JP2007217558A - Tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire excellent in performances on ice and excellent in dry performance and abrasion-resistant performance. <P>SOLUTION: This tire having a recycled rubber layer on a surface substantially contacting with road surfaces is characterized in that the recycled rubber layer comprises a foamed rubber containing at least a recycled rubber, and a rubber composition comprising 100 pts.mass of a new rubber including natural rubber and polybutadiene-based polymer and 1 to 30 pts.mass of the recycled rubber is used in the recycled rubber layer. The new rubber of the rubber composition used in the recycled rubber layer preferably comprises 20 to 70 mass% of the natural rubber and 30 to 80 mass% of the polybutadiene-based polymer. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a tire, particularly a tire excellent in performance on ice and excellent in performance on a dry road surface and wear resistance.

  Conventionally, it has been known that by using foamed rubber on the surface substantially in contact with the road surface of the tire, the surface substantially in contact with the road surface of the tire becomes rough, and the on-ice performance of the tire is improved. It is used as a tread for studless tires. However, since foamed rubber has low hardness, tires using foamed rubber on the surface substantially in contact with the road surface of the tire have reduced performance on dry road surfaces (hereinafter referred to as dry performance) and wear resistance. There is a problem to do.

  Japanese Patent Application Laid-Open No. 11-310009 (Patent Document 1) discloses a pneumatic tire in which a tread surface is covered with powder rubber having an average particle size of 50 to 500 μm. It has an advantage that the performance on ice in a wet ice burn near 0 ° C. does not change during the post-wear. However, the tire disclosed in Japanese Patent Application Laid-Open No. 11-310009 has the advantage that the performance on the ice in the wet ice burn does not change from the initial driving to the post-running wear, but the lower part of the powder rubber layer is the same as the tread of a normal studless tire Therefore, there is still room for improvement in dry performance and wear resistance.

JP 11-310009 A

  Accordingly, an object of the present invention is to solve the above-mentioned problems of the prior art and to provide a tire that is excellent in performance on ice, and also excellent in dry performance and wear resistance.

  As a result of intensive studies to achieve the above object, the present inventor has disposed a foamed rubber layer containing recycled rubber on a surface substantially in contact with the road surface of the tire, and a specific rubber composition in the foamed rubber layer. It has been found that the use of can improve the on-ice performance, dry performance and wear resistance performance of the tire, and the present invention has been completed.

  That is, the tire of the present invention includes a recycled rubber layer on a surface substantially in contact with the road surface, and the recycled rubber layer is made of foamed rubber containing at least recycled rubber. The recycled rubber layer includes natural rubber and polybutadiene-based heavy rubber. A rubber composition obtained by blending 1 to 30 parts by mass of recycled rubber with 100 parts by mass of new rubber including coalescence is used.

  In a preferred example of the tire of the present invention, the new rubber of the rubber composition used for the recycled rubber layer contains 20 to 70% by mass of natural rubber and 30 to 80% by mass of a polybutadiene-based polymer. In this case, the dry performance of the tire and the performance on ice can be sufficiently improved.

  In the tire of the present invention, the recycled rubber is preferably recycled rubber, butyl recycled rubber and powder rubber. Here, the recycled rubber includes (A) a coarse pulverization step in which a rubber chip is repeatedly coarsely pulverized by a diamond electrodeposition rotating drum and a diamond electrodeposition fixed blade one or more times to form fine powder, and (B) the coarse pulverization step. (C) a secondary pulverization step in which the recovered fine powder is further pulverized by a diamond electrodeposition rotating drum and a diamond electrodeposition fixed blade; The secondary pulverized and recovered step of collecting the dust pulverized in the next pulverizing step by sucking and collecting the secondary pulverized material that has not been recovered again into the secondary pulverizing step, and (E) the final pulverized product Particular preference is given to powder rubber produced through a product process which is taken out through a filter of a predetermined mesh. The powder rubber preferably has a particle size of 150 μm or less, and more preferably 80 μm or less.

