JPH1111106A - Pneumatic tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight tubeless tire having no inner linear which is excellent in the bonding property between a low permeable case cord coating rubber layer and the other tire member mainly composed of diene rubber. SOLUTION: This tire has a case cord coating rubber layer having lines of case cords 4 in the inner part. The rubber composition for the case cord coating rubber layer contains 100 pts.wt. of a rubber component consisting of 50-90 wt.% of a diene rubber and 50-10 wt.% of a bromide of isobutylene/p- methylstyrene copolymer and 1-10 pts.wt. of a tackier, and contains no plasticizer. Thus, a tubeless pneumatic tire having no inner liner can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tubeless pneumatic tire without an inner liner.

[0002]

2. Description of the Related Art Conventionally, in a tubeless pneumatic tire, rubber having low air permeability such as butyl rubber has been used for an inner liner to maintain air pressure. FIG. 3 is a schematic cross-sectional view showing the vicinity of a case cord covering rubber layer of a typical conventional tubeless pneumatic tire.
In FIG. 3, reference numeral 1 denotes a case code covering rubber layer, in which case codes 4 are usually arranged in a line. An inner liner 7 made of butyl rubber or the like for maintaining air pressure is provided inside the tire, and a sidewall layer 8 is provided outside the tire. The inner liner occupies about 10% by weight of the members constituting the tire, which hinders the weight reduction of the tire.

On the other hand, tires are required to be reduced in weight based on the demand for low fuel consumption and simplification of the tire manufacturing process is required. For example, butyl rubber and isobutylene / p-methylstyrene copolymer having low air permeability are required. It has been proposed to prepare a tire case code covering rubber layer 1 with a rubber composition containing a compounded bromide and the like, and to omit the inner liner 7 (JP-A-6-55665, JP-A-6-156).
007, JP-A-8-157648).

[0004] However, highly saturated rubber such as butyl rubber is inferior in adhesion to diene rubber which is a highly unsaturated rubber.
Poor adhesion between the case cord coating rubber layer and other tire components containing diene rubber as the main component, such as sidewalls, and also poor adhesion with the case cord, resulting in poor tire durability was there.

For example, Japanese Unexamined Patent Publication No. Hei 8-157648 discloses that a rubber composition constituting a case cord coating rubber layer is made of isomono rubber as a highly saturated rubber in order to achieve both adhesion to a cord and low air permeability. It is disclosed that a bromide of an olefin / p-alkylstyrene copolymer is used.

However, in order to achieve the above-mentioned effect, the amount of the bromide must be actually increased to 50 parts by weight or more, and therefore, adhesion to another tire member containing a diene rubber as a main component is required. There is a problem that it is inferior.

[0007]

As described above, a case cord having low air permeability and having sufficient adhesiveness to both other tire members and cords containing diene rubber as a main component. No coated rubber layer was obtained.

That is, an object of the present invention is to provide a tubeless tire having no inner liner, which has excellent adhesion between a case cord covering rubber layer and a case cord and another tire member mainly composed of a diene rubber, and is durable. It is an object of the present invention to provide a lightweight tubeless pneumatic tire without a flexible inner liner.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a tubeless tire having a case cord covering rubber layer having a case cord row therein, wherein the rubber composition for the case cord covering rubber layer contains 50 to 90% by weight of a diene-based rubber composition. Rubber and 50
A tubeless pneumatic tube containing 100 to 10 parts by weight of a rubber component composed of brominated isobutylene / p-methylstyrene copolymer and 1 to 10 parts by weight of a tackifier and containing no plasticizer and without an inner liner. Regarding tires.

Further, the present invention relates to a tubeless tire having a case cord covering rubber layer having a case cord row inside, wherein the case cord covering rubber layer is formed from the case cord row to a case cord covering inner rubber layer of a tire inner portion and a case cord. An outer rubber layer of a case cord covering an outer portion of the tire from the row, wherein the inner rubber layer is 50 to 90% by weight of a diene rubber and 50 to 10% by weight of a bromide of isobutylene / p-methylstyrene copolymer. The present invention relates to a tubeless pneumatic tire without an inner liner, which comprises a rubber composition containing 100 parts by weight of a rubber component and 1 to 10 parts by weight of a tackifier and not containing a plasticizer.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention has a structure having no inner liner in FIG. 3 and has a rubber composition for a case cord covering rubber layer (hereinafter simply referred to as "rubber composition A"). A rubber component comprising 50 to 90% by weight of a diene rubber and 50 to 10% by weight of a bromide of isobutylene / p-methylstyrene copolymer.
It is characterized in that it contains parts by weight and 1 to 10 parts by weight of a tackifier and does not contain a plasticizer.

