JP4962927B2 - Outsole and shoes equipped with this outsole - Google Patents

Description

  The present invention relates to shoes such as golf shoes, tennis shoes, soccer shoes, jogging shoes, trekking shoes, and town shoes, and an outsole used for these shoes.

  The shoe is composed of an outsole, an upper, an insole and the like. The outsole is typically formed from a rubber-based polymer composition. The outsole needs to grip the ground during exercise with landing and kicking. In particular, wet grip is important because it is slippery on wet ground.

It is also important that the outsole be lightweight. The weight of the outsole affects the weight of the shoe. Light shoes are suitable for exercise and comfortable. JP-A-2-149206 discloses an outsole containing bubbles. This outsole is lightweight because it contains bubbles, and has an instantaneous stop and slip resistance.
JP-A-2-149206

  However, the outsole described in JP-A-2-149206 has a problem that it has insufficient wear resistance because it contains bubbles.

  Further, in order to obtain an outsole composed of a rubber cross-linked product having excellent abrasion resistance, it is necessary to contain about 45 to 65 phr of a reinforcing agent such as silica and carbon black, but since this reinforcing agent has a large specific gravity, There is a problem that the outsole becomes heavy.

  An object of the present invention is to provide an outsole that is lightweight and has excellent grip and wear resistance.

An outsole according to the present invention has a grounding layer in contact with the ground, and a non-grounding layer formed above the grounding layer, and includes a laminated portion made of a polymer composition substantially free of bubbles. ,
The area ratio of the laminated portion to the entire bottom surface of the outsole is 70% or more,
The ground layer has a specific gravity of 1.00 or more and 1.23 or less,
The specific gravity of the non-ground layer is 0.90 or more and 1.13 or less,
The specific gravity of the ground layer is greater than the specific gravity of the non-ground layer,
The ground layer has a Shore A hardness of 55 or more and 95 or less.

  Preferably, each of the grounding layer and the non-grounding layer comprises acrylonitrile-butadiene rubber (NBR).

The shoe according to the present invention has a grounding layer in contact with the ground, and a non-grounding layer formed on the grounding layer, and includes a laminated portion made of a polymer composition substantially free of bubbles,
The area ratio of the laminated portion to the entire bottom surface of the outsole is 70% or more,
The ground layer has a specific gravity of 1.00 or more and 1.23 or less,
The specific gravity of the non-ground layer is 0.90 or more and 1.13 or less,
The specific gravity of the ground layer is greater than the specific gravity of the non-ground layer,
An outsole having a Shore A hardness of 55 to 95 in the ground contact layer is provided.

  In the outsole of the present invention, a ground layer having a Shore A hardness within a predetermined range and good wear resistance, and a non-ground layer that does not require wear resistance and has a specific gravity smaller than that of the ground layer, Since it is made of a two-layer structure comprising, it has excellent wear resistance and is lightweight. When the grounding layer and the non-grounding layer include NBR, the wet grip property is excellent and the adhesion between the grounding layer and the non-grounding layer is good.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a partially cutaway front view showing a shoe 1 according to an embodiment of the present invention, and FIG. 2 is a bottom view thereof. The shoe 1 includes an upper 3, a midsole 5, and an outsole 7. Although not shown, the shoe 1 also includes an insole. The outsole 7 includes a main body 9 and a large number of protrusions 11. The protrusion 11 protrudes downward from the main body 9. The protrusion 11 is formed integrally with the main body 9. Here, “integral molding” means a state in which the main body 9 and the protrusion 11 are bonded at the molecular level. This protrusion 11 provides anti-slip properties.

  FIG. 3 is a cross-sectional view taken along line III-III in FIG. The outsole 7 includes a laminated portion 15 made of a polymer composition that is substantially free of bubbles. The laminated portion 15 is made of so-called solid rubber. The laminated portion 15 made of solid rubber is excellent in wear resistance and stability, and has flexibility. Here, the air bubbles refer to those intentionally introduced by means such as foaming of a chemical foaming agent and blending of fine hollow spheres. That is, a gas composition that contains a small amount of bubbles (so-called voids) as a defect due to a gas that is unintentionally mixed or generated in a kneading step, a molding step, or the like of a polymer composition indicates It is included in "thing".