  In the tire of the present invention, the recycled rubber layer preferably has a foaming rate of 3 to 50%.

  According to the present invention, a rubber composition obtained by blending 1 to 30 parts by weight of recycled rubber with 100 parts by weight of a new rubber containing natural rubber and a polybutadiene polymer on a surface substantially in contact with a road surface is used. It is possible to provide a tire having a recycled rubber layer made of foamed rubber formed and having excellent performance on ice, dry performance and wear resistance.

  The present invention is described in detail below. The tire of the present invention includes a recycled rubber layer on a surface substantially in contact with a road surface, the recycled rubber layer is made of foamed rubber containing at least recycled rubber, and the rubber composition used for the recycled rubber layer includes natural rubber and polybutadiene. A tire comprising 1 to 30 parts by mass of recycled rubber with 100 parts by mass of new rubber containing a polymer. In the tire of the present invention, since the recycled rubber layer disposed on the surface substantially in contact with the road surface is made of foamed rubber, the tire surface has high roughness and high performance on ice. Here, when the conventional foamed rubber is used on the surface substantially in contact with the road surface, as described above, the foamed rubber has low hardness, so that the dry performance and wear resistance of the tire are deteriorated. On the other hand, the recycled rubber layer of the tire of the present invention is made of foam rubber and contains recycled rubber, so that the hardness is improved while maintaining the roughness, and the dry performance and wear resistance of the tire are improved. It becomes possible to make it.

  The recycled rubber contained in the recycled rubber layer of the tire of the present invention is a rubber recovered from various rubber products, and examples of the recycled rubber include recycled rubber, butyl recycled rubber and powder rubber. Or may be used in combination of two or more. Recycled rubber is rubber obtained from a vulcanized rubber product, and butyl recycled rubber is rubber obtained from a rubber product made of butyl rubber.

  For the recycled rubber layer of the tire of the present invention, a rubber composition obtained by blending 1 to 30 parts by mass of recycled rubber with 100 parts by mass of new rubber containing natural rubber and a polybutadiene polymer is used. Here, the polybutadiene polymer is a polymer using butadiene as at least a part of the monomer, and specifically includes polybutadiene, styrene-butadiene copolymer, and the like.

  When the rubber composition used for the recycled rubber layer does not contain natural rubber as a new rubber, the dry performance of the tire is deteriorated, and the rubber composition used for the recycled rubber layer contains a polybutadiene polymer as the new rubber. Otherwise, the on-ice performance of the tire will deteriorate. In addition, if the amount of recycled rubber is less than 1 part by mass with respect to 100 parts by mass of the new rubber, the hardness of the recycled rubber layer is low, and the dry performance and wear resistance of the tire cannot be improved, while 30 masses. If it exceeds the part, the wear resistance of the tire is deteriorated.

  In the rubber composition used for the recycled rubber layer, the content of the natural rubber in the new rubber is preferably in the range of 20 to 70% by mass, and the content of the polybutadiene polymer in the new rubber is in the range of 30 to 80% by mass. Is preferred. If the content of the natural rubber in the new rubber is 20% by mass or more (the content of the polybutadiene polymer is 80% by mass or less), the dry performance of the tire can be sufficiently improved. If the natural rubber content is 70% by mass or less (polybutadiene polymer content is 30% by mass or more), the on-ice performance of the tire can be sufficiently improved.

  The recycled rubber used in the recycled rubber layer includes (A) a coarse pulverization step in which a rubber chip is repeatedly coarsely pulverized by a diamond electrodeposition rotating drum and a diamond electrodeposition fixed blade one or more times to form a fine powder, and (B) coarse pulverization. (C) a secondary pulverization step for further pulverizing the fine powder collected by the diamond electrodeposition rotating drum and the diamond electrodeposition fixed blade; A secondary pulverization and recovery step in which the finely pulverized product in the secondary pulverization step is sucked and collected, and the secondary pulverized material that is not recovered is sent again to the secondary pulverization step, and (E) the final pulverized product A powdered rubber produced through a product process in which the product is taken out through a filter with a predetermined mesh is preferable. The powdered rubber can be produced, for example, using a rubber chip pulverizing apparatus shown in FIGS.

