JP2007077270A - Cold resistant rubber composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cold resistant rubber composition excellent in oil resistance and cold resistance, and to provide a hose, tank seal and oil resistant belt using the composition. <P>SOLUTION: The cold resistant rubber composition comprises an acrylonitrile-butadiene rubber (NBR), and a coagulum of quartz and kaolinite. The cold resistant rubber composition preferably contains 1-100 pts by mass of the coagulum based on 100 pts by mass of the NBR. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a cold resistant rubber composition. More specifically, the present invention relates to a rubber composition that uses acrylonitrile-butadiene rubber (NBR), such as a marine hose, a high-pressure hose, a tank seal, and an oil-resistant belt, and that can be used for applications that require cold resistance.

Marine hoses, high-pressure hoses, tank seals and oil-resistant belts are generally used for materials such as the inner rubber layer (rubber tube layer) and outer rubber layer (cover rubber layer) from the viewpoint of oil resistance (swelling resistance). NBR having a high to extremely high amount of bound acrylonitrile is used.
However, as the amount of bonded acrylonitrile in NBR increases, the embrittlement temperature of the rubber becomes higher (about −15 to −20 ° C.), so that the inner surface is kept at a very low temperature (about −35 to −40 ° C.). Since there is concern about fluid leakage due to the occurrence of cracks in the rubber layer, there has been a problem of cold resistance such that it becomes difficult to use in extremely cold regions.

Therefore, in order to solve the above problem, Patent Document 1 proposes a hose in which an inner rubber layer is formed of an NBR-based rubber composition to which a cold-resistant plasticizer is added while maintaining the amount of NBR-bound acrylonitrile to a certain level. Has been.
However, the hose described in Patent Document 1 has a problem in that cold resistance is further deteriorated as a result of the cold resistant plasticizer being extracted by the fluid during use and the fluid penetrating into the inner rubber layer.

Japanese Patent Laid-Open No. 11-304058

  Then, this invention makes it a subject to provide the rubber composition for cold resistance which is excellent in both oil resistance and cold resistance, and a hose, a tank seal, and an oil-resistant belt using the said composition.

  As a result of intensive studies to solve the above problems, the present inventor has found that a specific rubber composition in which an aggregate of quartz and kaolinite is added to NBR is excellent in both oil resistance and cold resistance. The present invention has been completed.

That is, the present invention provides a cold-resistant rubber composition as described in (1) to (8) below, and a hose, a tank seal and an oil-resistant belt using the composition.
(1) A cold resistant rubber composition containing acrylonitrile-butadiene rubber (NBR) and an aggregate of quartz and kaolinite.
(2) The cold resistant rubber composition according to (1), wherein the content of the aggregate is 1 to 100 parts by mass with respect to 100 parts by mass of the NBR.
(3) The cold-resistant rubber composition according to the above (1) or (2), wherein the amount of bound acrylonitrile of the NBR is 15 to 55% by mass.
(4) The cold resistant rubber composition according to any one of (1) to (3), wherein the NBR content is 25 to 60% by mass.
(5) The cold resistant rubber composition according to any one of (1) to (4), further containing 10 to 150 parts by mass of carbon black with respect to 100 parts by mass of the NBR.
(6) A hose comprising at least an inner rubber layer and a reinforcing layer, and the inner rubber layer is made of the cold resistant rubber composition according to any one of (1) to (5).
(7) A tank seal comprising at least an outer rubber layer and a reinforcing layer, and the outer rubber layer comprising the cold-resistant rubber composition according to any one of (1) to (5).
(8) An oil-resistant belt comprising at least a cover rubber layer and a reinforcing layer, and the cover rubber layer comprising the cold-resistant rubber composition according to any one of (1) to (5).

  As will be described below, according to the present invention, it is possible to provide a cold-resistant rubber composition that is excellent in both oil resistance and cold resistance, and even in extremely cold regions, a hose (for example, a marine hose) and a tank Since it can be used for materials such as seals and oil-resistant belts, it is very useful.

The present invention is described in detail below.
The cold resistant rubber composition of the present invention (hereinafter also simply referred to as “the rubber composition of the present invention”) is a cold resistant rubber containing acrylonitrile-butadiene rubber (NBR) and an aggregate of quartz and kaolinite. It is a composition.
Next, NBR and the aggregate of quartz and kaolinite will be described in detail.