In general, rubber compositions for tires include mineral oil-based softeners such as mineral oil and aroma oil, vegetable softeners, and phthalic acid derivatives in order to improve processability, tackiness, flexibility and the like. However, as the amount of the plasticizer increases, the rubber composition has a problem that the rubber composition is inferior in adhesion to other tire members or case cords containing a diene rubber as a main component. Then, the present inventor decided not to use a plasticizer in the rubber composition for the case cord-covered rubber layer in the present invention.

Further, the present inventor has set forth that the rubber composition A is
By containing a bromide of isobutylene / p-methylstyrene copolymer, it has low air permeability, and in particular, by containing a specific amount of a tackifier, it is possible to maintain processability without containing a plasticizer, It has also been found that the tire has excellent adhesion to other tire members such as a sidewall (SW) layer mainly composed of a diene rubber and a case cord.

The diene rubber constituting the rubber composition A in the present invention may be any one which has been conventionally used in the field of tires, particularly a rubber layer coated with a case cord. For example, natural rubber, styrene butadiene rubber, Butadiene rubber, isoprene rubber, chloroprene rubber, acrylonitrile butadiene rubber and the like can be used, and these can be used alone or in any combination.However, natural rubber is mainly used in view of increasing the strength of the obtained rubber composition. Is preferred.

In the present invention, the rubber composition A contains a bromide of isobutylene / p-methylstyrene copolymer in order to obtain low air permeability. Conventionally, butyl rubber such as brominated butyl rubber, which is a highly saturated rubber, is used to impart low air permeability.However, these butyl rubbers have low air permeability similar to that of the above-mentioned copolymer bromide. However, the adhesiveness to diene rubber or cord is difficult, and the effect of the present invention is not exhibited.

The brominated isobutylene / p-methylstyrene copolymer is not particularly limited, but the isobutylene content is 89 to 97% by weight, preferably 89 to 95% by weight, particularly 89 to 95% by weight in view of adhesiveness. Preferably 8
It is preferably from 9 to 93% by weight.

Among the brominated isobutylene / p-methylstyrene copolymers that can be used in the present invention, commercially available products such as EXXPRO 90-10 and EXXPRO 8 manufactured by Exxon Chemical Co., Ltd.
9-4, EXXPRO 93-5 and the like.

The mixing ratio of the rubber component of the rubber composition A in the present invention is determined from the viewpoint of achieving a balance between low air permeability and adhesion to other tire members or case cords containing diene rubber as a main component. 50 to 90% by weight of a diene rubber, 50 to 10% by weight of a bromide of an isobutylene / p-methylstyrene copolymer, and further increase the adhesion to other tire members or case cords containing a diene rubber as a main component,
From the viewpoint of increasing the durability of the obtained tire, preferably 70 to 90% by weight of a diene rubber, isobutylene / p-
30 to 10% by weight of brominated methylstyrene copolymer,
Further, from the viewpoint of achieving both reduction in weight and low air permeability, it is particularly preferable to use 71 to 80% by weight of a diene rubber and a brominated product of an isobutylene / p-methylstyrene copolymer 29 to 2%.
0% by weight.

In the present invention, the rubber composition A
Is to improve the adhesiveness with other tire members and case cords containing a diene rubber as a main component, and also to improve the adhesiveness at the time of molding the tire, and to impart excellent low air permeability. Contains tackifier.

The tackifier may be any one used in the field of tires, such as coumarone resin, phenol resin, terpene resin, petroleum hydrocarbon resin, and rosin derivative. Or any combination thereof, but preferably phenolic resin, terpene resin, petroleum hydrocarbon resin in view of good adhesiveness, and particularly preferably petroleum hydrocarbon resin in terms of economy. .

Among the tackifiers that can be used in the present invention, commercially available tackifiers include, for example, Marcalez T100A (petroleum hydrocarbon resin) manufactured by Maruzen Petrochemical Co., Ltd., and Escolets 1102 (petroleum manufactured by Exxon Chemical) Hydrocarbon resin).

The mixing ratio of the tackifier in the rubber composition A is 1 to 100 parts by weight of the rubber component.
The amount is preferably from 10 to 10 parts by weight, but is preferably from 3 to 10% by weight from the viewpoint of tackiness, and more preferably from 3 to 8% by weight from the viewpoint of adhesiveness.

