4, and GD5, respectively, and a groove width of GW1, GW2, GD4, and GD5. W3, GW4, GW5, and satisfy the following relationship: GD1=GD2=GD3=GD4=GD5, and GD1 / L=0.045±3%; it should be noted that GW1=GW5, GW2=GW4, and GW1:GW2:GW3=1.63±3%:3.88±3%:1±3%, (GW1+GW2+GW3) / L=0.18±3%. In this way, the tread grooves designed according to the above proportions have a certain drainage performance and can also ensure rolling resistance.

[0044] Reference Figure 3 As a preferred technical solution of this embodiment, the five circumferential grooves divide the tread 10 into six pattern blocks, and the widths of the six pattern blocks along the width direction of the tread 10 are A, B, C, D, E, and F respectively, and satisfy the following relationship: A=F, B=E, C=D; the pattern block width ratio of the six pattern blocks is A:B:C=(1.84±3%):(1.45±3%):(1.00±3%); and C / L=0.09±3%; wherein L is the tread arc length of the tread 10 along the tire width direction, and the pattern block width designed according to this ratio makes the crown rigidity reasonably distributed, which is conducive to uniform wear of the crown and improves wear, while also ensuring rolling resistance performance and ultimate durability.

[0045] Further, see Figure 6 The central teardrop-shaped groove and the shoulder teardrop-shaped groove include a zigzag groove section 210, a straight groove section 220 and a teardrop groove section 230 from outside to inside in the radial direction of the tire, wherein the maximum width of the zigzag groove section along the tread is w1, the width of the straight groove section along the axial direction of the tire is w2, and the maximum width of the teardrop groove section along the axial direction of the tire is w3, and the following relationship is satisfied: w1: w2: w3 = 3.5 ± 3%: 1: 3 ± 3%;

[0046] Further, see Figure 4 , Figure 6The zigzag angle of the zigzag groove section 210 is 8°, so that the portion of the teardrop-shaped groove close to the tread adopts a zigzag groove, and the zigzag angle is preferably 8°. Specifically, the zigzag angle refers to the angle between the groove bottom of the zigzag groove section 210 (that is, the groove top of the straight groove section 220) along the extension direction of the tread 10 and the circumferential center line of the tread 10, which can improve the stone discharge capacity; at the same time, the middle groove of the teardrop-shaped groove adopts a straight groove to improve the drainage performance; and the lower half of the teardrop-shaped groove has a teardrop-shaped cavity. When the tire is running in wet conditions, the water at the ground contact front can be discharged through this teardrop-shaped cavity, allowing the tire to enter the dry ground contact state earlier, greatly improving the wet performance of the tire.

[0047] Further, see Figure 6 The straight groove section 220 has a depth of h2 along the radial direction of the tire, and h2 ≥ 3 mm. The groove designed in this way can be self-closed when the tire is loaded, so that the two tread blocks are similar to one tread block when contacting the ground, which significantly reduces the deformation of the tread during driving and effectively reduces rolling resistance. In the extreme endurance test, the self-closing of the water drop groove greatly enhances the rigidity of the shoulder tread blocks, reduces the deformation of the shoulder pattern, and further improves the extreme endurance capability.

[0048] At the same time, refer to Figure 6 The depth of the water drop groove section 230 along the radial direction of the tire is h3, and h3≥4mm, which can ensure that there is sufficient water storage volume and the tire has better wet performance.

[0049] Reference Figure 6 In some embodiments, the angle between the upper edge of the cavity at the bottom of the water drop groove section 230 and the horizontal direction is α, and 45°≤α≤75°. Preferably, α is 60°. At the same time, the chamfer R at the bottom of the water drop groove section 230 is ≥2mm. The water drop groove designed in this way can ensure sufficient wetland performance, reduce stress concentration at the bottom of the groove, and avoid tearing at the bottom of the groove.

[0050] In this way, the grooves designed in this way not only ensure rolling resistance, but also provide sufficient wet performance. The design of the special water drop grooves can ensure a certain wet performance throughout the tire's life cycle.

