JP7135828B2 - Tire test method - Google Patents

Description

The present invention relates to a tire testing method. More particularly, the present invention relates to a tire testing method for evaluating adhesion of a noise damper to the inner surface of the tire body, in a tire having the noise damper attached to the inner surface of the tire body.

As a tire excellent in quietness, a tire provided with a sponge-like noise damper on the inner surface is known (for example, Patent Document 1). This tire is constructed by mounting a noise damper on the inner surface of the tire body.

The noise damper is usually attached to the inner surface of the tire body via an adhesive layer on the radially inner side of the tread. The adhesive layer includes, for example, double-sided adhesive tape, adhesive and viscous sealant.

Various evaluations are performed on this tire in order to confirm that there is no peeling or damage of the noise damper.

In the aforementioned Patent Document 1, a trial tire is left for 12 hours in a refrigerator whose internal temperature is set to −30° C. with 50 cc of water contained in the noise damper. After standing still, a running test of the prototype tire is performed on a drum running tester to confirm the occurrence of cracks in the noise dampers.

JP 2015-147544 A

Tires are mounted on rims. Surfactant is applied as a lubricant to the bead portion of the tire in order to increase the lubricity of the tire to the rim and facilitate assembly of the tire onto the rim. Some of the surfactant may adhere to the interior of the tire, in which case it is expected that the surfactant will come into contact with the dampener.

The inventors have evaluated a tire having a noise damper on its inner surface, and have found that some surfactants may alter the properties of the adhesive layer and the noise damper. Under such circumstances, establishment of a tire testing method capable of evaluating the influence of a surfactant on the adhesion of a noise damper to the inner surface of a tire body is desired.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a tire testing method capable of evaluating the influence of a surfactant on the adhesion of a noise damper to the inner surface of a tire body. and

A preferred tire testing method according to the present invention is a tire comprising a tire body and a noise damper attached to the inner surface of the tire body, for evaluating the adhesion of the noise damper to the inner surface of the tire body. is a tire test method. This test method is
(1) a preparation step of injecting a test liquid containing a surfactant into the lumen of the tire;
(2) A running step of applying a predetermined load to the tire having the noise damper containing the surfactant and running the tire at a predetermined speed.

Preferably, in this tire testing method, in the preparatory step, the test liquid is applied to the noise damper, or the test liquid is absorbed by the noise damper so that the surfactant is absorbed into the damper. included in musical instruments.

Preferably, in this tire testing method, the amount of surfactant included in the noise damper in the preparation step is at most 100 g.

Preferably, in this tire testing method, the surfactant is a surfactant used to increase the lubricity of the tire to the rim on which it is mounted. More preferably, in this tire test method, the surfactant is a metal salt of a fatty acid.

Preferably, in this tire testing method, the load applied to the tire in the running step is 70% or more and 150% or less of the normal load.

Preferably, in this tire testing method, the internal pressure of the tire is 70% or more and 130% or less of a normal internal pressure in the running step.

Preferably, in this tire testing method, the speed of the tire is 80 km/h or more and 120 km/h or less in the running step.

Preferably, in this tire testing method, projections are provided on the road surface on which the tire runs in the running step.

In the tire testing method according to the present invention, thermal fatigue and mechanical fatigue during running are reproduced in a tire containing a noise damper containing a surfactant. In this test method, the noise damper and the interface between the noise damper and the inner surface of the tire body are subjected not only to the chemical action of the surfactant, but also to the combined effects of heat and mechanical action. affected. This combined action promotes delamination and deterioration of the noise damper. This test method can evaluate the effect of surfactants on the adhesion of the noise damper to the inner surface of the tire body.

FIG. 1 is a cross-sectional view showing an example of a pneumatic tire used in a test method according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of the tire of FIG. 1 along the equatorial plane of this tire. FIG. 3 is a perspective view schematically showing an example of a testing apparatus used in a tire testing method. FIG. 4 is a perspective view schematically showing a modification of the testing device shown in FIG. 3;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

In the present invention, a state in which the tire is mounted on a normal rim, the internal pressure of the tire is adjusted to the normal internal pressure, and no load is applied to the tire is referred to as a normal state. In the present invention, the dimensions and angles of the tire and each portion of the tire are measured under normal conditions unless otherwise specified.