Further, the rubber composition A contains, as components other than the rubber component and the tackifier, fillers such as carbon black and silica, vulcanizing agents such as sulfur, and vulcanization aids such as stearic acid and zinc white. Vulcanization accelerators such as N-tert-butyl-2-benzothiazolylsulfenamide (NS), dibenzothiazyl sulfide (DM),
Compounding agents such as alkylphenol disulfide, 2,5-dimercapto-1,3,4-thiadiazole, and 2-di-n-butylamino-4,6-dimercapto-S-triazine can be used to lower the rubber layer of the case code. You may mix suitably as long as air permeability and the adhesiveness with another tire member or case cord are not spoiled.

In particular, when carbon black is blended, the HAF grade rubber should be blended in an amount of not more than 65 parts by weight with respect to 100 parts by weight of the rubber component from the viewpoint that the hardness of the obtained rubber composition is not excessively increased. However, from the viewpoint of increasing low air permeability, 35 to 65 parts by weight are preferably blended.

The case cord to be coated with the rubber composition A may be any cord that has been conventionally used in the field of tires. For example, organic fibers such as rayon, nylon, tetron (polyester) and Kevlar , Glass fiber, steel wire, etc., but from the viewpoint of adhesion to the rubber composition A, durability of the obtained tire, and reduction in weight, it is preferable to use organic fibers, and in particular, use polyester. Is particularly preferred.

The method of coating the cord with the rubber composition A to obtain a case cord-covered rubber layer may be a conventional method. For example, the cord is sandwiched between two rubber sheets obtained from the rubber composition A. , Extruded with a roll and coated (rubberized). Otherwise, the tubeless tire without the inner liner of the present invention can be obtained by the method and conditions in the conventional tire production.

In the present invention, the tire member containing a diene rubber as a main component includes, for example, a tread portion and a belt in addition to the sidewall portion.

There is no particular limitation on the rubber component constituting the tire member containing the diene rubber as a main component, as long as it is a conventional rubber component containing the diene rubber as a main component. Examples include diene rubbers such as rubber, styrene butadiene rubber, and butadiene rubber, and may include EPDM, butyl rubber, and the like.

According to the first embodiment of the present invention, by adopting the above configuration, the case cord covering rubber layer itself is provided with low air permeability, and a tread rubber containing a diene rubber as a main component. Adhesion with other tire members such as sidewall rubber and the case cord can be made sufficient. As a result, a lightweight and durable tubeless pneumatic tire without an inner liner can be obtained.

Next, a second embodiment of the present invention will be described.

Usually, as described above, the case cord-covered rubber layer is produced by sandwiching the cord between two rubber sheets made of the rubber composition for the case cord-covered rubber layer, extruding with a roll, and rubberizing. Therefore, as shown in the schematic cross-sectional view of FIG. 1, the case cord covering rubber layer 1 includes a case cord 4 and a case cord covering inner rubber layer (hereinafter, also referred to as an “inner rubber layer”) of a tire inside portion from the case cord row. It can be said that the outer rubber layer 2 comprises two rubber layers, that is, an outer rubber layer (hereinafter, also referred to as an “outer rubber layer”) 3 on the outer side of the tire from the case code row.

Therefore, a second embodiment of the present invention is a tubeless pneumatic tire without an inner liner, wherein the rubber composition for the inner rubber layer covered with the case cord comprises the rubber composition A.

That is, in the second embodiment of the present invention, in the case cord-covered rubber layer of two layers shown in FIG. 1, the case cord-covered inner rubber layer is provided with low air permeability and adhesiveness to the cord. And the rubber composition A
Is used.

In this case, the rubber composition (hereinafter, referred to as “rubber composition B”) constituting the case cord-coated outer rubber layer (hereinafter, also referred to as “outer rubber layer”) constitutes the inner rubber layer. The rubber composition has good adhesion to other tire members (for example, sidewall portions) mainly containing the rubber composition A, cord and diene rubber.

Accordingly, the rubber composition B may have the same constitution as the rubber composition A, but the bromine content of the isobutylene / p-methylstyrene copolymer may be smaller than that of the rubber composition A. .

