CN104626886A - Pneumatic tire - Google Patents

Abstract

The invention provides a pneumatic tire (2) capable of preventing generation of groove cracks on tire surfaces and improving high-speed durability. The tire (2) is provided with a tire surface (4), a belted layer (16), and a reinforced layer (22). Horizontal grooves (46) extended substantially along an axial direction are disposed in the tire surface body(24) and the tire shoulder area (s) of the tire surface(4) in an etched manner. The reinforced layer (22) is constituted by rubber compositions. The rubber compositions comprise base rubber and short fibers (52). The lengths of the short fibers (52) is in a range from 1 (mu)m to 100 (mu)m. The proportion of the short fibers (52) can be in a range from 1 to 100 parts by mass with respect to the base rubber of 100 parts by mass. The reinforced layer (22) is disposed on the radial inner sides of the horizontal grooves. In the reinforced layer (22), the short fibers (52) can be oriented in the peripheral direction. The distance from the bottom parts of the horizontal grooves (46) to the thickness (t) of the reinforced layer (22) is lower than 2.0mm.

Description

Air-inflation tyre

Technical field

The present invention relates to air-inflation tyre.

Background technology

Usually, ditch is provided with quarter in the tread surface of tire.Tread contour is formed by this ditch.The rideability of tread contour to tire has an impact.As the example of the ditch of this tread contour of formation, the band ditch that there is tap drain circumferentially and extend vertically.

According to the viewpoint strengthening carcass, tire is made to possess bracing ply.Bracing ply the radially inner side of tyre surface and carcass stacked.Bracing ply comprises and many cords of row arrangement.Each cord tilts relative to the equatorial plane.Usually, the material of cord is steel.

When tire is to run at high speed, the axial Outboard Sections of bracing ply moves in the mode outstanding towards radial outside due to centnifugal force.The movement of this bracing ply is also referred to as protuberance (lifting).Deformation easily concentrates on the end of bracing ply.Further, be in the tire of motoring condition with heat, and the rubber of tire easily puts aside heat.Therefore, in the end of bracing ply, cord can be peeled off from the rubber be positioned at around it sometimes.The damage produced along with this stripping gets loose (BEL) also referred to as cushion layer edge.The high speed durability of this damage to tire has an impact.According to the viewpoint of high speed durability, various research is carried out to the structure of tire.The example of this research is disclosed in Japanese Unexamined Patent Publication 2006-160108 publication and Japanese Unexamined Patent Publication 2005-280458 publication.

Patent documentation 1: Japanese Unexamined Patent Publication 2006-160108 publication

Patent documentation 2: Japanese Unexamined Patent Publication 2005-280458 publication

In order to by suppressing accumulation of heat to improve high speed durability, sometimes adopt the tyre surface with less thickness.In this case, because the thickness of the tyre surface of ditch bottom also diminishes, therefore, easily crack is produced at bottom of trench.The damage produced along with crack at bottom of trench is also referred to as tyre surface ditch crackle (tread groove cracking, TGC).This damage is more remarkable in the tire with band ditch.

Summary of the invention

The object of the present invention is to provide a kind of air-inflation tyre, the generation of tyre surface ditch crackle can be prevented, the raising of high speed durability can be realized again.

Air-inflation tyre involved in the present invention possesses: tyre surface, and its outside face forms tread surface; Bracing ply, it is positioned at the radially inner side of above-mentioned tyre surface; And enhancement Layer, it is between above-mentioned tyre surface and above-mentioned bracing ply.Above-mentioned bracing ply comprises and many cords of row arrangement, and each cord tilts relative to the equatorial plane.Carve in the shoulder zone of above-mentioned tread surface and be provided with the band ditch extended roughly vertically.Above-mentioned enhancement Layer is formed by rubber composition.Above-mentioned rubber composition comprises base rubber and chopped fiber.The length of above-mentioned chopped fiber is more than 1 μm less than 100 μm.The proportional quantity of the above-mentioned chopped fiber comprised in above-mentioned rubber composition is below more than 1 mass parts 100 mass parts relative to the base rubber of 100 mass parts.Above-mentioned enhancement Layer is positioned at the radially inner side of above-mentioned band ditch.In above-mentioned enhancement Layer, above-mentioned chopped fiber orientation in the circumferential.Thickness t from the bottom of above-mentioned band ditch to above-mentioned enhancement Layer is below 2.0mm.

Preferably, in this air-inflation tyre, above-mentioned thickness t is below 1.5mm.

In air-inflation tyre involved in the present invention, the thickness t from the bottom of band ditch to enhancement Layer is below 2.0mm.T is less for this thickness.Thus, heat radiation is promoted.The part of the tyre surface of this tire is difficult to accumulation of heat.Enhancement Layer comprises chopped fiber, this chopped fiber orientation in the circumferential.This enhancement Layer is between tyre surface and bracing ply.This enhancement Layer contributes to the constraint to bracing ply.This enhancement Layer can suppress the protuberance of bracing ply.In this tire, by the synergistic effect of less thickness t and enhancement Layer, achieve the raising of high speed durability.

In this tire, enhancement Layer is positioned at the radially inner side of band ditch.As mentioned above, enhancement Layer comprises chopped fiber, this chopped fiber orientation in the circumferential.The generation of this enhancement Layer to the crack at the bottom place of band ditch is suppressed.Even if generation crack, this enhancement Layer also can suppress the development in this crack.In this tire, although adopt less thickness t, also can prevent the generation of tyre surface ditch crackle.

According to the present invention, following air-inflation tyre can be obtained, the generation of tyre surface ditch crackle can be prevented, the raising of high speed durability can be realized again.

Accompanying drawing explanation

Fig. 1 is the cutaway view of the airtyred part illustrated involved by an embodiment of the invention.

Fig. 2 is the expansion drawing of a part for the tread surface of the tire that Fig. 1 is shown.

Fig. 3 is the cutaway view along III in Fig. 1-III line.

Fig. 4 is the amplification view of the enhancement Layer illustrated in Fig. 3.

Fig. 5 is the schematic diagram that the chopped fiber comprised in the enhancement Layer of Fig. 4 is shown.

Fig. 6 is the block diagram of the band illustrated for enhancement Layer.

Fig. 7 is the cutaway view of the airtyred part illustrated involved by another embodiment of the invention.

Fig. 8 is the cutaway view along VIII in Fig. 7-VIII line.

The explanation of Reference numeral:

2,62... tire; 4,64... tyre surface; 16,76... bracing ply; 22,84... enhancement Layer; 24,86... tread surface; 26,88... ditch; 28,96... basic unit; 30,98... top layer; 38,100... la m; 40, layer outside 102...; 46,94... band ditch; 52... chopped fiber; 54... matrix; 78... string course.