<NBR>
NBR used in the rubber composition of the present invention is not particularly limited, but from the viewpoint of oil resistance, the amount of bound acrylonitrile is preferably 15 to 55% by mass, more preferably 25 to 45% by mass, and 28 to More preferably, it is 40 mass%.
Further, the NBR content in the rubber composition of the present invention (mass ratio with respect to the mass of the entire rubber composition) is preferably 25 to 60% by mass, and more preferably 35 to 45% by mass. It is preferable for the content to be in this range since the resulting rubber composition of the present invention has better oil resistance.

  In the present invention, a commercially available product can be used as such NBR. Specific examples thereof include perbunan 1845 (bound acrylonitrile amount: 18%, manufactured by Bayer), Nipol 1043 (bound acrylonitrile amount: 29%, manufactured by Nippon Zeon). ), Nipol 1042 (33% bound acrylonitrile, manufactured by Nippon Zeon), Nipol DN3335 (33% bound acrylonitrile, manufactured by Nippon Zeon), Nipol 1041 (41% bound acrylonitrile, manufactured by Nippon Zeon), Nipol DN005 ( Bonded acrylonitrile amount 44%, manufactured by Nippon Zeon Co., Ltd.) and the like may be used alone or in combination of two or more.

<Aggregates>
The aggregate used in the rubber composition of the present invention is not particularly limited as long as it is an aggregate of quartz and kaolinite.
In the present invention, commercially available products can be used as such aggregates. Specific examples thereof include siritin (Siritin Z86, Siritin V85, Siritin N82, Siritin 85, Siritin N87, AKTISIL PF216 (all of which are Hoffman Minerals). (Product made)) etc. are mentioned suitably. In addition, what has the same structure manufactured artificially can also be used.

  By using such an aggregate, the obtained rubber composition of the present invention has not only oil resistance but also cold resistance. In consideration of the fact that in the embodiment containing only quartz (silica), quartz in the rubber composition obtained is aggregated and the micro-Brownian motion of rubber molecules at a low temperature is suppressed. The plate-like kaolinite in the inside prevents the suppression of micro-Brownian motion of rubber molecules due to quartz, so the rubber composition becomes more flexible even at extremely low temperatures, and the low temperature embrittlement temperature is considered to have decreased. It is done.

  In the present invention, the mass ratio of quartz and kaolinite constituting the aggregate (quartz: kaolinite) is not particularly limited, but from the viewpoint of better flexibility of the rubber composition even at extremely low temperatures, It is preferably 12: 1 to 1: 1, more preferably 9: 1 to 2: 1.

  In the present invention, the aggregate may contain iron oxide, phosphorus component, sulfur component and the like in addition to quartz and kaolinite. These aggregates may be used alone or in combination of two or more.

  Furthermore, in this invention, it is preferable that content of the said aggregate is 1-100 mass parts with respect to 100 mass parts of said NBR, and it is more preferable that it is 10-40 mass parts. When the content is in this range, the resulting rubber composition of the present invention has better cold resistance and good processability, which is preferable. “Good processability” means that the rubber composition of the present invention is easily prepared, or that the rubber composition is easily processed when used for materials such as hoses, tank seals, and oil-resistant belts. Means.

In one preferred embodiment, the rubber composition of the present invention contains carbon black.
The carbon black used in the present invention is not particularly limited. Specifically, for example, SAF (Super Abrasion Furnace), ISAF (Intermediate Super Abrasion Furnace), HAF (High Ablation Furnace), and FEF (Fast Ex Furting P). (General Purpose Furnace), SRF (Semi-Reinforcing Furnace), FT (Fine Thermal), MT (Medium Thermal), and the like can be used.
More specifically, as the SAF, Seast 9 (manufactured by Tokai Carbon Co., Ltd.), ISAF as Showa Black N220 (manufactured by Showa Cabot Corporation), HAF as Seast 3 (manufactured by Tokai Carbon Co., Ltd.), and FEF as HTC # 100 (Chubu Carbon Co., Ltd.) etc. are illustrated. As GPF, Asahi # 55 (Asahi Carbon Co., Ltd.), Seest 5 (Tokai Carbon Co., Ltd.), SRF Asahi # 50 (Asahi Carbon Co., Ltd.), Mitsubishi # 5 (Mitsubishi Chemical Co., Ltd.), FT Asahi Thermal (manufactured by Asahi Carbon Co., Ltd.), HTC # 20 (manufactured by Chubu Carbon Co., Ltd.), Asahi # 15 (manufactured by Asahi Carbon Co., Ltd.) and the like are exemplified.
Among such carbon blacks, nitrogen adsorption specific surface area of 15~150m ² / g, it is preferably preferably is carbon black of 20 to 50 m ² / g.
Nitrogen adsorption specific surface area is a value obtained by measuring the surface area of carbon black that can be used for adsorption with rubber molecules by nitrogen adsorption. If it is within the above range, product performance (especially hardness) ) Is not impaired, and the polymer fraction is small, so that not only oil resistance but also cold resistance is improved, which is preferable.