  FIG. 1 is a process diagram showing a preferred embodiment of the production process of the powder rubber, in which A is a coarse pulverization process, B is a fine pulverization recovery process, C is a secondary pulverization process, Indicates the secondary pulverization recovery process, and E indicates the product process.

  First, in the coarse pulverization step A, the rubber chip G is introduced into the hopper 2 of the chip supplier 1, and the rubber chip G is introduced into the hopper 5 of the coarse pulverization mechanism 4 from the upper part of the chip supplier 1 through the supply pipe 3. Here, as the chip feeder 1, it is possible to use an elevator or the like that fixes a plurality of cups to the belt at an appropriate interval and rotates endlessly to convey a rose. In addition, the rubber chip G includes not only a bead extracted from a waste tire, but also a scrap rubber piece generated by pulsing a metal member from a waste rubber tube, unvulcanized scrap, etc. Can be used.

  As shown in detail in FIG. 2, the coarse pulverizing mechanism 4 includes a frame base 6 disposed close to the chip feeder 1, fixed on the frame base 6, and connected to a hopper 5 and a delivery pipe 7. A crusher outer box 8, a driving motor 10 that is fixed on the frame base 6 and rotates the diamond electrodeposition rotary drum 9 built in the crusher outer box 8, and provided on the side of the frame base 6. The screw conveyor 11 which connects the hopper 5 and the lower part of the crusher outer box 8 is provided. The screw conveyor 11 is formed of a tube body that houses a screw shaft having a drive motor on the upper end side, and moves the rubber chip G discharged from the discharge pipe 12 connected to the lower part of the crusher outer box 8 up and down again. Supply to hopper 5. Further, a calcium carbonate feeder 13 made of a screw conveyor is connected to the lower end side of the tubular body, and the calcium carbonate feeder 13 can supply an appropriate amount of calcium carbonate from the tank 14 into the screw conveyor 11. it can. Here, calcium carbonate has an action of reducing the bonding or adhesive strength between fine powders, and carbon black or the like can be substituted.

  As shown in the plan view of FIG. 3 and the side view of FIG. 4, the diamond electrodeposition rotating drum 9 built in the crusher outer box 8 is, for example, 80 mesh on the peripheral surface of the drum having a predetermined axial length and diameter. It has a structure in which diamond grains are electrodeposited and fixed, and a cooling pipe 16 is inserted through the shaft 15 of the diamond electrodeposition rotating drum 9 in the axial direction. An appropriate sprocket is pivotally attached to the shaft 15, and the diamond electrodeposited rotary drum 9 is pulverized by endlessly hanging a chain belt 17 between the sprocket and a sprocket pivotally attached to the reduction shaft of the drive motor 10. It can be rotated in the outboard box 8.

  Further, a diamond electrodeposition fixed blade 18 facing the diamond electrodeposition rotating drum 9 with a predetermined gap S is fixed in the outer box 8 of the grinder, and the diamond electrodeposition fixed blade 18 is The position can be adjusted by the mounting plate 19. The diamond electrodeposited fixed blade 18 is a block body having a substantially rectangular cross section having substantially the same axial length as the diamond electrodeposition rotary drum 9, and an arc along the circumferential surface of the diamond electrodeposition rotary drum 9 on the predetermined gap S side. For example, 80 mesh diamond grains are electrodeposited and fixed on the circular arc surface 20. Further, a cooling tube 21 is inserted through the diamond electrodeposited fixed blade 18 in the longitudinal direction. A fixing bolt 22 is screwed into a mounting plate 19 fixed in the crusher outer box 8 through a long hole 23 formed in the diamond electrodeposited fixed blade 18. As shown in FIGS. 2 and 4, in order to adjust the gap S, a stopper gilt 19 a applied to the diamond electrodeposited fixed blade 18 is fixed to the mounting plate 19 so that the screw can be adjusted.