Detailed description of the invention

Below, suitably with reference to accompanying drawing, and the present invention is described in detail according to preferred implementation.

Figure 1 illustrates air-inflation tyre 2.In FIG, above-below direction is the radial direction of tire 2, and left and right directions is the axis of tire 2, is the circumference of tire 2 relative to the vertical direction of paper.In FIG, long and short dash line CL represents the equatorial plane of tire 2.For the shape of this tire 2, except tread contour, all the other are all symmetrical relative to the equatorial plane.

This tire 2 possesses tyre surface 4, sidewall 6, alar part 8, limit oral area 10, tyre bead 12, carcass 14, bracing ply 16, liner 18, chafer 20 and enhancement Layer 22.This tire 2 is tubeless tiress.This tire 2 is installed on car.

Tyre surface 4 is in the shape protruded towards radial outside.Tyre surface 4 is formed with the tread surface 24 contacted with road surface.Ditch 26 is provided with quarter at tyre surface 4.Tread contour is formed by this ditch 26.

Tyre surface 4 has basic unit 28 and table (cap) layer 30.Top layer 30 is positioned at the radial outside of basic unit 28.Top layer 30 is laminated in basic unit 28.Basic unit 28 is made up of the cross-linked rubber of adhesive bonding property excellence.The typical base rubber of basic unit 28 is natural rubbers.Top layer 30 is made up of the cross-linked rubber of abrasion test, resistance to effect of heat and adherence properties excellence.

Sidewall 6 roughly extends towards radially inner side from the end of tyre surface 4.The radial outside end on this sidewall 6 engages with tyre surface 4.The radially inner side end on this sidewall 6 engages with limit oral area 10.This sidewall 6 is made up of cutting resistance and the cross-linked rubber that has excellent weather resistance.This sidewall 6 is for preventing the damage of carcass 14.

Alar part 8 is between tyre surface 4 and sidewall 6.Alar part 8 engages with tyre surface 4 and sidewall 6 respectively.Alar part 8 is made up of the cross-linked rubber of adhesive bonding property excellence.

Limit oral area 10 is roughly positioned at the radially inner side on sidewall 6.In the axial direction, limit oral area 10 is positioned at than tyre bead 12 and carcass 14 position in the outer part.Limit oral area 10 is made up of the cross-linked rubber of excellent in wear resistance.Limit oral area 10 abuts with the flange of wheel rim.

Tyre bead 12 is positioned at the axially inner side of limit oral area 10.Tyre bead 12 possesses: bead core 32; And the triangle rubber 34 to extend from this bead core 32 towards radial outside.Bead core 32 is ring-type, and containing the non-telescoping wire rod after winding.The typical material of wire rod is steel.The end of triangle rubber 34 attenuates towards radial outside.Triangle rubber 34 is made up of the cross-linked rubber of high hardness.

Carcass 14 is made up of casingply 36.Casingply 36 is set up between the tyre bead 12 of both sides, and along tyre surface 4 and sidewall 6.Casingply 36 is turned back inside axially around bead core 32 outside axially.Principal part 36a and return portion 36b is formed with at casingply 36 because this is turned back.

Casingply 36 by and many cords of row arrangement and rubberizing form, but this to be illustrated.Each cord is 75 ° to 90 ° relative to the absolute value of equatorial plane angulation.In other words, this carcass 14 has radial structure.Cord is made up of organic fiber.As preferred organic fiber, can illustrate and poly-ester fibres, nylon fiber, rayon fiber, PEN fiber and aramid fibre are shown.Carcass 14 can be formed by the casingply 36 of more than 2 layers.

Bracing ply 16 is positioned at the radially inner side of tyre surface 4.Bracing ply 16 is stacked with carcass 14.Bracing ply 16 pairs of carcasses 14 are strengthened.Bracing ply 16 is made up of la m 38 and outside layer 40.From Fig. 1 clearly, in the axial direction, the width of la m 38 is more bigger than the width of outside layer 40.La m 38 and outside layer 40 respectively by and many cords of row arrangement and rubberizing form, but this to be illustrated.Each cord tilts relative to the equatorial plane.Usually, the absolute value at angle of inclination is more than 10 ° less than 35 °.The cord of la m 38 is contrary relative to the direction of tilt of the equatorial plane with the cord of outside layer 40 relative to the direction of tilt of the equatorial plane.The preferred material of cord is steel.Cord can use organic fiber.The axial width of preferred bracing ply 16 is more than 0.7 times of the amplitude peak of tire 2.Bracing ply 16 can possess the layer of more than 3 layers.

Liner 18 is positioned at the inner side of carcass 14.Liner 18 engages with the inside face of carcass 14.Liner 18 is made up of cross-linked rubber.Liner 18 uses the rubber of blocking property of air excellence.The typical base rubber of liner 18 is butyl rubber or halogenated butyl rubber.Liner 18 is pressed in tire 2 for keeping.

Chafer 20 is positioned near tyre bead 12.If tire 2 is assembled in wheel rim, then this chafer 20 abuts with wheel rim.Protected near tyre bead 12 by this abutting.In the present embodiment, chafer 20 is made up of cloth and the rubber that impregnated in this cloth.This chafer 20 can form as one with limit oral area 10.In this case, the material of chafer 20 is set to identical with the material of limit oral area 10.

Enhancement Layer 22 is between the basic unit 28 and bracing ply 16 of tyre surface 4.A pair enhancement Layer 22 is provided with in this tire 2.Each enhancement Layer 22 configured separate in the axial direction.In this tire 2, enhancement Layer 22 is arranged at shoulder zone S.As shown in the figure, the end of bracing ply 16 covers by enhancement Layer 22.Specifically, the end of the end of the la m 38 of bracing ply 16 and outside layer 40 thereof covers by this enhancement Layer 22.In addition, one deck enhancement Layer 22 with the width larger than the width of bracing ply 16 can be set, and utilize this one deck enhancement Layer 22 to be covered each for bracing ply 16 end.

In this tire 2, enhancement Layer 22 is formed by rubber composition.In other words, enhancement Layer 22 is made up of the material making rubber composition be cross-linked.This rubber composition comprises base rubber.As this base rubber, can illustrate and natural rubber, poly-butadiene, SB, polyisoprene, ethylene-propylene-diene terpolymer, poly-meric 2-chlorobutadiene, acrylonitrile-butadiene copolymer and isobutylene-isoprene copolymer are shown.Also can use rubber of more than two kinds simultaneously.