  The laminated portion 15 includes a grounding layer 17 that contacts the ground and a non-grounding layer 19 formed on the insole side of the grounding layer 17. As will be described later, the ground layer 17 has a large specific gravity α but is excellent in wear resistance. Since the non-ground layer 19 does not require wear resistance, the specific gravity β is set small. In the outsole 7 of the present embodiment, wear resistance and wet grip properties are imparted by the grounding layer 17 of the laminated portion 15, and weight reduction is achieved by the non-grounding layer 19.

  The outsole 7 may include a portion that is not a laminated structure in part. The area ratio of the laminated portion 15 to the entire bottom surface of the outsole 7 is preferably 70% or more. More preferably, the area ratio of the lamination | stacking part 15 is 75% or more, More preferably, it is 80% or more. The area ratio of the laminated portion 15 is the planar projected area of the laminated portion 15 occupying the planar projected area of the outsole 7.

  It is preferable that NBR is included as the base polymer of the ground layer 17. NBR has an effect of improving the wet grip performance of the outsole 7. NBR has a specific gravity of about 0.97 to 1.00, and has a large specific gravity as a polymer. Among NBR, those having an amount of bound acrylonitrile (AN) in NBR of 25% or more and 43% or less are preferable in terms of excellent wet grip properties. More preferably, it is NBR having a combined AN amount of 31% or more and 36% or less.

  As a base polymer for the grounding layer 17, together with NBR, VCR, isoprene rubber, styrene-butadiene rubber, butadiene rubber, butyl rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, ethylene-vinyl acetate copolymer, nitrile-isoprene rubber One or more of chloroprene rubber, urethane rubber and natural rubber can be used in combination. Here, the VCR means a rubber in which a high cis polybutadiene and a high crystalline syndiotactic polybutadiene are combined. Since the ground layer 17 is a portion that slides directly on the ground, it is necessary to have excellent wear resistance. Among the above, VCR, butadiene rubber, isoprene rubber, styrene-butadiene rubber and natural rubber are suitable as the base polymer used in combination from the viewpoint of maintaining good wear resistance. The ratio of NBR to the total rubber component is preferably 90% by mass or more.

  As the base polymer, a synthetic resin may be used together with rubber. When rubber and synthetic resin are used in combination, the proportion of rubber in the total base polymer is preferably 50% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more from the viewpoint of flexibility. 95 mass% or more is particularly preferable. From the viewpoint of flexibility, it is preferable that only rubber is used as the base polymer.

  In order to increase the wear resistance, means such as improvement of the crosslinking density, blending of a small diameter filler and the like may be used. Reinforcing fillers can be added to the polymer composition of the ground layer 17 to increase hardness. Generally, carbon black or silica as an inorganic filler is blended as a reinforcing filler. These carbon black and silica have a higher specific gravity than the polymer. From the viewpoint of obtaining a lightweight outsole 7, the amount of the reinforcing filler is preferably 70 parts by mass or less and more preferably 60 parts by mass or less with respect to 100 parts by mass of the base rubber.

  In order to provide appropriate hardness without increasing the specific gravity of the ground layer 17, it is preferable to use a resin filler in combination. By blending a resin filler into the ground layer 17, the effect of the reinforcing filler is supplemented. By using a resin filler, the amount of carbon black and silica is reduced. Since the specific gravity of the resin filler is low, the use of the resin filler contributes to the weight reduction of the outsole 7. It is particularly preferable that the resin filler has a specific gravity of 1.05 or less, further 1.00 or less, further 0.95 or less, and further 0.91 or less.

  Specific examples of preferred resin fillers include high styrene resins and syndiotactic 1,2-polybutadiene. The high styrene resin is a styrene-butadiene copolymer having a styrene resin content of 60% by mass or more. Syndiotactic 1,2-polybutadiene is a resin that contains 90% or more of 1,2-bonded vinyl components in the microstructure and the remaining components are cis-1,4 bonds or trans1,4 bonds.

  The blending amount of the resin filler is preferably 5 parts by mass or more and 35 parts by mass or less with respect to 100 parts by mass of the base rubber. If the amount is less than 5 parts by mass, the hardness is insufficient. The lower limit is more preferably 10 parts by mass. When the compounding amount of the resin filler exceeds 35 parts by mass, the wear resistance tends to be lowered. The upper limit is more preferably 30 parts by mass.