[0051] In some embodiments, reference Figure 3The tire also includes a carcass 30 arranged on the radial inner side of the tread 10 and a belt layer 40 located between the tread and the carcass. The belt layer includes a first belt layer 410, a second belt layer 420, a third belt layer 430 and a fourth belt layer 440 in order from the inside to the outside of the tire radial direction. Furthermore, the width of the second belt layer 420 along the axial direction of the tire is L1, and 90%≤L1 / L≤95%. Preferably, L1 / L=93%. Through this belt layer design, the rigidity of the shoulder position is improved, the deformation of the shoulder in the extreme endurance test is reduced, the concentration of shoulder pressure is reduced, and the area involved in wear is increased, thereby improving the extreme endurance capability.

[0052] Further, see Figure 5 , the angle between the line between the position point Q in the crown of the second belt layer and the end point P on one side of the second belt layer and the horizontal direction is β, and 3°≤β≤7°, preferably, β=5°, while the conventional design is usually ≤2°. In this state, the end of the second belt layer tends to collapse. In the extreme endurance test, due to the great lateral force that will cause the crown of the tire to deform, the collapsed end point of the second belt layer will rise and approach the horizontal. In this state, the strain of the belt end point is small during driving, which is beneficial to the extreme endurance performance.

[0053] Further, see Figure 3 The distance between the end point on one side of the third belt layer 430 and the end point on one side of the tread along the radial direction of the tire is H, and H≥11mm. This ensures that in the extreme endurance test, there is enough rubber material on the shoulder for wear, further improving the extreme endurance capability.

[0054] In some embodiments, reference Figure 5 The tread 10 includes a crown layer 110 in contact with the ground and a base layer 120 arranged radially inward of the crown layer. The rubber used in the crown layer 110 has a hysteresis loss angle tangent value tanδ=0.098 and a modulus of 5.35 at 60°C and 5% deformation to ensure rolling resistance; at the same time, at 0°C, the hysteresis loss angle tangent value tanδ=0.130 to ensure wet grip performance. The crown layer 110 has a tensile strength Ts=29.5MPa at room temperature, a tear elongation Eb of 523%, and a retention rate of Ts*Eb of 60% at room temperature at 120°C. When a long-term extreme endurance test is carried out, the tread rubber can still maintain a certain strength after the tread surface temperature rises, thereby improving the extreme endurance capability.

[0055] Further, see Figure 5The maximum thickness of the base layer 120 along the radial direction of the tire is h1, and h1=3mm. The rubber material used in the base layer 120 has a hysteresis loss tangent value tanδ=0.030 at 60°C. The base layer 120 mainly plays a heat dissipation role, so that the base layer 120 has a certain effect of reducing the rolling resistance of the tire, and can ensure that the crown layer has sufficient thickness for durability test wear, thereby ensuring the ultimate durability.

[0056] By conducting extreme endurance tests on tires with conventional designs and the designs of this application, it was found that the conventional designs had serious shoulder damage and the entire shoulder tread block was delaminated; while the designs of this application were more evenly stressed, each tread block was evenly worn, and no block fell off. Figure 7 Through the optimization of the above structure, in the FEA simulation, it can be seen that under the extreme endurance condition, the shoulder edge pressure of the optimized solution can be reduced by more than 60% compared with the conventional design. This can reduce the tire shoulder pressure value and make the overall pressure distribution more uniform. By using a more tear-resistant formula, tearing is less likely to occur, thereby significantly improving the extreme endurance capability.

[0057] The above-described embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A pneumatic radial tire with low rolling resistance and high wet grip, comprising a tread (10) and circumferential grooves extending along the circumferential direction of the tread, characterized in that: The contour between the highest point of the tread and the end point on one side of the tread is divided into a first arc, a second arc, a third arc and a fourth arc in sequence, and the radius TR1 of the first arc, the radius TR2 of the second arc, the radius TR3 of the third arc and the radius TR4 of the fourth arc satisfy the following relationship: TR1:TR2:TR3:TR4=2.3:1.9:1.6:1; Five circumferential grooves are provided, and the five circumferential grooves include a central teardrop-shaped groove (130), two grooves close to the central groove (140), and two shoulder teardrop-shaped grooves (150) in sequence from the center of the tread (10) to both sides. The central teardrop-shaped groove and the shoulder teardrop-shaped groove are self-closing grooves in a loaded state, and the two grooves close to the central groove are open grooves. The five circumferential grooves have groove depths of GD1, GD2, GD3, GD4, and GD5, respectively, and groove widths of GW1, GW2, GW3, GW4, and GW5, and satisfy the following relationship: GD1=GD2=GD3=GD4=GD5, and GD1 / L=0.045±3%; GW1=GW5, GW2=GW4, GW1:GW2:GW3=1.63±3%:3.88±3%:1±3%, and (GW1+GW2+GW3) / L=0.18±3%.

2. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 1, characterized in that: The five circumferential grooves divide the tread (10) into six pattern blocks, and the widths of the six pattern blocks along the width direction of the tread (10) are A, B, C, D, E, and F, respectively, and satisfy the following relationship: A=F,B=E,C=D; Its pattern block width ratio A:B:C=(1.84±3%):(1.45±3%):(1.00±3%); C / L = 0.09 ± 3%; Wherein, L is the tread arc length of the tread (10) along the tire width direction.

3. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 1, characterized in that: The central teardrop-shaped groove and the shoulder teardrop-shaped groove include a zigzag groove section (210), a straight groove section (220) and a teardrop groove section (230) in sequence from outside to inside along the radial direction of the tire, wherein the maximum width of the zigzag groove section extending along the tread is w1, the width of the straight groove section along the axial direction of the tire is w2, and the maximum width of the teardrop groove section along the axial direction of the tire is w3, and the following relationship is satisfied: w1: w2: w3 = 3.5 ± 3%: 1: 3 ± 3%.

4. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 3, characterized in that: The angle between the zigzag groove section (210) and the circumferential center line of the tread (10) along the extension direction of the tread (10) is 8°.

5. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 4, characterized in that: The straight groove section (220) has a depth h2 along the radial direction of the tire, and h2 is ≥ 3 mm.

6. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 5, characterized in that: The depth of the water drop groove section (230) along the radial direction of the tire is h3, and h3 is ≥ 4 mm.

7. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 6, characterized in that: The angle between the upper edge of the cavity at the bottom of the water drop groove section (230) and the horizontal direction is α, and 45°≤α≤75°; the chamfer angle R of the bottom of the water drop groove section (230) is ≥2mm.

8. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 1, characterized in that: The tire also includes a carcass (30) arranged radially inwardly of the tread (10) and a belt layer (40) located between the tread and the carcass, wherein the belt layer includes, from inside to outside along the radial direction of the tire, a first belt layer (410), a second belt layer (420), a third belt layer (430) and a fourth belt layer (440).

9. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 8, characterized in that: The width of the second belt layer (420) along the axial direction of the tire is L1, and 90%≤L1 / L≤95%, and the angle between the line between the crown midpoint Q of the second belt layer and the end point P on one side of the second belt layer and the horizontal direction is β, and 3°≤β≤7°.

10. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 9, characterized in that: The distance between the end point on one side of the third belt layer (430) and the end point on one side of the tread along the radial direction of the tire is H, and H is ≥ 11 mm.

11. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 1, characterized in that: The tread (10) comprises a crown layer (110) in contact with the ground and a base layer (120) arranged radially inside the crown layer, wherein the maximum thickness of the base layer (120) in the radial direction of the tire is h1, and h1=3 mm.

12. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 11, characterized in that: The rubber material used in the tire crown layer (110) has a hysteresis loss angle tangent value tanδ=0.098 and a modulus of 5.35 at 60°C and 5% deformation, so as to ensure rolling resistance performance; The rubber material used in the tire crown layer (110) has a hysteresis loss angle tanδ of 0.130 at 0°C to ensure wet grip performance; The crown layer (110) has a tensile strength Ts=29.5 MPa and a breaking elongation Eb=523% at room temperature, and below 120° C., the retention rate of Ts*Eb is 60% of that at room temperature.

13. The pneumatic radial tire with low rolling resistance and high wet grip according to claim 12, characterized in that: The rubber material used in the base layer (120) has a hysteresis loss tangent value tanδ=0.030 at 60°C.

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