The rubber composition of enhancement Layer 22 also comprises chopped fiber.Chopped fiber can contribute to the intensity of enhancement Layer 22.As this chopped fiber, can illustrate shown with organic fiber.As organic fiber, can illustrate and nylon fiber, rayon fiber, aramid fibre, PEN fiber and poly-ester fibres are shown.According to the lightweight of quality and the viewpoint of cost degradation, as this chopped fiber, can use by making the raw material paper be made up of craft paper and old newspaper become fragment and the paper fiber of pulling an oar to it and obtaining.

The rubber composition of preferred enhancement Layer 22 comprises sulphur.Utilize sulphur that rubber molecule is cross-linked to each other.Other crosslinking agent can be used or replace sulphur and use other crosslinking agent together with sulphur.Electron ray can be utilized to be cross-linked.

The rubber composition of preferred enhancement Layer 22 comprises sulphur and vulcanization accelerator.Sulfenamide system vulcanization accelerator, guanidine system vulcanization accelerator, thiazole system vulcanization accelerator, thiuram system vulcanization accelerator, dithiocar-bamate system vulcanization accelerator etc. can be used.

The rubber composition of enhancement Layer 22 comprises reinforcement material.Typical reinforcement material is carbon black.FEF, GPF, HAF, ISAF, SAF etc. can be used.From the viewpoint of the intensity of enhancement Layer 22, the amount of preferred carbon black is more than 5 mass parts relative to the base rubber of 100 mass parts.From the viewpoint of the flexibility of enhancement Layer 22, the amount of preferred carbon black is below 50 mass parts.Silicon dioxide can be used or replace carbon black and use silicon dioxide together with carbon black.Dry silicon dioxide and the silicon dioxide of humidity can be used.

The rubber composition of enhancement Layer 22 comprises soften flux.As preferred soften flux, can illustrate and alkane hydrocarbon system processing oil, cycloalkanes hydrocarbon system processing oil and fragrant family processing oil are shown.From the viewpoint of the flexibility of enhancement Layer 22, the amount of preferred soften flux is more than 10 mass parts relative to the base rubber of 100 mass parts.From the viewpoint of the intensity of enhancement Layer 22, the amount of preferred soften flux is below 40 mass parts.

As required, the rubber composition to enhancement Layer 22 adds stearic acid, zinc oxide, ageing resistant, wax (wax), crosslinking coagent etc.

Figure 2 illustrates the expansion drawing of the tread surface 24 of this tire 2.A part for the tread contour of this tire 2 has been shown in this Fig. 2.In this Fig. 2, left and right directions is axially, and above-below direction is circumference.The direction vertical with paper is the radial direction of tire 2.

As shown in the figure, tread contour is made up of many ditches 26.In this tire 2, tread contour possesses the first tap drain 42, second tap drain 44, band ditch 46, oblique groove 48 and longitudinal furrow 50.

First tap drain 42 is positioned on the equatorial plane.First tap drain 42 circumferentially.In this tire 2, the degree of depth of the first tap drain 42 is more than 4mm below 9mm.The width of the first tap drain 42 is more than 1.5mm below 10mm.

Second tap drain 44 is positioned at the axially outside of the first tap drain 42.Second tap drain 44 circumferentially.In this tire 2, the degree of depth of the second tap drain 44 is more than 4mm below 9mm.The width of the second tap drain 44 is more than 2mm below 16mm.

Band ditch 46 is positioned at the axially outside of the second tap drain 44.Band ditch 46 extends roughly vertically.In the present invention, the band ditch 46 being less than 10 ° relative to the absolute value of the angle of the axis of tire 2 is called as " the band ditch extended roughly vertically ".In this tire 2, the degree of depth of band ditch 46 is more than 4mm below 8mm.The width of band ditch 46 is more than 2mm below 4mm.The length of band ditch 46 is more than 20mm below 60mm.Many band ditches 46 are provided with in the tread contour of this tire 2.These band ditches 46 configure in the circumferential at spaced intervals.

Oblique groove 48 is presented axially between the first tap drain 42 and the second tap drain 44.Oblique groove 48 tilts relative to the equatorial plane and extends to the equatorial plane from the second tap drain 44.Oblique groove 48 is communicated with the second tap drain 44, and is not communicated with the first tap drain 42.The bearing of trend of oblique groove 48 is more than 50 ° less than 60 ° relative to the absolute value of circumferential angulation.In this tire 2, the degree of depth of oblique groove 48 is more than 2mm below 8mm.The width of oblique groove 48 is more than 1.5mm below 5mm.The length of oblique groove 48 is more than 10mm below 40mm.

Longitudinal furrow 50 is positioned at the axially outside of band ditch 46.Longitudinal furrow 50 circumferentially.Longitudinal furrow 50 is communicated with band ditch 46.In this tire 2, the degree of depth of longitudinal furrow 50 is more than 0.2mm below 2.0mm.The width of longitudinal furrow 50 is more than 1.0mm below 3.0mm.The length of longitudinal furrow 50 is more than 10mm below 60mm.Many longitudinal furrows 50 are provided with in the tread contour of this tire 2.These longitudinal furrows 50 configure in the circumferential at spaced intervals.

In this tire 2, the first tap drain 42, second tap drain 44 and oblique groove 48 are arranged at the middle section C of tread surface 24.Band ditch 46 and longitudinal furrow 50 are arranged at the shoulder zone S of this tread surface 24.In fig. 2, double-head arrow WA represents the developed width of tread surface 24.This developed width WA is equal to the girth of the end of the tread surface 24 of the opposing party with the end of the tread surface 24 from a side.Solid line L1 and L2 represents the border of middle section C and shoulder zone S respectively.Be middle section C from border L1 to the region of border L2, the region from the end of the region of end to border L1 of tread surface 24 of a side and the tread surface from the opposing party 24 to border L2 is shoulder zone S.In fig. 2, double-head arrow WC is the width of middle section C.In this tire 2, width W C is less than more than 0.3 0.6 relative to the ratio of width W A.

Fig. 3 is the cutaway view along III in Fig. 1-III line.In this Fig. 3, show the part of the band ditch 46 of tyre surface 4.This III-III line is by from the bottom of band ditch 46 to the straight line of the minimum position of the thickness of bracing ply 16.In this Fig. 3, above-below direction is the radial direction of tire 2, and left and right directions is the circumference of tire 2.As shown in the figure, enhancement Layer 22 is positioned at the radially inner side of band ditch 46.

