JP3421107B2 - Rubber composition and vulcanized rubber product obtained therefrom - Google Patents

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a chlorinated polyethylene rubber excellent in vulcanization adhesion to brass, which is useful for rubber / metal composite products used in fields where heat resistance and oil resistance are required, and Or maleic anhydride-modified chlorinated polyethylene rubber-based rubber composition, particularly used as an intermediate layer between the inner tube rubber, outer tube rubber and pressure-resistant steel wire layer of a heat-resistant high-pressure hose having a brass-plated pressure-resistant steel wire layer It relates to a rubber composition suitable for rubber. Further, it relates to a vulcanized rubber product obtained from the rubber composition, particularly to a steel wire reinforced heat resistant hose.

[0002]

2. Description of the Related Art Recently, tires, belts, moldings, rolls,
Many rubber products such as hoses have been used for a long time with oil heated under high temperature pressure, and deterioration of rubber products in such a state is always a serious problem.
This is because if the rubber product is severely deteriorated, it requires a lot of time and labor for maintenance and replacement, and the deterioration of the rubber product may cause a major accident.

Excellent oil resistance and at such high temperature (12
As a polymer that can withstand continuous use in an environment of 0 to 150 ° C., an acrylonitrile-butadiene copolymer rubber (N
BR), acrylic rubber (ACM), ethylene-acrylic rubber (AEM), ethylene-acrylic-vinyl acetate copolymer rubber (ER), chlorosulfonated polyethylene rubber (CSM), chlorinated polyethylene rubber (CM), and acrylonitrile- A rubber in which a conjugated diene portion of an acrylonitrile-based copolymer rubber such as a butadiene copolymer rubber (NBR) is hydrogenated is known. Among these polymers, chlorinated polyethylene rubber is a rubber having an excellent balance of various properties such as heat aging resistance, weather resistance, oil resistance and chemical resistance.

By the way, since chlorinated polyethylene rubber does not contain a double bond in its main chain, it cannot be vulcanized by ordinary sulfur, and in general, organic peroxides, thioureas and trithiocyanuric acid-based vulcanizates are used. A sulfurizing agent is used.

However, generally, vulcanized products of thioureas and diamines have low modulus, and vulcanized products of organic peroxides and trithiocyanuric acid have high modulus, but are vulcanized with metals such as brass. Due to poor vulcanization adhesiveness, in industrially using the chlorinated polyethylene rubber composition,
Its use range was extremely limited.

Therefore, the applicant has a high modulus,
And, as a chlorinated polyethylene rubber composition having excellent vulcanization adhesion to metals such as brass, chlorinated polyethylene rubber, magnesia, epoxy resin, triallyl isocyanurate, diallyl phthalate, trithiocyanuric acid and organic peroxides. A rubber composition containing a vulcanization system containing as an essential component has been proposed (Japanese Patent Publication No. 61-26820). However, although various properties of this rubber composition were improved as compared with the conventional ones, they were not sufficiently satisfactory.

[0007]

[Patent Document 2] Japanese Patent Application No. 02
-120708 and 02-126709, a vulcanization system comprising a dicyclohexylamine salt of 2-mercaptobenzothiazole, trithiocyanuric acid and a sulfur vulcanizing agent, 2,4,6-trimercapto-1,3.
The present applicant has proposed a vulcanization system in which the dicyclohexylamine salt of 5-triazine is the main vulcanizing agent, and has made use of the characteristics of the original chlorinated polyethylene rubber to further improve the adhesiveness with brass and provide a high modulus. Succeeded in giving a vulcanized product.

However, the vulcanized product obtained by such a vulcanizing system has no problem in an atmosphere up to about 130 ° C.
In a high temperature atmosphere of more than 0 ° C. and about 150 ° C., metal corrosion occurs and the adhesiveness lowers due to the corrosion.
For example, it could not withstand the use of high pressure hoses around automobile engines exposed to high temperatures.

On the other hand, in the past, steel wire reinforcement plated with brass has been generally used for high-pressure rubber hoses, but in order to have heat resistance, chlorosulfonated polyethylene (CSM) or chlorinated polyethylene is used. (CP
A heat-resistant rubber containing chlorine such as E) is used as the inner rubber or the outer rubber. Therefore, there is a problem that the heat-resistant rubber containing chlorine corrodes the steel wire plated with brass, and peeling of the rubber, pressure resistance and durability are deteriorated.

Thus, the first object of the present invention is to make good use of the heat aging resistance, weather resistance and oil resistance inherently possessed by chlorinated polyethylene rubber, and in addition, the adhesion to brass is excellent and metal corrosion does not occur even at high temperatures. It is to provide a rubber composition capable of giving a vulcanized product with a high modulus that does not occur, and a second object is to provide a vulcanized rubber product from the rubber composition.