In the present invention, the regular rim means a rim defined in the standard on which the tire relies. A "standard rim" in the JATMA standard, a "design rim" in the TRA standard, and a "measuring rim" in the ETRTO standard are regular rims.

In the present invention, the normal internal pressure means the internal pressure defined in the standard on which the tire relies. The "maximum air pressure" in JATMA standards, the "maximum value" in "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in TRA standards, and the "INFLATION PRESSURE" in ETRTO standards are regular internal pressures.

In the present invention, the normal load means the load defined in the standard on which the tire relies. "Maximum load capacity" in the JATMA standard, "maximum value" in "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the TRA standard, and "LOAD CAPACITY" in the ETRTO standard are normal loads.

[tire]
FIG. 1 shows an example of a pneumatic tire 2 (hereinafter sometimes simply referred to as "tire 2") used in the test method according to the embodiment of the present invention. This tire 2 is mounted on a passenger car.

FIG. 1 shows part of a cross-section of this tire 2 along a plane containing the axis of rotation of the tire 2 . In FIG. 1 , the vertical direction is the radial direction of the tire 2 , the horizontal direction is the axial direction of the tire 2 , and the direction perpendicular to the paper surface is the circumferential direction of the tire 2 . In FIG. 1 , the dashed-dotted line CL is the equatorial plane of the tire 2 .

In FIG. 1, the tire 2 is mounted on the rim R. The inside of the tire 2 is filled with air, and the internal pressure of the tire 2 is adjusted to a normal internal pressure. In FIG. 1, the tire 2 is not loaded.

The tire 2 includes a tire body 4 and a noise damper 6 attached to the inner surface of the tire body 4. - 特許庁In the present invention, an uncrosslinked tire (not shown), that is, a tire 2 obtained by pressurizing and heating a raw tire in a mold (not shown) is represented as a tire body 4 .

A tire body 4 of this tire 2 includes a tread 8, a pair of sidewalls 10, a pair of beads 12, a carcass 14, an inner liner 16 and a belt 18.

The tread 8 is made of cross-linked rubber considering abrasion resistance and grip performance. The outer peripheral surface of the tread 8 is the tread surface 20 . The tire 2 contacts the road surface on the tread surface 20 . Grooves 22 are cut in the tread surface 20 .

Each sidewall 10 extends radially inward along the carcass 14 from the edge of the tread 8 . The sidewall 10 is made of crosslinked rubber in consideration of cut resistance.

Each bead 12 is positioned radially inward of the sidewall 10 . Bead 12 comprises core 24 and apex 26 . Core 24 includes steel wire. In the cross-section of tire 2 shown in FIG. 1, apex 26 tapers radially outward. Apex 26 is made of crosslinked rubber with high rigidity. In this tire 2, the portion of the bead 12 is fitted to the rim R.

A carcass 14 is located inside the tread 8 and the pair of sidewalls 10 . A carcass 14 extends from one bead 12 toward the other bead 12 . Carcass 14 includes at least one carcass ply 28 . The carcass 14 of this tire 2 is composed of one carcass ply 28 . The carcass 14 of this tire 2 has a radial structure.

Although not shown, the carcass ply 28 includes a large number of parallel carcass cords. In this tire 2, cords made of organic fibers are used as carcass cords. The organic fibers include nylon fibers, polyester fibers, rayon fibers and aramid fibers.

The inner liner 16 is positioned inside the carcass 14 . The inner liner 16 constitutes the inner surface of the tire body 4 . This inner liner 16 is made of a crosslinked rubber having excellent air shielding properties.

The belt 18 is laminated with the carcass 14 on the radially inner side of the tread 8 . Belt 18 comprises an inner layer 30 and an outer layer 32 . The width of the outer layer 32 is narrower than the width of the inner layer 30 . Although not shown, each of the inner layer 30 and the outer layer 32 includes a number of belt cords arranged side by side. Each belt cord is inclined with respect to the equatorial plane. In this tire 2, the material of the belt cord is steel.

The noise damper 6 of the tire 2 is made of a sponge material having porous portions on its surface or inside. The sponge material is made of, for example, rubber or synthetic resin having open or closed cells. For the noise damper 6 of the tire 2, an open-cell sponge material made of polyurethane is used. The noise damper 6 absorbs vibration energy of the air inside the tire 2 through its porous portion. This reduces resonance vibration and reduces road noise.

In this tire 2 , the noise damper 6 is positioned radially inside the tread 8 . This noise damper 6 is arranged so as to straddle the equatorial plane.