  The rubber chip G dropped between the diamond electrodeposition rotary drum 9 and the diamond electrodeposition stationary blade 18 from the hopper 5 in the crusher outer box 8 is electrodeposited on the diamond electrodeposition rotary drum 9 and the diamond electrodeposition stationary blade 18. It is ground and crushed by fixed diamond grains, and is finely pulverized. At this time, the diamond electrodeposition rotary drum 9 and the diamond electrodeposition fixed blade 18 are cooled by circulating cooling media through the cooling pipes 16 and 21 of the diamond electrodeposition rotary drum 9 and the diamond electrodeposition fixed blade 18, respectively. Thus, the rubber chip G is prevented from melting and adhering to the surface thereof. The pulverized rubber chip G is sucked by an air volume adjusting blower 24 provided in the delivery pipe 7, and sent from the air volume adjusting blower 24 to a fine grinding and collecting step B by a transfer device 25 such as a screw or a conveyor. On the other hand, the coarsely pulverized material that has not been sucked and collected is transferred from the discharge pipe 12 at the bottom of the pulverizer outer box 8 into the hopper 5 by the screw conveyor 11, and again the diamond electrodeposition rotary drum 9 and the diamond electrodeposition fixed blade. It falls between 18 and crushed.

  Next, the roughly crushed rubber chip G is sent to the silo 26 by the transfer device 25 held at a required height in the fine pulverization and recovery step B. The silo 26 has a cyclone 27 in the upper part and a discharge port 28 in the lower part. A screw conveyor 29 having substantially the same structure as the screw conveyor 11 is connected to the dischargero 28. Is connected to the second hopper 5a of the fine grinding mechanism 4a used in the secondary grinding step C. Accordingly, the roughly crushed rubber chip G is sent from the silo 26 to the second hopper 5a via the screw conveyor 29 and supplied to the fine pulverizing mechanism 4a in the secondary pulverizing step C.

  The fine pulverization mechanism 4a in the secondary pulverization step C has substantially the same configuration as the coarse pulverization mechanism 4 described above, and is fixed on the second frame base 6a and the second frame base 6a, and the hopper 5a and the second pulverization mechanism 4a. A second crusher outer box 8a to which a delivery pipe 7a is connected, and a second diamond electrodeposition rotating drum 9a fixed on the second frame base 6a and built in the second crusher outer box 8a. Is provided with a second drive motor 10a and a second screw conveyor 11a provided on the side of the second frame base 6a. The second screw conveyor 11a is a tube body that houses a screw shaft having a drive motor on the upper end side, and lifts the rubber chip discharged from the discharge pipe 12a connected to the lower part of the second crusher outer box 8a. It is moved and supplied again to the second hobber 5a. In addition, a second calcium carbonate feeder 13a made of a screw conveyor is connected to the lower end portion of the tubular body, and the second calcium carbonate feeder 13a receives an appropriate amount of calcium carbonate from the second tank 14a. It can supply in the 2nd slewing conveyor 11a. Here, calcium carbonate has an action of reducing the bonding or adhesive strength between fine powders, and carbon black or the like can be substituted.

  Here, the configuration of the second diamond electrodeposition rotary drum 9a and the second diamond electrodeposition fixed blade 18a is the same as that of the diamond electrodeposition rotary drum 9 and the diamond electrodeposition fixed blade 18 described with reference to FIGS. The configuration is almost the same, but the difference is that the size of the electrodeposited Tyamond grains is 120 mesh. The diamond electrodeposition rotary drum 9 and the diamond electrodeposition fixed blade 18 in the coarse crushing mechanism 4 have a diamond particle size of 80 mesh, whereas the second diamond electrodeposition rotary drum 9a and the second in the fine crushing mechanism 4a By setting the size of the diamond grains in the diamond electrodeposited fixed blade 18a to 120 mesh, it is possible to achieve extremely high pulverization.