[0011]

The first object of the present invention is to vulcanize the chlorinated polyethylene rubber and / or maleic anhydride-modified chlorinated polyethylene rubber (A) of the first embodiment of the present invention. The present invention also provides a rubber composition containing 2,4,6-trimercapto-1,3,5-triazine dicyclohexylamine salt (abbreviated as TDCA) as an agent and MgO and PbO as an acid acceptor. Of the second embodiment of chlorinated polyethylene rubber and / or maleic anhydride-modified chlorinated polyethylene rubber (A), and 2-mercaptobenzothiazole dicyclohexylamine salt (MDCA), trithiocyanuric acid and sulfur as vulcanizing agent components. As MgO as an acid acceptor
And a PbO rubber composition, respectively, and a second object of the present invention is a vulcanized rubber product from the rubber composition, particularly a steel wire reinforced heat resistant hose, which is the third aspect of the present invention. Achieved by That is, the steel wire-reinforced heat-resistant hose of the present invention comprises the rubber composition according to the first or second aspect of the present invention, which has excellent heat resistance in one or more rubber layers in contact with the steel wire and does not corrode the steel wire. use.

The structure of the present invention will be described in detail below, but the preferred embodiments of the present invention and advantages based on them will become apparent.

First Embodiment of the Invention Chlorinated polyethylene rubber and maleic anhydride modified chlorine
Polyethylene rubber In this embodiment, a chlorinated polyethylene rubber and / or a maleic anhydride-modified chlorinated polyethylene rubber (A) is used as a rubber component. By modifying the chlorinated polyethylene rubber with maleic anhydride, a rubber composition having excellent scorch stability can be obtained.

The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the chlorinated polyethylene rubber and / or maleic anhydride-modified chlorinated polyethylene rubber (A) usable in the present invention is usually 20 to 130, and the chlorine content is usually 5 to 5. The content of the unit derived from maleic anhydride in the case of being modified by 50% by weight and maleic anhydride is usually 0.01 to 5% by weight. Particularly, the maleic anhydride-modified chlorinated polyethylene (B) can be easily produced by chlorinating a polyethylene resin by a method known per se and then reacting with maleic anhydride, or vice versa. Further, it is commercially available, for example, under the trade name of Eraslen Super (Showa Denko KK) and can be easily obtained.

Vulcanization system In this embodiment, as the vulcanizing agent, 2,4 of the following formula (1) is used.
The dicyclohexylamine salt of 6-trimercapto-1,3,5-triazine (TDCA) is an essential component.

[0016]

[Chemical 1]

For the purpose of achieving sufficient vulcanization and ensuring heat resistance, the TDCA is usually 0.2 to 10 parts by weight, and particularly 0.1% to 100 parts by weight of the rubber (A). It is preferable to add 5 to 5 parts by weight.

In this embodiment, a dicyclohexylamine salt of 2-mercaptobenzothiazole (MDCA) represented by the following formula (2) can be further added.

[0019]

[Chemical 2]

Further, the above-mentioned TDCA and MD are used as vulcanizing agents.
A sulfur-based vulcanizing agent other than CA can be blended.

As the sulfur-based vulcanizing agent, powdered sulfur, highly dispersible sulfur, insoluble sulfur and the like, which are generally used as vulcanizing agents for rubber, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetrabutylthiuram disulfide. , Thiurams such as tetramethylthiuram monosulfide, dipentamethylenethiuram tetrasulfide, pentamethylenedithiocarbamic acid piperidine salt, pipecolyldithiocarbamic acid pipecoline salt, zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate,
Zinc N-ethyl-N-phenyldithiocarbamate, N
-Zinc pentamethylenedithiocarbamate, zinc dibenzyldithiocarbamate, sodium dimethyldithiocarbamate, sodium diethyldithiocarbamate,
Dithiocarbamate salts such as sodium dibutyldithiocarbamate, copper dimethyldithiocarbamate, ferric dimethyldithiocarbamate and tellurium diethyldithiocarbamate, zinc butylxanthate, zinc isopropylxanthate, xanthogenates such as sodium isopropylxanthate, N-cyclohexyl 2-benzothiazole sulfenamide, Nt-butyl-2-benzothiazole sulfenamide, N-oxydiethylene-2-benzothiazole sulfenamide, N, N-diisopropyl-2-benzothiazole sulfenamide, etc. And the thiazoles such as 2-mercaptobenzothiazole and dibenzothiazyl disulfide.

Of these, use of sulfur is particularly preferable. Of course, two or more of these may be used in combination.