  The content of carbon black that can be optionally used in the present invention is preferably 10 to 150 parts by mass, more preferably 50 to 120 parts by mass, and more preferably 60 to 100 parts by mass with respect to 100 parts by mass of the NBR. More preferably, it is part. When the content is within this range, the hardness becomes favorable, and not only the oil resistance but also the cold resistance becomes better, which is preferable.

The rubber composition of the present invention may contain a filler other than carbon black as needed, as long as the object of the present invention is not impaired. Specifically as fillers other than carbon black, for example, soft clay such as T-clay, kaolin clay, wax stone clay, sericite clay, calcined clay; diatomaceous earth; heavy calcium carbonate, magnesium carbonate; Examples include fumed silica, calcined silica, precipitated silica, pulverized silica, and fused silica.
Moreover, as for content of such a filler, 10 mass parts or more are preferable with respect to 100 mass parts of said NBR, More preferably, it is 15-30 mass parts. If the content is within this range, oil resistance and cold resistance become better, which is preferable.

  In addition, the rubber composition of the present invention can be added to other additives, for example, a vulcanizing agent such as sulfur and zinc oxide; an organic sulfur-containing compound such as TMTD; Organic peroxides such as mill peroxide; sulfenamides such as N-cyclohexyl-2-benzothiazolesulfenamide (CBS), thiazoles such as mercaptobenzothiazole, thiuram such as tetramethylthiuram monosulfide, stearic acid Vulcanization accelerators such as: TMDQ and other ketones and amine condensates, DNPD and other amines, styrenated phenols and other monophenols, etc .; DBP, DOP and other phthalic acid derivatives, DBS and other sebacic acids Plasticizers such as monoesters such as derivatives; Softeners such as paraffinic oil (process oil, etc.); Vulcanization Agent; may contain a heat-resistant agent; flame retardants; weathering agents.

  The method for producing the rubber composition of the present invention is not particularly limited, and an unvulcanized rubber composition containing the NBR, the aggregates, and carbon black, fillers, and various additives that can be optionally contained is appropriately selected. It can be molded and prepared by kneading using a known method and apparatus.

The hose of the present invention is a hose comprising at least an inner rubber layer and a reinforcing layer, and the inner rubber layer is made of the rubber composition of the present invention described above.
Examples of such hoses include marine hoses and high-pressure hoses, specifically, a hose body and a mounting flange. The hose body includes an inner rubber layer, a reinforcing layer, an intermediate rubber layer, and a buoyancy material layer. A marine hose provided with a cover rubber layer in this order is preferably exemplified.

An example of a preferred embodiment of the marine hose will be described with reference to FIGS. FIG. 1 is an external view showing an example of a preferred embodiment of the hose of the present invention, and FIG. 2 is a cross-sectional view of an essential part in the direction of arrows AA shown in FIG.
As shown in FIGS. 1 and 2, the hose 10 includes a hose body 11 and a mounting flange 12. The mounting flange 12 is provided at both ends of the hose body 11 in order to connect the plurality of hoses 10 to each other. It has been.

  The hose body 11 is provided with an inner rubber layer 112 as the innermost layer, and a reinforcing layer 113 that holds liquid such as oil passing through the hose 10 on the outer side (outer peripheral side).

Further, an intermediate rubber layer 114 having a body wire 114a embedded therein is provided outside the reinforcing layer 113, and a cover rubber layer 115 for covering the hose body 11 is applied to form an integral structure.
Further, a buoyancy material layer 116 is filled inside the cover rubber layer 115 so that it easily floats on the sea or the like.

On the other hand, the attachment flange 12 is integrally provided with ring portions 122a, 122b, 122c for attaching the hose body 11 along the circumferential direction of the outer peripheral surface of the cylindrical portion 121.
The end portion of the hose body 11 is fixed between the ring portions 122a to 122c of the mounting flange 12 by fastening wires 113b and 114b, and the end portions of the respective layers forming the hose body 11 are adhesively bonded. The fastening wires 113b and 114b are provided at the ends of the reinforcing layer 113 and the intermediate rubber layer 114.