  The polymer composition for the ground layer 17 may be applied with sulfur crosslinking, peroxide crosslinking, or the like. In addition to the above polymer composition, an appropriate amount of a softening agent, a silylating agent, a silane coupling agent, an anti-aging agent, a vulcanization accelerator, a crosslinking aid, a colorant and the like are added as necessary.

  The polymer composition of the ground layer 17 has a specific gravity α of 1.00 to 1.23, a lower limit of preferably 1.03, more preferably 1.05, and an upper limit of preferably 1.22, more preferably. 1.20. When specific gravity (alpha) is less than 1.00, the compounding quantity of the said reinforcing filler will be small, and the outsole 7 is inferior to hardness and abrasion resistance. If the specific gravity α exceeds 1.23, the outsole 7 becomes heavy.

  The polymer composition of the ground layer 17 has a Shore A hardness of 55 to 95, the lower limit is preferably 65, more preferably 70, and the upper limit is preferably 90, more preferably 85. When the Shore A hardness is less than 55, the outsole 7 is inferior in stability. When the hardness is low because there are few reinforcing fillers, the wear resistance is poor. If the Shore A hardness exceeds 95, the outsole 7 is inferior in flexibility. The Shore A hardness is measured in accordance with JIS-K-6253 with a durometer hardness type A using a plate-shaped test piece having a thickness of 12 mm.

  The thickness of the ground layer 17 in the laminated portion 15 is preferably 1 mm or more in the main body 9 and the protrusion 11. More preferably, it is 1.5 mm or more. When the ground layer 17 is thickened, the non-ground layer 19 is thinned. If the non-grounding layer 19 is thin, the weight of the outsole 7 increases. From this viewpoint, the thickness of the ground layer 17 is preferably 7 mm or less, preferably 6 mm or less, and more preferably 4 mm or less. Further, in the laminated portion 15, the thickness of the ground layer 17 is not uniform and may be partially changed. For example, the thickness of the ground layer 17 may be increased in the protrusions 11 that are particularly required to have wear resistance and grip properties, and the other portions may be decreased.

  The base polymer of the non-grounding layer 19 preferably includes NBR. When the ground layer 17 includes NBR, the non-ground layer 19 necessarily includes NBR. Since NBR is inferior in adhesiveness to other rubber components (different in polarity), when the grounding layer 17 contains NBR, the adhesiveness between the grounding layer 17 and the non-grounding layer 19 is improved. The formation 19 also needs to contain NBR. Similar to the ground layer 17, among NBR, the amount of bonded AN in the NBR is preferably 25% or more and 43% or less from the viewpoint of excellent wet grip properties. More preferably, it is NBR having a combined AN amount of 31% or more and 36% or less.

  As a base polymer for the non-grounding layer 19, together with NBR, VCR, isoprene rubber, styrene-butadiene rubber, butadiene rubber, butyl rubber, ethylene-propylene rubber, ethylene-propylene-diene rubber, ethylene-vinyl acetate copolymer, nitrile-isoprene One or more of rubber, chloroprene rubber, urethane rubber and natural rubber can be used in combination. The ratio of NBR to the total rubber component is preferably 25% by mass or more.

  As the base polymer, a synthetic resin may be used together with rubber. When rubber and synthetic resin are used in combination, the proportion of rubber in the total base polymer is preferably 50% by mass or more, more preferably 80% by mass or more, and still more preferably 90% by mass or more from the viewpoint of flexibility. 95 mass% or more is particularly preferable. From the viewpoint of flexibility, it is preferable that only rubber is used as the base polymer.

  In the non-grounding layer 19, wear resistance is not necessary as much as required for the grounding layer 17, and thus high hardness is not necessarily required. When carbon black and silica that are reinforcing fillers are blended, the blending amount of the reinforcing filler is preferably 30 parts by mass or less with respect to 100 parts by mass of the base rubber from the viewpoint of weight reduction.

  Sulfur crosslinking is mainly applied to the polymer composition of the non-grounding layer 19. An appropriate amount of a softening agent, a silylating agent, a silane coupling agent, an antiaging agent, a vulcanization accelerator, a crosslinking aid, a coloring agent, and the like is added to the non-grounding layer 19 as necessary.