In FIG. 1, a double arrow Wa indicates the width of the noise damper 6 in the axial direction. A double arrow ta indicates the thickness of the noise damper 6 .

As shown in FIG. 1, the cross-sectional shape of the noise damper 6 is a horizontally long rectangular shape in which the width Wa of the noise damper 6 is greater than its thickness ta. In this tire 2, the thickness ta of the noise damper 6 is preferably 0.1 to 0.5 times its width Wa.

The cross-sectional shape of the noise damper 6 is not limited to a rectangular shape. Various cross-sectional shapes such as trapezoidal, triangular, warhead, and semicircular shapes are employed for the cross-sectional shape of the noise damper 6 . The noise damper 6 is preferably configured such that its cross-sectional shape is symmetrical with respect to the equatorial plane.

In the tire 2, the width Wa of the noise damper 6 is preferably 30% to 70% of the contact width TW of the tread 8 from the viewpoint of effectively reducing road noise, although not particularly limited. The thickness ta of the noise damper 6 is preferably 5-50 mm.

In the present invention, the contact width TW of the tread 8 is based on the contact patch obtained when the tire 2 in a normal state is applied with a normal load and is grounded on a flat road surface with a camber angle of 0 degrees. identified. The ground contact width TW of the tread 8 is represented by the axial distance from one axial outer end Te of the ground contact surface to the other axial outer end Te.

FIG. 2 shows a cross-section of this tire 2 along its equatorial plane. The direction perpendicular to this paper is the axial direction of this tire 2 .

In this tire 2, the noise damper 6 extends in the circumferential direction. As shown in FIG. 2, in this tire 2, one end surface 34 of the noise damper 6 is arranged apart from the other end surface 34 in the circumferential direction. In this tire 2, one end face 34 and the other end face 34 of this noise damper 6 may be spliced together.

In this tire 2 , the noise damper 6 is adhered to the inner surface of the tire body 4 via the adhesive layer 36 on the radially inner side of the tread 8 . The adhesive layer 36 includes, for example, a double-sided adhesive tape, an adhesive and a viscous sealant.

Although not shown, as the double-sided adhesive tape, a tape having adhesive layers provided on both sides of a flexible base sheet or a tape having only an adhesive layer without a base sheet can be used.

As the base sheet, for example, a woven fabric, a nonwoven fabric, a cotton fabric, a plastic film such as polyester, or a plastic foam sheet such as acrylic foam is preferably used. For the adhesive layer, for example, rubber-based adhesives obtained by mixing known additives such as tackifiers, softeners, anti-aging agents, etc. into natural rubber or synthetic rubber, multiple acrylic acid esters with different glass transition temperatures, and other types Acrylic pressure sensitive adhesives copolymerized with functional monomers (including high heat resistance, flame retardant, and low temperature adhesive types), silicone pressure sensitive adhesives composed of silicone rubber and resin, or polyether or polyurethane pressure sensitive adhesives etc. are preferably used.

Although not shown, various viscous sealing agents can be used as the viscous sealing agent, and for example, those that are substantially liquid at room temperature (20° C.) are preferably employed. In particular, in a temperature range of −20° C. to 60° C., a sealing agent that can penetrate into nail holes and the like to seal the nail holes and prevent leakage of tire internal pressure is preferably employed.

This viscous sealant preferably contains 30 parts by mass or more and 50 parts by mass or less of polybutene with respect to 100 parts by mass of the viscous sealant. Polybutene is a viscous liquid polymer obtained by cationic polymerization of isobutene and normal butene. It has excellent adhesiveness, does not change in adhesiveness or viscosity even after long-term use, and can be solidified and dried. Nor. Polybutene is particularly preferable because it is stable against heat and pressure and can stably maintain viscosity and adhesiveness from the beginning to the end of use of the tire.

In this viscous sealant, unvulcanized butyl rubber may be blended with the aforementioned polybutene in order to further improve the adhesiveness and sealing performance. In this case, the compounding ratio of butyl rubber and polybutene is preferably in the range of 40:60 to 60:40. Furthermore, white fillers and zinc oxide, for example, may be added to this viscous sealant in order to adjust the viscosity and workability.