In this Fig. 3, double-head arrow t represents the thickness from the bottom of band ditch 46 to enhancement Layer 22.This thickness t is the thickness of the tyre surface 4 at the bottom place of band ditch 46.Double-head arrow tf represents the thickness of enhancement Layer 22.Double-head arrow tb represents the thickness from the bottom of band ditch 46 to bracing ply 16.This thickness tb equals thickness t and thickness tf sum (t+tf).

In this tire 2, thickness t is below 2.0mm.T is less for this thickness.Thus, heat radiation is promoted.The part of the tyre surface 4 of this tire 2 is difficult to accumulation of heat.The high speed excellent in te pins of durability of this tire 2.Less thickness t can contribute to lightweight.In this tire 2, lightweight can also be realized.And less quality can contribute to the reduction of rolling resistance.According to this viewpoint, preferably this thickness t is below 1.5mm.Because this thickness t is more little more preferred, so, this thickness t can be set as 0.0mm.In this case, enhancement Layer 22 exposes in the bottom of band ditch 46.

Fig. 4 is the amplification view of the part that Fig. 3 is shown.In this Fig. 4, enhancement Layer 22 is shown.In this Fig. 4, above-below direction is the radial direction of tire 2, and left and right directions is the circumference of tire 2.

As shown in the figure, the enhancement Layer 22 of this tire 2 is configured to possess many chopped fibers 52, matrix (matrix) 54.In other words, this enhancement Layer 22 is strengthened rubber (FRR) by fiber and is formed.These chopped fibers 52 disperse in matrix 54.The long side direction of these chopped fibers 52 roughly circumferentially.In this enhancement Layer 22, chopped fiber 52 orientation in the circumferential.Chopped fiber 52 can contribute to the intensity of enhancement Layer 22 effectively.

Fig. 5 is the schematic diagram of the chopped fiber 52 of the enhancement Layer 22 illustrated in Fig. 4.In Figure 5, left and right directions is circumference.Arrow theta represents the angle of chopped fiber 52.Angle θ is the absolute value of straight line X1 and straight line X2 angulation.Straight line X1 circumferentially.Straight line X2 passes through from one end 56 of chopped fiber 52 and the other end 58.This angle θ is that the long side direction of chopped fiber 52 is relative to circumferential angulation.Angle θ is more than 0 ° less than 90 °.

The rigidity of tire 2 effectively can be contributed to from the viewpoint of enhancement Layer 22, be that the quantity of the chopped fiber 52 of less than 20 ° is for the ratio of the sum of chopped fiber 52 for angle θ, be preferably more than 50%, be more preferably more than 70%, especially preferably more than 90%.In the calculating of ratio, the angle of the chopped fiber 52 exposed in cross section circumferentially of enhancement Layer 22 is measured.For 100 chopped fibers 52 of random selection, carry out the measurement of angle θ.In addition, angle θ is the quantity of the chopped fiber 52 of less than 20 ° is the situation of more than 90% relative to the ratio of the sum of chopped fiber 52, is the state of chopped fiber 52 orientation in the circumferential of enhancement Layer 22.

The enhancement Layer 22 of this tire 2 comprises chopped fiber 52, this chopped fiber 52 orientation in the circumferential.Enhancement Layer 22 is laminated in bracing ply 16.Enhancement Layer 22 pairs of bracing plys 16 move forward into row constraint.Because the end of bracing ply 16 covers by enhancement Layer 22, therefore, the protuberance of bracing ply 16 is suppressed effectively.And because the thickness t of the tyre surface 4 at the bottom place of band ditch 46 is set as below 2.0mm, therefore, the part of the tyre surface 4 of this tire 2 is difficult to accumulation of heat.In this tire 2, due to the synergistic effect of less thickness t and enhancement Layer 22, achieve the raising of high speed durability.

As mentioned above, enhancement Layer 22 is positioned at the radially inner side of band ditch 46.In this tire 2, because enhancement Layer 22 comprises chopped fiber 52, and this chopped fiber 52 orientation in the circumferential, therefore, the generation in the crack at the bottom place of band ditch 46 is suppressed.Even if suppose to create crack, this enhancement Layer 22 also can suppress the development in this crack.In this tire 2, although adopt less thickness t, also can prevent the generation of tyre surface ditch crackle (TGC).

According to the present invention, the air-inflation tyre 2 that can prevent the generation of tyre surface ditch crackle from can realize again the raising of high speed durability can be obtained.

In this tire 2, the thickness tf of preferred enhancement Layer 22 is more than 0.3mm below 3.0mm.By this thickness tf is set as more than 0.3mm, make enhancement Layer 22 effectively can contribute to the rigidity of tire 2.In this tire 2, both prevent the generation of TGC, achieve again the raising of high speed durability.According to this viewpoint, more preferably this thickness tf is more than 0.5mm.By this thickness tf is set as below 3.0mm, the impact of enhancement Layer 22 on the rigidity of tire 2 is suppressed.Owing to suitably maintaining the quality of tire 2, therefore, it is possible to prevent the increase of rolling resistance.According to this viewpoint, more preferably this thickness tf is below 2.0mm.

In this tire 2, the proportional quantity of the chopped fiber 52 comprised in the rubber composition of enhancement Layer 22 is below more than 1 mass parts 100 mass parts relative to the base rubber of 100 mass parts.By the proportional quantity of this chopped fiber 52 is set as more than 1 mass parts, enhancement Layer 22 is made to have the intensity of appropriateness.This enhancement Layer 22 can contribute to preventing the generation of TGC and the raising of high speed durability.According to this viewpoint, preferably the proportional quantity of this chopped fiber 52 is more than 2 mass parts.By the proportional quantity of chopped fiber 52 is set as below 100 mass parts, chopped fiber 52 can fully be engaged with the rubber existed around this chopped fiber 52.The excellent in te pins of durability of this tire 2.According to this viewpoint, preferably the proportional quantity of this chopped fiber 52 is below 90 mass parts.

In this tire 2, the average length L of chopped fiber 52 is more than 1 μm less than 100 μm.By average length L is set as more than 1 μm, in enhancement Layer 22, achieve chopped fiber 52 orientation in the circumferential.This enhancement Layer 22 can contribute to preventing the generation of TGC and the raising of high speed durability.According to this viewpoint, preferably this average length L is more than 5 μm.By average length L is set as less than 100 μm, chopped fiber 52 can be disperseed in matrix 54 well, and, chopped fiber 52 can fully be engaged with the rubber existed around this chopped fiber 52.The excellent in te pins of durability of this tire 2.According to this viewpoint, preferred average length L is less than 90 μm.In addition, this average length L is represented by the aviation value 100 chopped fibers 52 of random selection being carried out to the length measuring gained.Utilize stereomicroscope to observe chopped fiber 52, and the length that it passes through is measured, obtain the length of each chopped fiber 52 thus.