  In order to reduce the weight of the outsole 7, the specific gravity β of the polymer composition of the non-grounding layer 19 that does not require wear resistance is set to be smaller than that of the grounding layer 17. The specific gravity β is 0.90 to 1.13, the lower limit is preferably 0.92, more preferably 0.93, and the upper limit is preferably 1.12 and more preferably 1.10. It is difficult in design to make the specific gravity β less than 0.90. Moreover, if specific gravity (beta) exceeds 1.13, the outsole 7 will become heavy.

  The ratio α / β of the specific gravity α of the ground layer 17 and the specific gravity β of the non-ground layer 19 is 1.03 to 1.20, the lower limit is preferably 1.05, more preferably 1.08, and the upper limit is Preferably it is 1.15, More preferably, it is 1.12. When α / β is small, the specific gravity α of the grounding layer 17 decreases and wear resistance decreases, or the specific gravity β of the non-grounding layer 19 increases and the outsole 7 becomes heavy, improving wear resistance and reducing weight. The object of the present invention cannot be sufficiently achieved. Further, when α / β is large, the specific gravity α of the grounding layer 17 becomes large, the outsole 7 becomes heavy, the strength of the non-grounding layer 19 becomes insufficient, and the strength necessary for the outsole 7 is difficult to be maintained.

  The polymer composition of the non-ground layer 19 has a Shore A hardness of 55 to 95, the lower limit is preferably 65, more preferably 70, and the upper limit is preferably 90, more preferably 85. When the Shore A hardness is less than 55, the outsole 7 is inferior in stability. If the Shore A hardness exceeds 95, the outsole 7 is inferior in flexibility.

  If the thickness of the non-grounding layer 19 is too thin, the grounding layer 17 becomes thick and the outsole 7 becomes heavy. On the other hand, if the thickness of the non-grounding layer 19 is too thick, the thickness of the grounding layer 17 is reduced and the wear resistance is reduced. From this viewpoint, the thickness of the non-grounding layer 19 is preferably 10% or more and 65% or less of the thickness of the laminated portion 15. Further, in the laminated portion 15, the thickness of the non-grounding layer 19 is not uniform and may be partially changed.

  In the manufacture of the outsole 7, first, a mold having an upper mold and a lower mold is prepared. A concave portion corresponding to the protrusion 11 is provided on the inner surface of the lower mold. The lower mold is filled with the polymer composition for the ground layer 17. This polymer composition is pressed by a plate having a shape that conforms to the inner shape of the lower mold, and the ground layer 17 is preformed. The preformed ground layer 17 is filled with the polymer composition for the non-ground layer 19. The upper mold is lowered and combined with the lower mold filled with these polymer compositions, and is pressed and heated. By this heating, the polymers of the grounding layer 17 and the non-grounding layer 19 cause a crosslinking reaction, whereby the laminated portion 15 is formed and the outsole 7 is obtained.

  FIG. 4 is a sectional view showing an outsole 23 according to another embodiment of the present invention, and FIG. 5 is a back view of the outsole 23. A large number of protrusions 27 are provided on the main body 25 of the outsole 23. The outsole 23 includes a laminated portion 29 and a non-laminated portion 35 made of a polymer composition that does not substantially contain bubbles. In FIG. 5, the laminated portion 29 is indicated by a hatched portion. In the outsole 23, a non-stacked portion 35 is continuously provided behind the buttocks side of the stacked portion 29. The laminated portion 29 is composed of a ground layer 31 and a non-ground layer 33, which are composed of the same composition as the ground layer 17 and the non-ground layer 19, respectively. Therefore, the laminated portion 29 has wet grip properties and wear resistance, and is lightened. The non-laminated portion 35 has the same composition as the ground layer 17. Since the heel portion wears violently, it is the same component as the ground layer 17 having good wear resistance, and is configured as a non-laminated portion 35 having a single layer structure. In order for the laminated portion 29 to exhibit the above-described effect, the area ratio of the laminated portion 29 occupying the bottom surface of the outsole 23 needs to be 70% or more. More preferably, the area ratio of the laminated portion 29 is 75% or more, and more preferably 80% or more. From the viewpoint of preventing hip wear, the upper limit of the area ratio of the laminated portion 29 is preferably 95%.