[Test equipment]
FIG. 3 shows an example of a testing device 38 used in the testing method according to the embodiment of the invention. In this testing method, a running test of the tire 2 is performed using the testing device 38 shown in FIG. This test device 38 comprises a drive drum 40 and a support device 42 . In this testing device 38 , a drive drum 40 and a support device 42 are mounted on a pedestal 44 .

The drive drum 40 is rotatably supported by a pedestal 44 . The drive drum 40 is rotated by drive means (not shown). An electric motor is mentioned as a drive means. In this testing device 38 , the tire 2 runs on the peripheral surface of this driving drum 40 . In this test device 38, the peripheral surface of the driving drum 40 is the road surface 46. As shown in FIG. The diameter of the drive drum 40 is appropriately set within the range of 1.0 m to 2.0 m.

The support device 42 has a rim R and a rotating shaft 48 . A tire 2 is fitted to the rim R. The rim R is supported on the rotating shaft 48. As shown in FIG. The rotary shaft 48 is rotatably supported by the support device 42 by bearings (not shown).

In this test device 38, the rim R is for testing. This rim R corresponds to a regular rim. As long as this test device 38 can be attached to the support device 42, it is possible to use, as the rim R, a regular rim, an "acceptable rim" in the JATMA standard, and an "approved rim" in the TRA or ETRTO standard. .

Although not shown, the support device 42 further includes a rotation drive mechanism and a brake mechanism. The supporting device 42 can make the rotating shaft 48 rotatable, rotate the rotating shaft 48 independently of the drive drum 40 , and restrain the rotating shaft 48 . In this test device 38, the tire 2 mounted on the rim R can be accelerated, decelerated and stopped.

This support device 42 is provided with a lifting device (not shown) such as a hydraulic cylinder. The lifting device adjusts the position of the tire 2 with respect to the drive drum 40 . This adjustment brings the tire 2 into contact with the road surface 46 . A predetermined load is applied to the tire 2 by pressing the tire 2 against the road surface 46 . In this testing device 38 , the rotating shaft 48 of the supporting device 42 is rotatable, and the driving drum 40 is rotated while a predetermined load is applied to the tire 2 . As a result, the tire 2 runs on the road surface 46 of the driving drum 40 . Although not shown, the supporting device 42 is further provided with angle adjusting means for adjusting the angle of the rotating shaft 48 with respect to the driving drum 40 . In this test device 38, the camber angle of the tire 2 is adjusted by this angle adjusting means.

[Test method]
Next, a test method according to an embodiment of the present invention will be described. This test method includes a preparation step and a running step.

In the preparation step, a test liquid containing a surfactant is prepared. If the surfactant is liquid at normal temperature, this test method can use the surfactant as it is as the test liquid. A solution obtained by diluting the surfactant with a solvent may be used as the test liquid. If this surfactant is solid at room temperature, a solution obtained by dissolving this surfactant in a solvent such as water may be used as the test solution.

Various surfactants can be used as the surfactant in this test method. In this test method, neutral surfactants and alkaline surfactants are preferred as surfactants. Neutral surfactants include, for example, sulfonates. Examples of alkaline surfactants include fatty acid salts. In this test method, the surfactant used to increase the lubricity of the tire 2 with respect to the rim R when the tire 2 is incorporated into the rim R is more preferable as the surfactant.

In this preparatory step, the test liquid containing the aforementioned surfactant is injected into the inner cavity of the tire 2 . This allows the surfactant to be included in the noise damper 6 . In this test method, for example, a brush 50 may be used to apply the test liquid to the surface of the noise damper 6, as shown in FIG. Although not shown, this test method may be carried out by dripping the test liquid onto the noise damper 6 using a dropper or the like, so that the noise damper 6 absorbs the test liquid. In this preparatory step, preferably, a test liquid containing a surfactant is applied to the noise damper 6, or the test liquid is absorbed by the noise damper 6 so that the surfactant is absorbed into the noise damper 6. be included.

In this preparatory step, the tire 2 is mounted on the rim R after the noise damper 6 is impregnated with a surfactant. Air is filled inside the tire 2 and the internal pressure of the tire 2 is adjusted. After adjusting the internal pressure, the tire 2 assembled on the rim R (hereinafter also referred to as a tire-rim assembly) is attached to the rotating shaft 48 of the testing device 38 . The tire 2 is pressed against the road surface 46 by adjusting the position of the rotary shaft 48 of the driving drum 40 with respect to the road surface 46 . Thus, preparation of the tire 2 is completed. In this test method, the angle formed by the equatorial plane with respect to the normal to the road surface 46, specifically, the camber angle is set to 0 degree.