The rubber composition B is characterized in that the inner rubber layer has an inner rubber layer, cord and adhesiveness to other tire members mainly composed of diene rubber, and low air permeability. From the viewpoint, a conventional rubber composition for covering a case cord in which the rubber component is composed of a diene rubber may be used. The rubber composition B is preferably composed of a rubber component composed of natural rubber and SBR, carbon black and a plasticizer, and if necessary, a vulcanizing agent such as sulfur, stearic acid, a vulcanizing aid such as zinc white, It may contain a vulcanization accelerator and the like.

When a tire is manufactured using this case cord-covered rubber layer, the schematic cross-sectional view of FIG. 2 is used in view of the adhesiveness to other tire members containing diene rubber as a main component. In addition, a layer (bead portion outer rubber layer) made of the same rubber composition as that constituting the case cord coating outer rubber layer 3 is provided on the tire outer portion where the case cord coating inner rubber layer 2 is rolled up from the bead 6. It may be provided.

According to the second embodiment of the present invention, by adopting the above-mentioned structure, low air permeability can be imparted to the inner rubber layer covered with the case cord. Thereby, a lightweight and durable tubeless pneumatic tire without an inner liner can be obtained.

[0039]

The present invention will be described below with reference to examples.
The present invention is not limited only to these.

Production Examples 1 to 8 As rubber compositions A for the case cord-coated rubber layer and the case cord-coated inner rubber layer, rubber compositions A-1 to A-8 having the compounding ratios shown in Table 1 were prepared. The mixture was kneaded with a rubber component and carbon black, and the resulting kneaded product was kneaded with sulfur, NS, zinc white, and stearic acid using a roll.

As the diene rubber, natural rubber (N
R) and a bromide of isobutylene / p-methylstyrene copolymer include EXXPRO 90 manufactured by Exxon Chemical Co., Ltd.
-10 (represented as “copolymer” in the table) (isobutylene content: 92.5% by weight), as carbon black, diamond black H manufactured by Mitsubishi Chemical Corporation as HAF class N330, tackifier As Maruzen Petrochemical Co., Ltd.
Marcalez T100A (petroleum hydrocarbon resin) was used. In addition, 2 parts by weight of stearic acid and insoluble sulfur (M95 manufactured by Nippon Kaizoku Co., Ltd.) were added to all rubber compositions.
75 parts by weight, 1 part by weight of N-tert-butyl-2-benzothiazolylsulfenamide (NS) (Noxeller NS manufactured by Ouchi Shinko Chemical Co., Ltd.) and 5 parts by weight of zinc white were mixed.

[Evaluation Method] Evaluation of Air Permeability The obtained rubber compositions A-1 to A-8 were cured with a hydraulic press at a vulcanization pressure of 9.8 MPa (100 kgf / cm ² ) at a vulcanization temperature of 170 ° C. In order to evaluate the air permeability of the vulcanized rubber compositions A-1 to A-8 vulcanized under the conditions of a vulcanization time of 12 minutes, according to the test method of ASTM D-1434-75M, Toyo Seiki Co., Ltd. Gas permeability measuring device M-C1
Was used to measure the air permeability coefficient. 1 of Comparative Example 1
It was shown as an index as 00. The smaller the value, the lower the air permeability. Table 1 shows the results.

Evaluation of adhesion between cord and rubber composition A About 48 polyester yarns (1670DT) per 5 cm
E × 2 (diameter 0.66 mm) is rubberized with rubber compositions A-1 to A-8 as the rubber composition A for the case cord-covered rubber layer, and a rubber sheet containing a textile cord (case-cord-covered rubber layer) A-1 to A-8 were obtained. The two rubber sheets obtained were overlapped so that the directions of the inner cords were perpendicular to each other, and a Mylar sheet was inserted between the rubber sheets and vulcanized and bonded at 150 ° C. for 30 minutes at a pressure of 9.8 MPa. The obtained adhesive strength measurement sample was subjected to a peel test at a test speed of 50 mm / min using a tensile tester to measure the adhesive (peel) strength (N / 25 mm). The results are shown in Table 1 as adhesiveness 1. 300N /
There is no problem if it is 25 mm or more.

Evaluation of Adhesiveness of Rubber Composition for Side Wall (SW) and Rubber Composition A From the rubber compositions A-1 to A-8 for the case cord-covered rubber layer, the thickness was determined using a roll at the stage of kneading rubber. 2mm thick sheet, cut to 2mm thickness, 80mm width, 150 length
mm rubber sheets A-1 to A-8 were obtained.