  Hereinafter, the effects of the present invention will be clarified by examples. However, the present invention should not be construed in a limited manner based on the description of the examples.

[Preparation of polymer composition]
The blends shown in Table 1 below were kneaded with a closed kneader and an open roll to obtain polymer compositions having blend numbers of A1 to A10 for the ground layer. Further, the blends shown in Table 2 were kneaded with a closed kneader and an open roll to obtain polymer compositions having blend numbers of B1 to B3 for non-ground layers. In Tables 1 and 2, the blending amount is represented by a mass ratio. Tables 1 and 2 also show the specific gravity, Shore A hardness, and Akron wear amount of each polymer composition. Shore A hardness is measured by the measurement method described above. The amount of Akron wear is measured according to the “A-2 method” of the Akron wear test defined in JIS-K-6264. In this wear amount measurement, the thickness of the wear wheel is 25 mm, the inclination angle between the test piece and the wear wheel is 15 °, the load applied to the wear wheel is 44.1 N, and the rotation speed of the test piece is 250 rpm. It is said.

Details of the polymers and additives shown in Tables 1 and 2 are as follows.
* 1 NBR (Nansei's product name “NANCAR 1052”, AN amount: 33.0%)
* 2 NBR (Nippon Zeon's trade name “Nipol DN315”, AN amount: 26.0%)
* 3 VCR (Ube Industries' product name “UBEPOL VCR617”, SPB amount: 17.0%)
* 4 IR (trade name “Nipol IR-2200” of Zeon Corporation)
* 5 Syndiotactic polybutadiene resin (“RB830” from Nippon Synthetic Rubber)
* 6 High styrene resin (Ameripol Synpol's product name “AMERIPOL1904”)
* 7 Carbon Black (Mitsubishi Chemical's trade name “Dia Black I”)
* 8 Silica (Degussa's “Ultra Gil VN3”)
* 9 Polyethylene glycol (Nippon Yushi Co., Ltd. trade name “PEG4000”)
* 10 Silane coupling agent: bis (3-triethoxysilylpropyl) tetrasulfene (Degussa “Si69”)
* 11 Dioctyl phthalate (trade name “DOP” by Sanken Chemical Co., Ltd.)
* 12 Anti-aging agent (trade name “Sunnock N” from Ouchi Shinsei Chemical Co., Ltd.)
* 13 Anti-aging agent: 2,6-di-tert-butyl-methylphenol (trade name “NOCRACK 200” from Ouchi Shinsei Chemical Co., Ltd.)
* 14 Micro Balloon (trade name “Expansel DU80” by Nihon Philite)
* 15 Vulcanization accelerator: dibenzothiazyl disulfide (Ouchi Shinsei Chemical Co., Ltd. trade name “Noxeller DM”)
* 16 Vulcanization accelerator: Tetraethylthiuram disulfide (trade name “Noxeller TET” by Ouchi Shinsei Chemical Co., Ltd.)
* 17 Vulcanization accelerator: Di-o-tolylguanidine (trade name “Noxeller DT” of Ouchi Shinsei Chemical Co., Ltd.)
* 18 Vulcanization accelerator: N-tert-butyl-2-benzothiazolylsulfenamide (trade name “Noxeller NS” from Ouchi Shinsei Chemical Co., Ltd.)

[Example 1]
The lower mold of the above-described mold was filled with the polymer composition of A1 in Table 1, and this polymer composition was pressed with a plate having a shape along the inner surface shape of the lower mold to obtain a preformed ground layer. . The preformed ground layer was filled with the polymer composition of B1 in Table 2. The upper mold was aligned with the lower mold filled with these polymer compositions, and pressed and heated. By this heating, the polymer of the grounding layer and the non-grounding layer caused a crosslinking reaction to form a laminated portion and to obtain an outsole.

[Examples 2 to 5]
Each outsole was obtained in the same manner as in Example 1 except that the composition of the grounding layer and the non-grounding layer was as shown in Table 3. In addition, the part which is not a lamination | stacking part was formed with the polymer composition for grounding layers.

[Comparative Example 1]
An outsole was obtained by molding in the same manner as in Example 1 except that the area ratio of the laminated portion in the outsole was 60%.

[Comparative Examples 2 to 6]
Each outsole was obtained in the same manner as in Example 1 except that the composition of the grounding layer and the non-grounding layer was as shown in Table 4 below.