In this test method, the preparation process is followed by the running process. In this running process, the drive drum 40 is rotated to start running the tire 2 . In this running process, a predetermined load is applied to the tire 2 in which the noise damper 6 contains the surfactant, and the tire 2 is run at a predetermined speed.

In this test method, the tire 2 is stopped when the running distance of the tire 2 reaches a predetermined distance. The tire 2 is removed from the rim R, and the condition (peeling or deterioration) of the noise damper 6 or the like is checked. At this point, the evaluation may be terminated, but in this test method, the tire 2 is stopped, removed from the rim R, and the condition of the noise damper 6, etc. is checked every predetermined running distance. may be confirmed. In this case, before the tire 2 is assembled on the rim R again, the noise damper 6 may be coated with or absorbed with the test liquid so that the noise damper further contains a surfactant. This test method can be configured appropriately according to the contents to be evaluated.

In this test method, thermal fatigue and mechanical fatigue during running are reproduced in the tire 2 in which the noise damper 6 contains the surfactant. In this test method, the noise damper 6 and the boundary portion between the noise damper 6 and the inner surface of the tire body 4 were subjected to not only the chemical action of the surfactant but also the thermal action and mechanical action. compounded. This combined action promotes peeling and deterioration of the noise damper 6 . This test method can evaluate the effect of surfactants on the adhesion of the noise damper 6 to the inner surface of the tire body 4 .

As described above, in this test method, the surfactant can be used as it is as the test liquid, or a solution obtained by diluting the surfactant with a solvent can be used as the test liquid. In this test method, the amount of surfactant contained in the test liquid can be adjusted. Therefore, in this test method, a test liquid containing a high concentration of surfactant is mainly included in the vicinity of the end face 34 of the noise damper 6, so that the surface active agent can be applied to the noise damper 6 and the adhesive layer 36. Chemical effects can be evaluated. This test method can also evaluate the ease of peeling of the noise damper 6 from the inner surface of the tire body 4 by soaking the entire noise damper 6 in a test liquid containing a low-concentration surfactant.

In this test method, the maximum amount of surfactant included in the noise damper 6 is preferably 100 g in the preparatory step. By setting the amount of the surfactant to 100 g or less, the influence of the surfactant contained in the noise damper 6 on the mass balance of the tire 2 can be suppressed. Since the tire 2 can be run without generating vibration during the running process, this test method can properly evaluate the influence of the surfactant on the adhesion of the noise damper 6 to the inner surface of the tire body 4. can be done. From this point of view, the amount of surfactant contained in the noise damper 6 is more preferably 90 g or less.

As described above, in this test method, when the tire 2 is incorporated into the rim R, the surfactant used to increase the lubricity of the tire 2 with respect to the rim R may be used as the surfactant in this test method. preferable. Since the noise damper 6 and the adhesive layer 36 used to attach the noise damper 6 to the inner surface of the tire body 4 are likely to be degraded by an alkaline liquid, a metal salt of fatty acid is used as the surfactant. is preferred. From this point of view, in this test method, the metal salt of fatty acid is more preferably an alkali metal salt of fatty acid, that is, soap. Examples of the soap include alkali metal salts, more preferably sodium or potassium salts, of higher fatty acids having an average carbon number of 10 to 20, preferably 12 to 18 carbon atoms. A particularly preferred metal salt of a fatty acid is sodium stearate. In this test method, soap, specifically sodium stearate, works particularly effectively as a surfactant when the noise damper 6 of the tire 2 is made of polyurethane.

In this test method, the load applied to the tire 2 in the running process is preferably 70% or more and preferably 150% or less of the normal load. As a result, this test method not only chemically affects the noise damper 6 and the boundary between the noise damper 6 and the inner surface of the tire body 4, but also thermally and mechanically. can exert a sufficient effect. This test method can effectively evaluate the effect of surfactants on the adhesion of the noise damper 6 to the inner surface of the tire body 4 .

In this test method, the internal pressure of the tire 2 is preferably 70% or more and preferably 130% or less of the normal internal pressure in the running process. As a result, this test method not only chemically affects the noise damper 6 and the boundary between the noise damper 6 and the inner surface of the tire body 4, but also thermally and mechanically. can exert a sufficient effect. This test method can effectively evaluate the influence of the surfactant on the adhesion of the noise damper 6 to the inner surface of the tire body 4 .