In this tire 2, the mean diameter D of preferred chopped fiber 52 is more than 0.04 μm.By the chopped fiber 52 that mean diameter D is more than 0.04 μm, the intensity of enhancement Layer 22 is able to abundant raising.According to the viewpoint of the dispersiveness to matrix 54, preferred average diameter D is less than 500 μm.In addition, this mean diameter D is represented by the aviation value 100 chopped fibers 52 of random selection being carried out to the diameter measuring gained.The diameter of stereomicroscope to this chopped fiber 52 is utilized to measure.

Tire 2 for the above-described, manufactures in the following manner.In this manufacture method, get out core.This core possesses the outside face of belt wire, but illustrates this.This outside face be filled with air and interior pressure remain 5% of regular interior pressure state under tire 2 inner surface configuration be similar to.

In this manufacture method, be wound with liner 18 at the outside face of core.Liner 18 is wound with casingply 36.After assembling tyre bead 12, form sidewall 6 and limit oral area 10.After bracing ply 16 is laminated in casingply 36, form enhancement Layer 22.

In this manufacture method, before enhancement Layer 22 is formed, the rubber composition being used for enhancement Layer 22 is extruded, form the band 60 shown in Fig. 6 thus.In figure 6, the direction shown in arrow B is the length direction of this band 60.This length direction be also band 60 extrude direction.

In this manufacture method, band 60 is shaping in the mode that its cross sectional shape is rectangular.As mentioned above, the rubber composition of enhancement Layer 22 comprises chopped fiber 52.Therefore, this band 60 also comprises chopped fiber 52.Because band 60 is shaping by extruding rubber composition, therefore, in this band 60, chopped fiber 52 extrudes orientation on direction at it, in other words, and orientation in their length direction.Here, " in the longitudinal direction orientation " refers to, the long side direction of chopped fiber 52 is the quantity of the chopped fiber 52 of less than 20 ° relative to the length direction angulation of band 60 is the situation of more than 90% relative to the ratio of the sum of chopped fiber 52.For the long side direction of the chopped fiber 52 of this band 60 relative to the length direction angulation of band 60, the method identical with the method for measurement of the angle θ of above-mentioned enhancement Layer 22 is utilized to measure.In addition, in the calculating of ratio, the angle of the chopped fiber 52 that the surface at band 60 is exposed is measured.

In this manufacture method, band 60 is circumferentially wound into spiral fashion in the mode covered the end of bracing ply 16.Thus, strengthened layer 22.As mentioned above, in this band 60, chopped fiber 52 orientation in their length direction.Therefore, in the enhancement Layer 22 obtained by this manufacture method, chopped fiber 52 orientation in the circumferential.

In this manufacture method, after formation enhancement Layer 22, form basic unit 28 and top layer 30.Identical with above-mentioned enhancement Layer 22, utilize the band that formed by respective rubber composition and form basic unit 28 and top layer 30.Obtain tyre surface 4 thus, the assembling of green tire (uncrosslinked tire 2) is complete.In this manufacture method, molding procedure is called as to the operation that green tire is assembled.

In this manufacture method, green tire is for vulcanization process.In vulcanization process, green tire is put in mould (not shown).The outside face of green tire abuts with the cavity surface of mould.Green tire is pressurized and heating in mould.By pressurizeing and heating, make the rubber composition flows of green tire.Make by heating rubber produce cross-linking reaction, thus obtain the tire 2 shown in Fig. 1.

As mentioned above, in this manufacture method, form enhancement Layer 22 by the circumferential band 60 being wound into spiral fashion.Therefore, in this enhancement Layer 22, do not exist as utilized the situation of a sheet material formation enhancement Layer, by reeling to sheet material and the seam making one end of this sheet material engage with its other end and formed.The form of this enhancement Layer 22 is not special.This enhancement Layer 22 can contribute to the raising of homogeneity.Due to while carry out winding while repair the form of enhancement Layer 22 to band 60, therefore, it is possible to suitably maintain the use amount of rubber, but also without the need to arranging the operation being used for repairing the form of enhancement Layer 22 in addition.This manufacture method can prevent the increase of the quality of tire 2, and can contribute to the raising of capacity rating.

In figure 6, double-head arrow Ts represents the thickness of the band 60 for enhancement Layer 22.Double-head arrow Ws represents the width of this band 60.

In this manufacture method, according to the viewpoint of the raising of capacity rating and homogeneity, preferred thickness ts is more than 0.3mm below 2.0mm.Preferable width Ws is more than 5mm below 50mm.

In the present invention, tire 2 is being assembled in regular wheel rim and under state tire 2 being inflated to regular interior pressure, the size of each parts of tire 2 and angle are being measured.When measuring, not to tire 2 applied load.In this manual, regular wheel rim refers to the wheel rim specified under the specification of tire 2 foundations." Design Rim " under " standard rim " under JATMA specification, TRA specification and " the Measuring Rim " under ETRTO specification is regular wheel rim.In this manual, regular interior pressure refer to and to specify under the specification of tire 2 foundations in pressure." most anticyclonic pressure " under JATMA specification, " " INFLATION PRESSURE " under " maxim " described in " TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES " under TRA specification and ETRTO specification is all regular interior pressure.When passenger car tire 2, under the state that interior pressure is 180kPa, size and angle are measured.For size and the angle of each parts of tire 2 described later, also measure in the same way.

Figure 7 illustrates the air-inflation tyre 62 involved by another embodiment of the invention.In the figure 7, above-below direction is the radial direction of tire 62, and left and right directions is the axis of tire 62, and the direction vertical with paper is the circumference of tire 62.In the figure 7, long and short dash line CL represents the equatorial plane of tire 62.For the shape of this tire 62, except tread contour, all the other are all symmetrical relative to the equatorial plane.

This tire 62 possesses tyre surface 64, sidewall 66, alar part 68, limit oral area 70, tyre bead 72, carcass 74, bracing ply 76, string course 78, liner 80, chafer 82 and enhancement Layer 84.This tire 62 is tubeless tires.This tire 62 is installed on car.In this tire 62, except tyre surface 64, string course 78 and enhancement Layer 84, all the other have the structure identical with the structure of the tire 2 shown in Fig. 1.