Next, as a rubber composition for another tire member (sidewall) containing a diene rubber as a main component, 40 parts by weight of natural rubber, 60 parts by weight of butadiene rubber, and carbon black (manufactured by Tokai Carbon Co., Ltd.) Seast SO: F
EF) 60 parts by weight, stearic acid 2 parts by weight, zinc white 2.
A rubber composition for SW comprising 5 parts by weight, 1.5 parts by weight of sulfur and 1 part by weight of NS was obtained in the same manner as the rubber composition A, and a rubber sheet for SW was obtained in the same manner as the rubber sheet A. Next, the rubber sheet A and the rubber sheet for SW were vulcanized and bonded under the conditions of a vulcanization pressure of 2 MPa, a vulcanization temperature of 170 ° C., and a vulcanization time of 12 minutes, and the obtained adhesive strength measurement sample was treated in the same manner as described above. The adhesive strength (kgf / 25 mm) was measured. The results are shown in Table 1 as Adhesion 2. 50 kg
There is no problem if f / 25 mm or more. 100k more
gf / 25 mm or more is particularly preferable.

Evaluation of Adhesion between Rubber Composition A as Case Cord-Coated Inner Rubber Layer and Rubber Composition for Case Cord-Coated Outer Rubber Layer, and Cords Rubber Composition for Case Cord-Coated Outer Rubber Layer with the Following Composition A rubber sheet (hereinafter, referred to as “outside rubber sheet”) made of (hereinafter, referred to as “outside rubber composition”) was obtained in the same manner as the rubber sheet A.

NR: 70 parts by weight SBR (SBR1502 manufactured by Nippon Synthetic Rubber Co., Ltd.): 3
0 parts by weight Carbon black (HAF N330): 45 parts by weight Plasticizer (mineral oil): 10 parts by weight Stearic acid: 2 parts by weight Zinc white flower: 5 parts by weight Insoluble sulfur: 3.75 parts by weight NS: 1 part by weight

Next, about 48 polyester yarns per 5 cm (1670 DTE × 2 (0.66 mm in diameter))
Is sandwiched between the rubber compositions A-1 to A-8 as the rubber composition for the case cord-covered inner rubber layer and the outer rubber sheet, and the rubber sheet with the textile cord (case cord-covered rubber layer) A -1 to A-8 were obtained. The two obtained rubber sheets are overlapped so that the directions of the inner cords are perpendicular to each other, and the outer rubber layer and the inner rubber layer are alternately inserted. Vulcanization bonding was performed at a pressure of 9.8 MPa for a minute. With respect to the obtained adhesive strength measurement sample, a peel test was performed at a test speed of 50 mm / min using a tensile tester, and the adhesive strength (N / 25 mm) was measured. The results are shown in Table 1 as adhesiveness 3. The higher the strength, the better, but there is no problem if the strength is 300 N / 25 mm or more.

Evaluation of moisture permeability Using the rubber sheet A, the moisture permeability of the rubber was measured based on the cup method of JIS Z 0208 and converted to a value of 1 mm in thickness. 10
0 and expressed as a relative value. Table 1 shows the results. The smaller the value, the lower the moisture permeability, and when the water present inside the obtained tire escapes to the outside, it is possible to prevent separation between breakers due to hydrolysis of the case cord and deterioration of the rubber covering the case cord. There is an advantage that you can.

[0050]

[Table 1]

Comparative Production Examples 1 to 14 Comparative rubber composition A and comparative rubber sheet A were obtained in the same manner as rubber composition A and rubber sheet A, except that the proportions shown in Table 2 were changed. Was performed. Table 2 shows the results.

In Table 2, Br-IIR2255 (brominated butyl rubber) manufactured by Exxon Chemical Co., Ltd. was used as Br-IIR, and mineral oil manufactured by Japan Energy Co., Ltd. was used as a plasticizer.

[0053]

[Table 2]

From the results shown in Tables 1 and 2, the blending ratio of the natural rubber and the bromide of isobutylene / p-methylbutylene copolymer was set to 50 to 90 parts by weight / 50 to 10 parts by weight, and no plasticizer was added. It has been found that all the properties of air permeability, moisture permeability and adhesiveness can be satisfied only by adding 5 to 10 parts by weight of the tackifier.
That is, the adhesiveness to the cord is not sufficient only with the brominated butyl rubber. When a plasticizer is added, not only the air permeability is lowered but also the adhesive strength is lowered.