  In the second crusher outer box 8a, the rubber chips dropped from the hopper 5a between the diamond electrodeposition rotary drum 9a and the diamond electrodeposited fixed blade 18a are ground and crushed by the diamond grains to make fine powder. It becomes. At this time, the diamond electrodeposition rotary drum 9a and the diamond electrodeposition fixed blade 18a are circulated through the cooling tubes (not shown) of the diamond electrodeposition rotary drum 9a and the diamond electrodeposition fixed blade 18a. To prevent the rubber chip from melting and adhering to the surface. The pulverized rubber chips are sucked by an air volume adjusting blower 24a provided in the delivery pipe 7a, and sent from the air volume adjusting blower 24a to the secondary pulverizing and collecting step D by a transfer device 25a such as a screw or a conveyor. On the other hand, the secondary pulverized material that has not been sucked and collected is transferred from the discharge pipe 12a at the bottom of the pulverizer outer box 8a into the hopper 5a by the screw conveyor 11a, and again the diamond electrodeposition rotary drum 9a and the diamond electrodeposition. It falls between the fixed blades 18a and is crushed.

  Next, the secondary crushed rubber chip is sent to the second silo 26a by the transfer device 25a held at a required height in the secondary fine pulverization recovery step D. The silo 26a has a cyclone 27a in the upper part and a discharge port 28a in the lower part, and a screw conveyor 29a having substantially the same structure as the screw conveyor 29 is connected to the dischargero 28a. E is connected to the take-out container 30.

  Next, in the product process E, the fine powder discharged from the screw conveyor 29 a is received by the take-out container 30. A filter 31 of, for example, 100 to 300 mesh is provided in the opening on the side surface of the extraction container 30. In addition, a centrifuge 32 is accommodated in the take-out container 30, and the centrifuge 32 is rotated by an electric motor 34 that is also fixed to a frame base 33 to which the take-out container 30 is fixed. The take-out container 30 is surrounded by a cooling tank 35, and a third calcium carbonate feeder 13b and a third tank 14b are disposed above the take-out container 30, and calcium carbonate or carbon A separating material such as black can be supplied to the take-out container 30.

  In the product process E, the pulverized rubber chips discharged from the screw conveyor 29a are accommodated in the take-out container 30, and further, an appropriate amount of a separating material such as calcium carbonate or carbon black is mixed by the third calcium carbonate feeder 13b. By driving the centrifuge 32 in this state, the mixture is sent to the filter 31 side, further passes through the filter 31, and moves from the take-out container 30 into the product box 36. As a result, fine powder rubber that passes through a filter of 100 mesh or more is obtained as a product.

  The powder rubber obtained through the product process E preferably has a particle size of 150 μm or less, and more preferably 80 μm or less. Powder rubber having a particle size of 150 μm or less is unlikely to become a fracture nucleus in the recycled rubber layer, and it is difficult to reduce the wear resistance of the tire.

  The recycled rubber layer preferably has a foaming rate of 3 to 50%. When the foaming ratio of the recycled rubber layer is less than 5%, the on-ice performance of the tire cannot be sufficiently ensured. On the other hand, when it exceeds 50%, the dry performance and wear resistance of the tire may be deteriorated. The foaming rate of the recycled rubber layer can be appropriately changed depending on the type and amount of the foaming agent and foaming aid. Here, examples of the foaming agent include dinitrosopentamethylenetetramine (DNPT) and azodicarbonamide (ADCA), and examples of the foaming aid include urea.