Tyre surface 64 is in the shape protruded towards radial outside.Tyre surface 64 is formed with the tread surface 86 contacted with road surface.Ditch 88 is provided with quarter at tyre surface 64.Tread contour is formed by this ditch 88.Tread contour shown in this tread contour with Fig. 2 is equal to.In this Fig. 7, show the first tap drain 90, second tap drain 92 and band ditch 94 in the ditch 88 forming tread contour.First tap drain 90 and the second tap drain 92 are arranged at the middle section C of tread surface 86.First tap drain 90 and the second tap drain 92 are respectively circumferentially.Band ditch 94 is arranged at the shoulder zone S of this tread surface 86.Band ditch 94 extends roughly vertically.

Tyre surface 64 has basic unit 96 and top layer 98.Basic unit 96 is between top layer 98 and string course 78.Basic unit 96 is made up of the cross-linked rubber of adhesive bonding property excellence.The typical base rubber of basic unit 96 is natural rubbers.Top layer 98 is made up of the cross-linked rubber of abrasion test, resistance to effect of heat and adherence properties excellence.

Bracing ply 76 is positioned at the radially inner side of tyre surface 64.The structure of this bracing ply 76 is equal to the structure of the bracing ply 16 of the tire 2 shown in Fig. 1.This bracing ply 76 is made up of la m 100 and outside layer 102.La m 100 and outside layer 102 comprise and many cords of row arrangement respectively.Each cord tilts relative to the equatorial plane.

String course 78 is positioned at the radial outside of bracing ply 76.In the axial direction, the width of string course 78 is larger than the width of bracing ply 76.This string course 78 is also referred to as full string course.This string course 78 is made up of cord and rubberizing, but does not illustrate this.Cord is wound into spiral fashion.This string course 78 has so-called seamless (jointless) structure.Cord in fact circumferentially.Cord is less than 5 ° relative to the angle of circumference, in addition, is less than 2 °.Owing to utilizing this cord to retrain bracing ply 76, therefore, the protuberance of bracing ply 76 is suppressed.Cord is made up of organic fiber.As preferred organic fiber, can illustrate and nylon fiber, poly-ester fibres, rayon fiber, PEN fiber and aramid fibre are shown.

Enhancement Layer 84 is between tyre surface 64 and bracing ply 76.Specifically, this enhancement Layer 84 is between the top layer 98 and string course 78 of tyre surface 64.In this tire 62, be provided with a pair enhancement Layer 84.Each enhancement Layer 84 configured separate in the axial direction.In the tire 62 shown in this Fig. 7, enhancement Layer 84 is arranged at shoulder zone S.

In this tire 62, enhancement Layer 84 is positioned at the axially outside of basic unit 96.As shown in the figure, top layer 98 is laminated in the parts be made up of basic unit 96 and a pair enhancement Layer 84.In this tire 62, between enhancement Layer 84 and top layer 98, there is not basic unit 96.In addition, the entirety of the basic unit 96 of tyre surface 64 can be made up of this enhancement Layer 84.In this case, top layer 98 entirety of tyre surface 64 is laminated in enhancement Layer 84.

In this tire 62, between enhancement Layer 84 and bracing ply 76, accompany string course 78.The end of bracing ply 76 covers across string course 78 by enhancement Layer 84.As shown in the figure, the la m 100 of bracing ply 76 end and outside it end of layer 102 covered by string course 78 and bracing ply 76 respectively.

Fig. 8 is the cutaway view along VIII in Fig. 7-VIII line.The part of the band ditch 94 of tyre surface 64 has been shown in this Fig. 8.This VIII-VIII line is by from the bottom of band ditch 94 to the straight line of the minimum position of the thickness of string course 78.In this Fig. 8, above-below direction is the radial direction of tire 62, and left and right directions is the circumference of tire 62.As shown in the figure, enhancement Layer 84 is positioned at the radially inner side of band ditch 94.

In this Fig. 8, double-head arrow t represents the thickness from the bottom of band ditch 94 to enhancement Layer 84.This thickness t is the thickness of the tyre surface 64 at the bottom place of band ditch 94.Double-head arrow tf represents the thickness of enhancement Layer 84.Double-head arrow tb represents the thickness from the bottom of band ditch 94 to string course 78.This thickness tb equals thickness t and thickness tf sum (t+tf).

In this tire 62, thickness t is below 2.0mm.T is less for this thickness.Thus, heat radiation is promoted.The part of the tyre surface 64 of this tire 62 is difficult to accumulation of heat.The high speed excellent in te pins of durability of this tire 62.Less thickness t can contribute to lightweight.In this tire 62, also lightweight can be realized.And less quality can contribute to the reduction of rolling resistance.According to this viewpoint, preferably this thickness t is below 1.5mm.Because this thickness t is more little more preferred, therefore, this thickness t can be set as 0.0mm.In this case, enhancement Layer 84 exposes in the bottom of band ditch 94.

In this tire 62, enhancement Layer 84 is formed by the rubber composition comprising base rubber and chopped fiber.In other words, this enhancement Layer 84 is made up of many chopped fibers and matrix.These chopped fibers disperse in matrix.In this enhancement Layer 84, chopped fiber is orientation in the circumferential.Chopped fiber can contribute to the intensity of enhancement Layer 84 effectively.Rubber composition for this enhancement Layer 84 is identical with the rubber composition of the enhancement Layer 22 for the tire 2 shown in Fig. 1.

In this tire 62, enhancement Layer 84 comprises chopped fiber, and this chopped fiber orientation in the circumferential.In this tire 62, enhancement Layer 84 is laminated in string course 78.In this tire 62, enhancement Layer 84 and string course 78 move forward into row constraint together to bracing ply 76.In this tire 62, restrained effectively the protuberance of bracing ply 76.Further, because the thickness t of the tyre surface 64 at the bottom place of band ditch 94 is set as below 2.0mm, therefore, the part of the tyre surface 64 of this tire 62 is difficult to accumulation of heat.In this tire 62, by the synergistic effect of less thickness t and enhancement Layer 84, achieve the raising of high speed durability.

As mentioned above, enhancement Layer 84 is positioned at the radially inner side of band ditch 94.In this tire 62, because enhancement Layer 84 comprises chopped fiber, and this chopped fiber orientation in the circumferential, therefore, inhibit the generation in the crack at the bottom place of band ditch 94.Even if generation crack, this enhancement Layer 84 also can suppress the development in this crack.In this tire 62, although adopt less thickness t, also can prevent the generation of tyre surface ditch crackle (TGC).