Examples 1 to 4 In the first embodiment of the present invention, rubber compositions A-1, 4, 7, and 8 were used as the rubber composition A for the rubber layer coated with the case cord, and the others were obtained by a conventional method. Tubeless tires (tires 1-4) without an inner liner according to the invention having a size of 205 / 65R15 were prepared.

Comparative Example 1 A tubeless tire (Comparative Tire 1) was produced in the same manner as in Example 1 except that the outer rubber composition was used as the rubber composition for the case cord-covered rubber layer, and an inner liner was provided in a conventional manner. did.

Comparative Examples 2 to 7 Tubeless tires (Comparative tires) were prepared in the same manner as in Example 1 except that Comparative rubber compositions 1, 2, 6, 11, 13 and 14 were used as the rubber compositions for the case cord-coated rubber layer. 2 to 7) were produced.

Examples 5 to 8 In the second embodiment of the present invention, the above rubber composition A-1 was used as the rubber composition for the inner rubber layer covered with the case cord.
Except for using the outer rubber composition used in the evaluation of the above production example as the rubber composition for the case cord-coated outer rubber layer, the present invention has the same size as the tire 1 in the conventional method, except that the rubber compositions for the outer cord layer covered with the case cords To produce tubeless tires (tires 5 to 8) without an inner liner.

The obtained tires 1 to 8 and comparative tire 1
7 were measured, and rolling resistance, air permeability (air leak) and durability were measured in the following manner. Table 3 shows the results.

Note that the under-cord gauge in Table 3 refers to the thickness of rubber inside the tire below the case cord under the tread crown of the tire. In Comparative Example 1, the thickness is the thickness of the case cord covering rubber layer and the inner liner, and in other Comparative Examples and Examples, the thickness is the thickness of the case cord covering rubber layer.

[Evaluation method] Rolling resistance Using a drum tester, 80 km / h, load 400 kg
The measurement was performed under the condition of f, and the index for the comparative tire 1 was set to 100 and indicated by an index. The smaller the value, the lower the rolling resistance.

Air permeability (air leak) The obtained tire is assembled on a rim, and the internal pressure is set to 3 kgf / cm ^2.
The rate of decrease of the internal pressure after 3 months was measured, and the index for the comparative tire 1 was set to 100 and indicated as an index. The larger the value, the smaller the decrease rate.

Durability The obtained tire is assembled on a rim, and the running speed is 80 km / h.
A drum durability test was performed indoors under the conditions of an internal pressure of 190 kPa and a load of 646 kg. When there was no abnormality even after traveling 20,000 km, ○ was given, and when there was an abnormality, x was given, and the mileage when the abnormality occurred was shown.

[0064]

[Table 3]

[0065]

According to the present invention, it is possible to obtain a lighter tubeless tire having no inner liner, which has excellent adhesion between the case cord-covered rubber layer and another tire member mainly composed of diene rubber. .

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a case cord covering rubber layer according to a second embodiment of the present invention.

FIG. 2 is a schematic sectional view showing one embodiment of a case cord covering rubber layer according to a second embodiment of the present invention.

FIG. 3 is a schematic sectional view showing a layer structure in the vicinity of a case cord covering rubber layer of a conventional tubeless pneumatic tire.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Case cord covering rubber layer 2 Case cord covering inside rubber layer 3 Case cord covering outside rubber layer 4 Case cord 5 Bead part outside rubber layer 6 Bead 7 Inner liner 8 Side wall layer

Claims (2)

[Claims] 1. A tubeless tire having a case cord covering rubber layer having a case cord row therein, wherein the rubber composition for a case cord covering rubber layer comprises 50 to 90% by weight of a diene rubber and 50 to 10% by weight of a rubber. A tubeless pneumatic tire containing 100 parts by weight of a rubber component consisting of a bromide of isobutylene / p-methylstyrene copolymer and 1 to 10 parts by weight of a tackifier and having no plasticizer and without an inner liner. 2. A tubeless tire having a case cord covering rubber layer having a case cord row inside, wherein the case cord covering rubber layer is a tire from a case cord covering inner rubber layer and a case cord row of a tire inside portion to a tire inner part. An outer rubber layer of a case cord covering the outer portion, wherein the inner rubber layer of the case cord covers 50 to 9
A rubber component comprising 0% by weight of a diene rubber and 50 to 10% by weight of a bromide of isobutylene / p-methylstyrene copolymer, and 1 to 10 parts by weight of a tackifier; A tubeless pneumatic tire without an inner liner made of a rubber composition containing no.