  Next, the inner rubber layer, the reinforcing layer, the intermediate rubber layer, the buoyancy material layer, and the cover rubber layer will be described in detail.

<Inner rubber layer>
The inner rubber layer is formed of the rubber composition of the present invention, and may be formed of a single layer or a plurality of layers.

  In the present invention, the thickness of the inner rubber layer is not particularly limited because it can be appropriately changed depending on the application (for example, the type of fluid to be transported) in which the marine hose is used, but it contains a large amount of aroma components such as crude oil. When transporting a fluid, the thickness is preferably about 4 to 12 mm.

<Reinforcing layer>
As the reinforcing layer, a conventionally known reinforcing layer used for marine hoses can be used. The reinforcing layer may be formed of a single layer or a plurality of layers. FIG. 3 is a diagram illustrating the configuration of the reinforcing layer.
As shown in FIGS. 2 and 3, each of the plurality of reinforcing layers 113 has a plurality of cords 113 a arranged in an inclined manner with respect to the longitudinal direction of the hose body 11. The reinforcing layer 113 is laminated so that cords 113a having different orientation angles (θ1) with respect to the longitudinal direction of the hose cross each other, and the number of laminated layers is equal.

  In addition, the orientation angle θ1 of the cord 113a is preferably 30 degrees <θ1 <60 degrees, and more preferably 35 degrees <θ1 ≦ 55 degrees. If the orientation angle θ1 of the cord 113a is within this range, the flexibility and flexibility of the hose body 11 are excellent.

  Specific examples of such a reinforcing layer include those formed by twisting cords made of nylon fiber, polyester fiber, rayon fiber, aromatic polyamide fiber, steel wire, and the like.

  In the present invention, the thickness of the reinforcing layer is not particularly limited because it can be appropriately changed depending on the application (for example, the type of fluid to be transported) in which the marine hose is used, but a fluid containing a large amount of aroma components such as crude oil. Is preferably about 5 to 25 mm.

<Intermediate rubber layer>
The intermediate rubber layer may be a conventionally known intermediate rubber used for marine hoses, and may be formed of one layer alone or a plurality of layers.
Specific examples of rubber materials for forming such an intermediate rubber layer include natural rubber (NR), butadiene rubber (BR), butyl rubber (IIR), chlorinated butyl rubber (Cl-IIR), and brominated butyl rubber. (Br-IIR), ethylene-propylene rubber (EPM), ethylene-propylene-diene rubber (EPDM), styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), chlorosulfonated polyethylene rubber (CSM) and the like. These may be used alone or in combination of two or more.
Of these, the use of natural rubber (NR) is preferable because the strength of the marine hose obtained can be maintained.

In the present invention, the intermediate rubber layer may be formed of rubber alone, but may be formed of a rubber composition containing various additives from the viewpoint of ensuring the performance as a marine hose. .
Examples of the additive that may be contained as necessary include various additives exemplified above as the rubber composition for forming the inner rubber layer.

  In the present invention, the thickness of the intermediate rubber layer is not particularly limited because it can be appropriately changed depending on the use in which the marine hose is used (for example, the type of fluid to be transported). When transporting a fluid containing a large amount, it is preferably about 5 to 15 mm.

<Buoyancy material layer>
The buoyancy material layer may be a conventionally known buoyancy material layer used for marine hoses, and may be formed of one layer alone or a plurality of layers.
Specific examples of a material for forming such a buoyancy material layer include a foaming floater.

  In the present invention, the thickness of the buoyancy material layer is not particularly limited because it can be appropriately changed depending on the application (for example, the type of fluid to be transported) in which the marine hose is used. When transporting a fluid, the thickness is preferably about 100 to 200 mm.

<Cover rubber layer>
As the cover rubber layer, a conventionally known cover rubber layer used for marine hoses can be used. The cover rubber layer may be formed of a single layer or a plurality of layers.
Specific examples of the rubber material forming such a cover rubber layer include natural rubber (NR), butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), and butyl rubber (IIR). ), Chlorinated butyl rubber (Cl-IIR), brominated butyl rubber (Br-IIR), ethylene-propylene-diene rubber (EPDM), chlorosulfonated polyethylene rubber (CSM) and the like. Two or more kinds may be mixed and used.
Among these, it is preferable to use natural rubber (NR) for the reason that the obtained marine hose is excellent in wear resistance and strength retention.