  The rubber composition for the recycled rubber layer includes the above-mentioned new rubber, recycled rubber, foaming agent, foaming aid, filler, anti-aging agent, vulcanizing agent, vulcanization accelerator, zinc oxide, stearic acid. A compounding agent usually used in the rubber industry such as a softening agent can be appropriately selected and blended within a range not impairing the object of the present invention. As these compounding agents, commercially available products can be suitably used. The rubber composition for the recycled rubber layer is produced by blending a recycled rubber and various compounding agents appropriately selected as necessary with respect to the new rubber, and kneading, heating, extruding, etc. can do. The tire of the present invention can be produced according to a conventional method using such a rubber composition for a recycled rubber layer located on a surface substantially in contact with the road surface of the tire.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

  A rubber composition having the formulation shown in Table 1 was prepared according to a conventional method, and the rubber composition was placed on a surface substantially in contact with the road surface of the raw tire and vulcanized to produce a tire for passenger cars of size 185 / 70R13. did. The obtained tires were evaluated on ice performance, dry performance, and wear resistance performance by the following methods. The results are shown in Table 1.

(1) Performance on ice The above four test tires were mounted on a 1600cc passenger car and the braking performance on ice at an ice temperature of -1 ° C was confirmed. Specifically, run on a flat surface on ice, step on the brake at a speed of 20 km / h to lock the tire, measure the distance (braking distance) until it stops, and use the following formula:
Performance on ice = braking distance of tire of Comparative Example 1 / braking distance of test tire × 100 (index)
According to the index. The larger the index value, the shorter the braking distance and the better the braking performance on ice.

(2) Dry performance The above test tires are mounted on a 1600cc displacement passenger car, and the dry performance of the tire is expressed by the driver's feeling score in the actual vehicle test on the dry road surface. As an index. The larger the index value, the better the dry performance.

(3) Wear resistance performance The above four test tires were mounted on a 1600cc displacement passenger car, and the wear resistance performance was evaluated based on the amount of remaining grooves when traveling 10,000 kilometers in an actual vehicle test on a dry road surface. The larger the index value when the tire of Comparative Example 1 is 100, the better the wear resistance performance.

* 1 Ube Industries, UBEPOL 150L
* 2 N134, the nitrogen adsorption specific surface area ^{_{(N 2 SA) = 146m 2}} / g
* 3 Nippon Silica Co., Ltd., Nipsil AQ
* 4 Degussa, Si69
* 5 N-isopropyl-N'-phenyl-p-phenylenediamine
* 6 Dibenzothiazyl disulfide
* 7 N-cyclohexyl-2-benzothiazolesulfenamide
* 8 Dinitrosopentamethylenetetramine
* 9 Powder rubber produced through the series of steps shown in FIG. 1 (coarse pulverization step A, fine pulverization recovery step B, secondary pulverization recovery step C, secondary pulverization recovery step D and product step E), particle size = 75 μm
* 10 Whole tire reclaim, manufactured by Muraoka Rubber Co., Ltd.
* 11 Butyl tube reclaim, manufactured by Muraoka Rubber Co., Ltd.

  From the results of Examples and Comparative Example 1, rubber obtained by blending 1 to 30 parts by weight of recycled rubber with 100 parts by weight of new rubber containing natural rubber and polybutadiene polymer on the surface substantially in contact with the road surface It can be seen that the on-ice performance, dry performance and wear resistance performance of the tire can be improved by disposing a recycled rubber layer made of foamed rubber using the composition.

  Further, from the results of Example 1, Example 4, Example 5, Comparative Example 1 and Comparative Example 2, the amount of the recycled rubber in the rubber composition used for the recycled rubber layer was 30 with respect to 100 parts by mass of the new rubber. If it exceeds the mass part, the wear resistance performance of the tire deteriorates, and if it is less than 1 mass part, the improvement effect on the dry performance and wear resistance performance of the tire cannot be obtained, so the amount of recycled rubber is 1-30 parts by mass. You will find that you need to.