[Comparative Example 7]
An outsole was obtained by molding using only the polymer composition A10 for the ground layer without providing a laminated portion.

[Evaluation]
[Abrasion resistance]
An outsole was placed on the ground made of asphalt concrete, a weight of 10 kg was placed on the outsole, and the outsole was dragged. Thus, the volume of the outsole at the stage where the distance of 50 cm was reciprocated 100 times was measured, and the difference from the volume before dragging was calculated. The results are shown in Tables 3 and 4 above.

[Evaluation of wet grip]
A golf shoe was obtained by attaching a midsole and an upper to the outsole. This golf shoe was worn by a golfer to walk and hit a golf ball on wet grass and on the road surface. Then, with respect to the slipping of the shoes, the non-slipable one was rated as “5”, and the slippery one as “1” was rated in five stages. Table 3 and Table 4 show the average scores of 10 golfers.

[Stability, flexibility and lightness]
Similarly to the evaluation of the wet grip property, shoes were worn by 10 testers and rated for ease of walking and practicality during exercise. The average values are shown in Tables 3 and 4 by evaluating stability, flexibility and lightness as evaluation items. The larger the numerical value, the higher the stability associated with the exercise, the better the flexibility along the foot, and the lighter the shoe.

  As shown in Table 3 and Table 4, the shoe to which the outsole of Comparative Example 1 is attached is heavy because the area ratio of the laminated portion is small. The shoe of Comparative Example 2 has poor stability because the Shore A hardness of the ground contact layer is small. In the shoe of Comparative Example 3, the Shore A hardness of the ground contact layer is large and the flexibility is poor. In Comparative Example 4, the wear resistance of the grounding layer is poor, and the wear resistance of the entire outsole is poor. Moreover, the wet grip property of shoes is also bad. In the shoe of Comparative Example 5, the specific gravity of the ground layer and the non-ground layer is large and heavy. In the shoe of Comparative Example 6, the non-ground layer has a large specific gravity and is heavy. The shoe of Comparative Example 7 has a single layer structure in which the outsole is composed of a component of the ground layer, and has a large specific gravity and is heavy. The outsole of the example and the shoe to which the outsole is attached have a higher evaluation than the outsole of the comparative example and the shoe to which the outsole is attached. From this evaluation result, the superiority of the present invention is clear. In Example 5, since NBR is not blended in the ground layer and the non-ground layer, the wet grip property is poor.

  The present invention can be applied to golf shoes, tennis shoes, walking shoes, jogging shoes, trekking shoes, women's shoes, men's shoes, and the like.

FIG. 1 is a partially cutaway front view showing a shoe according to an embodiment of the present invention. 2 is a bottom view of the shoe of FIG. FIG. 3 is a cross-sectional view taken along line III-III in FIG. FIG. 4 is a cross-sectional view illustrating an outsole according to another embodiment of the present invention. FIG. 5 is a bottom view showing the outsole of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Shoes 3 ... Upper 5 ... Mid sole 7, 23 ... Outsole 9, 25 ... Main body 11, 27 ... Protrusion 15, 29 ... Laminate part 17, 31, ..Grounding layer 19, 33 ... Non-grounding layer 35 ... Non-laminated part

Claims (2)

It has a midsole and an outsole,
The outsole has a grounding layer in contact with the ground, and a non-grounding layer formed on the grounding layer, and includes a laminated portion made of a polymer composition substantially free of bubbles,
The area ratio of the laminated portion to the entire bottom surface of the outsole is 70% or more,
The ground layer has a specific gravity of 1.00 or more and 1.23 or less,
The specific gravity of the non-ground layer is 0.90 or more and 1.13 or less,
The specific gravity of the ground layer is greater than the specific gravity of the non-ground layer,
The ground layer has a Shore A hardness of 55 to 95,
The polymer composition of the ground layer includes a base polymer and a reinforcing filler,
Amount of the reinforcing filler, Ri 70 parts by der less than 45 parts by mass with respect to the base polymer 100 parts by weight,
The substrate polymer, acrylonitrile - Ru butadiene rubber der, shoes. Upper Kihi ground layer, acrylonitrile - Shoe according to claim 1 comprising a butadiene rubber.

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