In the present invention, the cover rubber layer may be formed of rubber alone, but may be formed of a rubber composition containing various additives from the viewpoint of ensuring the performance as a marine hose. .
Examples of the additive that may be contained as necessary include various additives exemplified above as the rubber composition for forming the inner rubber layer.

  Further, in the present invention, the thickness of the cover rubber layer is not particularly limited because it can be appropriately changed depending on the use in which the marine hose is used (for example, the type of fluid to be transported). When transporting a fluid containing a large amount, it is preferably about 5 to 15 mm.

The manufacturing method of a marine hose is not specifically limited, A conventionally well-known method can be used as a manufacturing method of a marine hose.
Specifically, a method in which the inner rubber layer, the reinforcing layer, the intermediate rubber, the buoyancy material layer, and the cover rubber layer are laminated in this order on a mandrel, and then vulcanized and manufactured is preferable. Is done.

  The hose of the present invention is provided with an inner rubber layer formed of the above-described rubber composition of the present invention, so that both oil resistance and cold resistance are excellent, and it can be used even in extremely cold regions.

The tank seal of the present invention is a tank seal comprising at least an outer surface rubber layer and a reinforcing layer, and the outer surface rubber layer is made of the above-described rubber composition of the present invention. By providing the outer surface rubber layer formed by the rubber composition of the present invention described above, both oil resistance and cold resistance are excellent, and it can be used even in extremely cold regions.
Specifically, a tank seal in a large floating roof type oil storage tank proposed by the present applicant in Japanese Patent Laid-Open No. 2001-48286 is preferably exemplified.

  The oil-resistant belt of the present invention is an oil-resistant belt comprising at least a cover rubber layer and a reinforcing layer, and the cover rubber layer is made of the rubber composition of the present invention described above. By providing the cover rubber layer formed by the rubber composition of the present invention described above, both oil resistance and cold resistance are excellent, and it can be used even in extremely cold regions.

  The rubber composition of the present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto.

(Examples 1-3, Comparative Examples 1-7)
Using 100 parts by mass of NBR 1 to 5 shown in Table 1 below (the numerical value in parentheses is the amount of bonded acrylonitrile), a composition component (part by mass) shown in Table 1 below was used, and 148 ° C. × 60 minutes. A test specimen was produced by press vulcanization under a vulcanization condition and a surface pressure of 3.0 MPa.
In Examples 1 and 2 and Comparative Examples 3 and 4, two types of NBR having different amounts of bonded acrylonitrile are contained. In any of the examples, the total amount of bonded acrylonitrile is 36%.

In addition, as each said composition component, what was shown below was used.
-NBR1 (44%): Nipol DN005 (manufactured by Nippon Zeon)
-NBR2 (41%): Nipol 1041 (manufactured by Nippon Zeon)
-NBR3 (33%): Nipol 1042 (manufactured by Nippon Zeon)
-NBR4 (29%): Nipol 1043 (manufactured by Nippon Zeon)
-NBR5 (33%): Nipol DN3335 (manufactured by Nippon Zeon)
・ Carbon black 1: FT (Asahi Carbon Corporation)
・ Carbon black 2: FEF (Mitsubishi Chemical Corporation)
・ Silica: Nip seal AQ (Tosoh Silica)
・ Siritin: Siritin Z86, manufactured by Hoffman Mineral Co., Ltd. ・ Zinc oxide: 3 types of zinc oxide (manufactured by Shodo Chemical Industries)
・ Stearic acid: Beads stearic acid (manufactured by NOF Corporation)
・ Anti-aging agent: RD (Ouchi Shinsei Chemical Co., Ltd.)
・ Plasticizer 1: Dioctyl adipate (Mitsubishi Kasei Vinyl)
・ Plasticizer 2: Dioctyl phthalate (manufactured by Nippon Nippon Chemical Co., Ltd.)
・ Sulfur: Oil-treated sulfur (Karuizawa Refinery)
・ Vulcanization accelerator: N-cyclohexyl-2-benzothiazolylsulfenamide (Noxeller CZ, manufactured by Ouchi Shinsei Chemical Co., Ltd.)
・ Retarder (scorch retarder): PVI (manufactured by FLEXSYS)

  The various test specimens obtained above were evaluated for the breaking strength, breaking elongation, JIS A hardness, oil resistance and cold resistance shown below. The results are shown in Table 1 and FIGS.