  Moreover, as a result of Comparative Example 3, when the rubber composition used for the recycled rubber layer does not contain a polybutadiene-based polymer, the performance on ice of the tire is deteriorated, and further, in Example 1, Example 2, and Example 3. As a result, it is found that the ratio of the polybutadiene polymer in the new rubber of the rubber composition used for the recycled rubber layer is preferably in the range of 30 to 80% by mass.

  Further, as a result of Comparative Example 4, when the rubber composition used for the recycled rubber layer does not contain natural rubber, the dry performance of the tire is lowered, and further, the results of Example 1, Example 2, and Example 3 are obtained. It can be seen that the ratio of natural rubber in the new rubber of the rubber composition used for the recycled rubber layer is preferably in the range of 20 to 70% by mass.

1 is a schematic configuration diagram of a rubber chip pulverizing apparatus suitable for producing powder rubber. It is a principal part enlarged view of a coarse grinding mechanism. It is a top view which shows a diamond electrodeposition rotating drum and a diamond electrodeposition fixed blade. It is a side view which shows a diamond electrodeposition rotating drum and a diamond electrodeposition fixed blade.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chip feeder 2 Hopper 3 Supply pipe 4 Coarse grinding mechanism 4a Fine grinding mechanism 5, 5a Hopper 6, 6a Frame base 7, 7a Delivery pipe 8, 8a Crusher outer box 9, 9a Diamond electrodeposition rotary drum 10, 10a drive Motor 11, 11a Screw conveyor 12, 12a Discharge pipe 13, 13a, 13b Calcium carbonate feeder 14, 14a, 14b Tank 15 Shaft 16 Cooling pipe 17, 17a Chain belt 18, 18a Diamond electrodeposited fixed blade 19 Mounting plate 20 Arc surface 21 Cooling tube 22 Fixing bolt 23 Long hole 24, 24a Air volume adjusting blower 25, 25a Transporter 26, 26a Silo 27, 27a Cyclone 28, 28a Discharge port 29, 29a Screw conveyor 30 Unloading container 31 Filter 32 Centrifugation Machine 33 Frame base 34 Electric motor 35 Retirement tank 36 product box

Claims (7)

A tire having a recycled rubber layer on a surface substantially in contact with a road surface,
The recycled rubber layer is made of foamed rubber containing at least recycled rubber,
A tire comprising a rubber composition obtained by blending 1 to 30 parts by mass of recycled rubber with 100 parts by mass of new rubber containing natural rubber and a polybutadiene-based polymer for the recycled rubber layer.   2. The tire according to claim 1, wherein the new rubber of the rubber composition used for the recycled rubber layer contains 20 to 70 mass% of natural rubber and 30 to 80 mass% of a polybutadiene polymer.   The tire according to claim 1, wherein the recycled rubber is at least one selected from the group consisting of recycled rubber, butyl recycled rubber and powder rubber.   The recycled rubber is (A) a coarse pulverization step in which a rubber chip is repeatedly coarsely pulverized by a diamond electrodeposition rotating drum and a diamond electrodeposition fixed blade one or more times to make a fine powder, and (B) pulverized in the coarse pulverization step. A fine pulverization and recovery step for sucking and collecting the object, (C) a secondary pulverization step for further pulverizing the recovered fine powder with a diamond electrodeposition rotating drum and a diamond electrodeposition fixed blade, and (D) the secondary pulverization step. A secondary pulverization and recovery step of collecting finely pulverized material by sucking and recovering the secondary pulverized material that has not been recovered again to the secondary pulverization step; The tire according to claim 1, wherein the tire is a powder rubber manufactured through a product process to be taken out.   The tire according to claim 4, wherein a particle diameter of the powder rubber is 150 μm or less.   The tire according to claim 5, wherein a particle diameter of the powder rubber is 80 μm or less.   The tire according to claim 1, wherein the recycled rubber layer has a foaming rate of 3 to 50%.

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