In this tire 62, the thickness tf of preferred enhancement Layer 84 is more than 0.3mm below 3.0mm.By this thickness tf is set as more than 0.3mm, make enhancement Layer 84 effectively can contribute to the rigidity of tire 62.In this tire 62, both prevent the generation of TGC, achieve again the raising of high speed durability.According to this viewpoint, more preferably this thickness tf is more than 0.5mm.By this thickness tf is set as below 3.0mm, inhibit enhancement Layer 84 on the impact of the rigidity of tire 62.Because the quality of tire 62 is suitably maintained, therefore, the increase of rolling resistance can be prevented.According to this viewpoint, more preferably this thickness tf is below 2.0mm.

In this tire 62, the proportional quantity of the chopped fiber comprised in the rubber composition of enhancement Layer 84 is below more than 1 mass parts 100 mass parts relative to the base rubber of 100 mass parts.By the proportional quantity of this chopped fiber is set as more than 1 mass parts, enhancement Layer 84 is made to have the intensity of appropriateness.This enhancement Layer 84 can contribute to preventing the generation of TGC and the raising of high speed durability.According to this viewpoint, preferably the proportional quantity of this chopped fiber is more than 2 mass parts.By the proportional quantity of chopped fiber is set as below 100 mass parts, chopped fiber can fully be engaged with the rubber existed around this chopped fiber.The excellent in te pins of durability of this tire 62.According to this viewpoint, preferably the proportional quantity of this chopped fiber is below 90 mass parts.

In this tire 62, the average length L of chopped fiber is more than 1 μm less than 100 μm.By average length L is set as more than 1 μm, in enhancement Layer 84, the orientation in the circumference of chopped fiber can be realized.This enhancement Layer 84 can contribute to preventing the generation of TGC and the raising of high speed durability.According to this viewpoint, preferably this average length L is more than 5 μm.By average length L is set as less than 100 μm, chopped fiber can be made to disperse well in matrix, and chopped fiber can also be made fully to engage with the rubber existed around this chopped fiber.The excellent in te pins of durability of this tire 62.According to this viewpoint, preferred average length L is less than 90 μm.

[embodiment]

Below, show effect of the present invention by embodiment, but, determinate explanation should do not carried out based on the record of embodiment to the present invention.

[embodiment 1]

Obtain and possess the basic structure shown in Fig. 1 and the air-inflation tyre possessing the embodiment 1 of the specification shown in following table 1.The size of tire is set to 195/65R15.The material of the cord comprised in the bracing ply of the present embodiment 1 is steel.In the present embodiment 1, string course is not set.

A pair enhancement Layer is provided with in the tire of the present embodiment 1.Each enhancement Layer is configured at shoulder zone." type " in table hurdle, utilizes " part " to represent this.The chopped fiber coordinating and be made up of nylon fiber is added in enhancement Layer.The proportional quantity of chopped fiber is set to 10 mass parts relative to the base rubber of 100 mass parts.The average length L of chopped fiber is set to 10 μm.The thickness tf of enhancement Layer is set to 1.0mm.Thickness t from the bottom of band ditch to enhancement Layer is set to 1.0mm.Therefore, the thickness tb from the bottom of band ditch to bracing ply is 2.0mm.

Enhancement Layer in the present embodiment 1 is by being formed the roll of strip coiled be made up of the rubber composition being used for enhancement Layer in the circumferential." operation " in table hurdle, utilizes " new " to represent this.Enhancement Layer is formed in the mode of chopped fiber orientation in the circumferential." orientation " in table hurdle, utilizes " Y " to represent this.

[comparative example 1-2 and 5]

Except not arranging except enhancement Layer, all the other are all identical with embodiment 1, obtain the tire of comparative example 1-2 and 5 thus.As described in Table 1, in comparative example 1, thickness t is set to 2.0mm.In comparative example 2, thickness t is set as 3.0mm, and is provided with string course.This string course comprises the cord be made up of nylon fiber." string course " in table hurdle, utilizes " N-FB " to represent this.As shown in the following Table 3, in comparative example 5, thickness t is set to 1.0mm.

[comparative example 3]

Regulate the extrusion condition for the formation of band, not make the chopped fiber orientation in the circumferential comprised in enhancement Layer, in addition, all the other are all identical with embodiment 1, obtain the tire of comparative example 3 thus.For chopped fiber not orientation this point in the circumferential, " orientation " in table hurdle, is represented by " N ".

[embodiment 2-5 and comparative example 4]

Set thickness t and thickness tb as with following table 2, in addition, all the other are all identical with embodiment 1, obtain the tire of embodiment 2-5 and comparative example 4 thus.

[embodiment 6-9]

Set thickness tf and thickness tb as with following table 3, in addition, all the other are all identical with embodiment 1, obtain the tire of embodiment 6-9 thus.

[embodiment 10-12 and comparative example 6-7]

As set proportional quantity with following table 4, in addition, all the other are all identical with embodiment 1, obtain the tire of embodiment 10-12 and comparative example 6-7 thus.

[embodiment 13-14 and comparative example 8-9]

As set length L with following table 5, in addition, all the other are all identical with embodiment 1, obtain the tire of embodiment 13-14 and comparative example 8-9 thus.

[embodiment 15]

Except being configured to bracing ply entirety to be covered except this point by one deck enhancement Layer, all the other are all identical with embodiment 1, obtain the tire of embodiment 15 thus.For by one deck enhancement Layer, bracing ply entirety is covered this point, " type " in table hurdle, is represented by " all ".

[embodiment 16-17]

By reeling to a sheet material and making one end of this sheet material engage with its other end and form enhancement Layer, in addition, all the other are all identical with embodiment 1, obtain the tire of embodiment 16-17 thus.For utilizing existing manufacture method to manufacture tire this point, " operation " in table hurdle, is represented by " old ".In addition, in embodiment 16, the proportional quantity of chopped fiber is set as 2 mass parts.

[embodiment 18]

Obtain possessing the basic structure shown in Fig. 7 and possess with the air-inflation tyre of the embodiment 18 of the specification shown in following table 7.Tire is of a size of 195/65R15.The material of the cord comprised in the bracing ply of the present embodiment 18 is set to steel.String course is provided with in the present embodiment 18.This string course comprises the cord be made up of nylon fiber." string course " in table hurdle, utilizes " N-FB " to represent this.

In the tire of the present embodiment 18, identical with embodiment 1, be provided with a pair enhancement Layer.Each enhancement Layer is configured at shoulder zone." type " in table hurdle, utilizes " part " to represent this.The chopped fiber coordinating and be made up of nylon fiber is added in enhancement Layer.The proportional quantity of chopped fiber is set to 10 mass parts relative to the base rubber of 100 mass parts.The average length L of chopped fiber is set to 10 μm.The thickness tf of enhancement Layer is set to 2.0mm.Thickness t from the bottom of band ditch to enhancement Layer is set to 1.0mm.Therefore, the thickness tb from the bottom of band ditch to bracing ply is 3.0mm.