<Elongation at break, strength at break>
Punched No. 3 dumbbell-shaped test piece, tensile tensile test at a speed 500 mm / min is performed in conformity with JIS K6251-1993, strength at break (T _B) [MPa], and elongation at break (E _B) [% ] Was measured at room temperature.

<JIS A hardness>
About each dumbbell-shaped 3 type test piece similar to the above, JIS A hardness was measured according to JIS K6253-1997.

<Oil resistance>
The oil resistance was evaluated by immersing the obtained test specimens in a fluid (isooctane / toluene = 55/45 mixed solution) at room temperature for 1 week, breaking strength after breaking, breaking elongation, JIS A hardness, and before and after immersion. The volume change rate (%) was measured.

<Cold resistance>
Evaluation of cold resistance was performed by measuring the low temperature embrittlement temperature of the obtained various specimens. The low temperature embrittlement temperature was measured according to “Low Temperature Impact Embrittlement Test” of JIS K6261-1997.

From the results shown in Table 1 and FIGS. 4 to 6, the cured products composed of the rubber compositions obtained in Examples 1, 2 and 3 were cured from the rubber compositions obtained in Comparative Examples 3, 4 and 5, respectively. It can be seen that the oil resistance is equivalent or better and the cold resistance is more improved than that of the product.
On the other hand, from the results of Comparative Examples 6 and 7, it is necessary to reduce the amount of bound acrylonitrile from 33% to 29% in order to lower the low temperature embrittlement temperature by about 4 ° C. However, simply reducing the bound acrylonitrile. It can be seen that the volume change rate changes greatly, resulting in poor oil resistance. The balance between the cold resistance (low temperature embrittlement temperature) and the oil resistance is as shown in FIG.
Therefore, it can be seen that the effects of Examples 1 to 3 in which the cold resistance is improved while maintaining the oil resistance equal to or higher are very useful effects.

FIG. 1 is an external view showing an example of a preferred embodiment of the hose of the present invention. 2 is a cross-sectional view of a main part in the direction of arrows AA shown in FIG. FIG. 3 is a diagram illustrating the configuration of the reinforcing layer. FIG. 4 is a graph showing the relationship between the amount of bound acrylonitrile and the low temperature embrittlement temperature in the examples. FIG. 5 is a graph showing the relationship between the amount of bound acrylonitrile and the volume change rate in Examples. FIG. 6 is a graph showing the relationship between the low temperature embrittlement temperature and the volume change rate in the examples.

Explanation of symbols

10: Hose 11: Hose body 12: Mounting flange 112: Internal rubber layer 113: Reinforcing layer 113a: Cord 113b: Fastening wire 114: Intermediate rubber layer 114a: Body wire 114b: Fastening wire 115: Cover rubber layer 116: Buoyant material layer 121: Cylindrical part 122a, 122b, 122c: Ring part

Claims (8)

  A rubber composition for cold resistance containing acrylonitrile-butadiene rubber (NBR) and an aggregate of quartz and kaolinite.   The cold-resistant rubber composition according to claim 1, wherein a content of the aggregate is 1 to 100 parts by mass with respect to 100 parts by mass of the acrylonitrile-butadiene rubber (NBR).   The cold-resistant rubber composition according to claim 1 or 2, wherein the amount of bound acrylonitrile of the acrylonitrile-butadiene rubber (NBR) is 15 to 55 mass%.   The cold-resistant rubber composition according to any one of claims 1 to 3, wherein a content of the acrylonitrile-butadiene rubber (NBR) is 25 to 60% by mass.   Furthermore, carbon-resistant rubber composition in any one of Claims 1-4 which contains carbon black 10-150 mass parts with respect to 100 mass parts of said acrylonitrile-butadiene rubbers (NBR).   A hose comprising at least an inner rubber layer and a reinforcing layer, the inner rubber layer comprising the cold-resistant rubber composition according to any one of claims 1 to 5.   A tank seal comprising at least an outer rubber layer and a reinforcing layer, the outer rubber layer comprising the cold-resistant rubber composition according to any one of claims 1 to 5.   An oil-resistant belt comprising at least a cover rubber layer and a reinforcing layer, wherein the cover rubber layer is made of the cold-resistant rubber composition according to any one of claims 1 to 5.

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