In this test method, the speed of the tire 2 is preferably 80 km/h or more and preferably 120 km/h or less in the running process. As a result, this test method not only chemically affects the noise damper 6 and the boundary between the noise damper 6 and the inner surface of the tire body 4, but also thermally and mechanically. can exert a sufficient effect. This test method can effectively evaluate the effect of surfactants on the adhesion of the noise damper 6 to the inner surface of the tire body 4 .

FIG. 5 shows a modification of the testing device 38 used in the testing method of the present invention. As shown in FIG. 5, in this test method, slats 52 may be placed on the road surface 46 of the drive drum 40 . The slats 52 are plate-shaped and extend in the width direction of the road surface 46 , that is, in the axial direction of the drive drum 40 . The slats 52 contribute to improving the impact force acting on the tire 2 . In this test method, the noise damper 6 and the boundary portion between the noise damper 6 and the inner surface of the tire body 4 are subjected to not only the chemical action of the surfactant but also the thermal action and mechanical action. It can be fully exerted. This test method can more effectively evaluate the effect of the surfactant on the adhesion of the noise damper 6 to the inner surface of the tire body 4 .

In the test rig 38 shown in FIG. 5, one slat 52 is placed on the road surface 46 of the drive drum 40 . In this test method, a plurality of slats 52 may be spaced on the road surface 46 . In this case, the width of the slats 52 provided on the road surface 46 and the intervals between the slats 52 are appropriately determined in consideration of the impact force acting on the tire 2 .

In this test method, the height of the slats 52 is preferably 10 mm or more and preferably 50 mm or less. As a result, a sufficient impact can be applied to the tire 2 .

In this test method, the cross-sectional shape of the slats 52 is rectangular. In this test method, the cross-sectional shape of the slat 52 is not particularly limited as long as the impact force can be effectively applied to the tire 2 . The cross-sectional shape may be an isosceles triangle shape or an isosceles trapezoid shape instead of a rectangular shape. The cross-sectional shape may be semicircular.

As is clear from the above description, according to the present invention, a test method for the tire 2 is obtained that can evaluate the influence of the surfactant on the adhesion of the noise damper 6 to the inner surface of the tire body 4. .

The embodiments disclosed this time are illustrative in all respects and are not restrictive. The technical scope of the present invention is not limited to the above-described embodiments, but includes all modifications within the scope of equivalents to the configuration described in the claims.

The tire testing method described above is capable of evaluating various types of tires having noise dampers on their inner surface.

2 Tire 4 Tire body 6 Noise damper 8 Tread 10 Side wall 12 Bead 14 Carcass 16 Inner liner 18 Belt 34... End surface 36... Adhesive layer 38... Test device 40... Drive drum 42... Support device 46... Road surface 48... Rotating shaft 52... Slat

Claims (9)

A tire test method for evaluating the adhesion of the noise damper to the inner surface of the tire body in a tire comprising a tire body and a noise damper attached to the inner surface of the tire body,
A preparation step of injecting a test liquid containing a surfactant into the lumen of the tire;
and a running step of applying a predetermined load to the tire containing the surfactant in the noise damper and running the tire at a predetermined speed. 2. The surfactant is included in the noise damper in the preparation step by applying the test liquid to the noise damper or allowing the test liquid to be absorbed by the noise damper. Test method for tires described in . 3. A tire testing method according to claim 1 or 2, wherein in said preparatory step, the maximum amount of surfactant contained in said noise damper is 100g. A tire testing method according to any one of claims 1 to 3, wherein the surfactant is a surfactant used to increase the lubricity of the tire to the rim on which the tire is mounted. 5. The tire testing method of claim 4, wherein the surfactant is a metal salt of a fatty acid. The tire testing method according to any one of claims 1 to 5, wherein the load applied to the tire in the running step is 70% or more and 150% or less of the normal load. The tire testing method according to any one of claims 1 to 6, wherein in the running step, the internal pressure of the tire is 70% or more and 130% or less of a normal internal pressure. The tire testing method according to any one of claims 1 to 7, wherein in the running step, the speed of the tire is 80 km/h or more and 120 km/h or less. The tire testing method according to any one of claims 1 to 8, wherein in the running step, projections are provided on the road surface on which the tire runs.

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