The enhancement Layer of the present embodiment 18 is by being formed the roll of strip coiled be made up of the rubber composition being used for enhancement Layer in the circumferential." operation " in table hurdle, utilizes " new " to represent this.Enhancement Layer is formed in the mode of chopped fiber orientation in the circumferential." orientation " in table hurdle, utilizes " Y " to represent this.

[comparative example 10-12 and 15]

Except not arranging except enhancement Layer, all the other are all identical with embodiment 18, obtain the tire of comparative example 10-12 and 15 thus.As shown in the following Table 7, in comparative example 10, thickness t is set to 2.5mm.In comparative example 11, thickness t is set to 3.0mm.In comparative example 12, thickness t is set as 4.0mm, and string course is set to 2 layers." string course " in table hurdle, utilizes " N-2FB " to represent this.As shown in the following Table 9, in comparative example 15, thickness t is set to 2.0mm.

[comparative example 13]

Regulate the extrusion condition for the formation of band, not make the chopped fiber orientation in the circumferential comprised in enhancement Layer, in addition, all the other are all identical with embodiment 18, obtain the tire of comparative example 13 thus.For chopped fiber not orientation this point in the circumferential, " orientation " in table hurdle, is represented by " N ".

[embodiment 19-22 and comparative example 14]

Set thickness t and thickness tb as with following table 8, in addition, all the other are all identical with embodiment 18, obtain the tire of embodiment 19-22 and comparative example 14 thus.

[embodiment 23-26]

Set thickness tf and thickness tb as with following table 9, in addition, all the other are all identical with embodiment 18, obtain the tire of embodiment 23-26 thus.

[embodiment 27]

As set proportional quantity with following table 10, all the other are all identical with embodiment 18, obtain the tire of embodiment 27 thus.

[embodiment 28]

Except being configured to bracing ply entirety to be covered except this point by one deck enhancement Layer, all the other are all identical with embodiment 18, obtain the tire of embodiment 28 thus.For by one deck enhancement Layer, bracing ply entirety is covered this point, " type " in table hurdle, is represented by " all ".In the present embodiment 28, the basic unit of tyre surface is made up of enhancement Layer.

[high speed durability]

According to ECE30 specification, high speed durability is evaluated.Know and made to manufacture experimently the speed V (km/h) that tire produces damage.In with following table 1 to 10, its result is shown.In the tire of embodiment 1-17 and comparative example 1-9, do not find damage when speed (speed represented by symbol " H " under being equivalent to JATMA specification) of 210km/h, this situation is set to qualified " OK ".For the situation finding damage at these H shelves (range), be set to nonconformity " NG ".In the tire of embodiment 18-28 and comparative example 10-15, do not find damage when speed (speed represented by symbol " V " under being equivalent to JATMA specification) of 240km/h, this situation is set to qualified " OK ".Find that the situation of damage is set to nonconformity " NG " at these V shelves.

[resistance to TGC]

Trial-production tire sets is loaded on regular wheel rim and makes it reach regular interior pressure, it is adjusted in temperature in the atmosphere of the ozone (concentration=50ppm) of 30 DEG C and places 3, then, the band ditch of this tire is observed, be confirmed whether to create tyre surface ditch crackle (TGC), and carry out the evaluation of grade.

A: free from flaw

B: there is the crack that several have the width less than 1mm and the length less than 1cm

C: there is the crack (cannot count) that many have the width less than 1mm and the length less than 1cm

D: there is the crack that many have the width of more than 1mm and the length of more than 1cm

E: there is the crack (cannot count) that many have the width of more than 1mm and the length of more than 1cm

In with following table 1 to 10, its result is shown." A " and " B " is qualified grade.

[rolling resistance]

Utilize rolling resistance test machine, and under following measuring condition, rolling resistance is measured.

Use wheel rim: 15 × 6-J (aluminum alloy)

Interior pressure: 200kPa

Load: 4.41kN

Speed: 50km/h

With in following table 1 to 10, comparative example 1 is set to the index of 100 to represent its result.Numerical value is the bigger the better.

[quality]

The quality of tire is measured.With in following table 1 to 10, comparative example 1 is set to the index of 100 to represent its result.Numerical value is the smaller the better.

[homogeneity]

According to the condition of the uniformity test of regulation in " JASO C607:2000 ", radial force variation (RFV) is measured.Be one group with 20 to measure each trial-production tire, obtain the aviation value of RFV thus.According to this aviation value, homogeneity is evaluated.With in following table 1 to 10, comparative example 1 is set to the index of 100 to represent its result.Numerical value is the bigger the better.

[manufacturing time]

Time needed for manufacture tire is measured.With in following table 1 to 10, comparative example 1 is set to the index of 100 to represent its result.Numerical value is the smaller the better.

Table 1 evaluation result

Table 2 evaluation result

Table 3 evaluation result

Table 4 evaluation result

Table 5 evaluation result

Table 6 evaluation result

Table 7 evaluation result

Table 8 evaluation result

Table 9 evaluation result

Table 10 evaluation result

As shown in table 1 to 10, compared with the tire of comparative example, for the having higher rating of tire of embodiment.According to this evaluation result, preceence of the present invention is obvious.

[utilizing possibility in industry]

Air-inflation tyre described above can be installed on various vehicle.

Claims (2)

1. an air-inflation tyre, wherein,

Described air-inflation tyre possesses:

Tyre surface, its outside face forms tread surface; Bracing ply, it is positioned at the radially inner side of described tyre surface; And enhancement Layer, it is between described tyre surface and described bracing ply,

Described bracing ply comprises and many cords of row arrangement, and each cord tilts relative to the equatorial plane,

Carve in the shoulder zone of described tread surface and be provided with the band ditch extended roughly vertically,

Described enhancement Layer is formed by rubber composition,

Described rubber composition comprises base rubber and chopped fiber,

The length of described chopped fiber is more than 1 μm less than 100 μm,

The proportional quantity of the described chopped fiber comprised in described rubber composition is below more than 1 mass parts 100 mass parts relative to the base rubber of 100 mass parts,

Described enhancement Layer is positioned at the radially inner side of described band ditch,

In described enhancement Layer, described chopped fiber orientation in the circumferential,

Thickness t from the bottom of described band ditch to described enhancement Layer is below 2.0mm.

2. air-inflation tyre according to claim 1, is characterized in that,

Described thickness t is below 1.5mm.