When MDCA or a sulfur-based vulcanizing agent is contained, M
Since DCA and the sulfur-based vulcanizing agent have a synergistic effect with TDCA, the rubber composition has further excellent vulcanized rubber physical properties and vulcanization adhesion to metal such as brass. In addition, MDC as a vulcanizing agent
In a rubber composition containing A and a sulfur-based vulcanizing agent, TDC
Even if the A content is smaller, it is possible to obtain a rubber composition exhibiting desired vulcanized rubber physical properties and vulcanized adhesiveness with metal.

MDCA is usually 10 parts by weight or less with respect to 100 parts by weight of maleic anhydride-modified chlorinated polyethylene rubber (A), but 5 parts by weight or less when a sulfur-based vulcanizing agent is also added. preferable. If it is mixed in too much, the vulcanization adhesion to metals such as brass will deteriorate.

Acid Acceptor An important feature of the present invention is the combined use of MgO and PbO as acid acceptors. The present inventor has found that the reason why the vulcanized product of the rubber (A) corrodes the metal at high temperature is that hydrogen chloride is generated at high temperature. However, the compounding of, for example, an epoxy resin or synthetic hydrotalcite hinders the curing reaction of the vulcanization system of the present invention and cannot be used. Also, MgO
Alternatively, PbO alone does not have a function of preventing corrosion. However, the combined use of MgO and PbO has adhesiveness to metal, especially brass-plated steel, and effectively prevents corrosion of the steel and does not inhibit the curing reaction of the vulcanization system of the present invention.

The amount of MgO compounded is usually 5 to 30 parts by weight, preferably 8 to 20 parts by weight, based on 100 parts by weight of the rubber (A). The compounding amount of PbO is usually 5 to 30 parts by weight, and particularly preferably 8 to 20 parts by weight, based on 100 parts by weight of the rubber (A).

Other compounding agents In addition to the above compounding agents, in the first aspect of the present invention,
If necessary, a compounding agent such as a filler, a reinforcing agent, a plasticizer, an antiaging agent and a processing aid which are usually used may be added.

Second Aspect of the Present Invention Description of the chlorinated polyethylene rubber and / or maleic anhydride-modified chlorinated polyethylene rubber (A) in the first aspect of the present invention, and other compounding agents other than the vulcanizing agent Applies as is in the case of the second aspect. Hereinafter, the vulcanization system will be described in detail.

Vulcanization system In the present embodiment, a dicyclohexylamine salt of 2-mercaptobenzothiazole (MDCA) is used as a vulcanizing agent,
It contains trithiocyanuric acid and sulfur as essential components.

MDCA is represented by the above formula (2) and is usually 0.2 to 1 with respect to 100 parts by weight of the rubber (A).
It is preferable to use 0 part by weight, particularly 0.5 to 5 parts by weight.

Trithiocyanuric acid (E) is a compound represented by the following formula (3):

[0032]

[Chemical 3] It is preferable to add 0.2 to 10 parts by weight, and particularly 0.5 to 5 parts by weight to 100 parts by weight of the rubber (A).

Sulfur is powdered sulfur, highly dispersible sulfur,
Sulfur that is generally used as a vulcanizing agent for rubber, such as insoluble sulfur, can be used. The compounding amount is usually 0.05 to 5 parts by weight with respect to 100 parts by weight of the rubber (A),
It is particularly preferable to use 0.1 to 3 parts by weight.

In this vulcanization system, trithiocyanuric acid functions as a vulcanizing agent and MDCA functions as a vulcanization accelerator, and sulfur contributes to the improvement of vulcanization adhesion to a metal such as brass.

Third Aspect of the Invention A third aspect of the present invention relates to a vulcanized rubber product obtained by vulcanizing the compositions of the first and second aspects described above.

As the step of vulcanizing the above-mentioned composition to obtain a vulcanized rubber product, the step of obtaining an ordinary vulcanized rubber product can be adopted as it is.

That is, each component is kneaded to prepare an unvulcanized compounded rubber, which is molded into a desired shape, and then at 130 to 250 ° C.
A vulcanized rubber product can be obtained by heating and vulcanizing to the above temperature or by heating and vulcanizing at the above temperature at the same time as molding.

From the rubber composition of the present invention, a tire,
Many rubber products, such as belts, molds, rolls, and hoses, which are used for a long time under high temperature and high pressure environment and require oil resistance are manufactured. The vulcanized product obtained from the rubber composition of the present invention has excellent adhesiveness to brass, and thus is useful in the field of being vulcanized and integrated with a brass body to be a product.

Here, the brass body is used as a reinforcing material for ordinary rubber products, and refers to a wire material, a pipe material, a plate material or the like, and may be a steel material whose surface is brass-plated.

In particular, the vulcanized rubber product of the present invention is used as an intermediate rubber used between the inner tube rubber, outer tube rubber and pressure-resistant steel wire layer of a heat-resistant high-pressure hose having a brass-plated pressure-resistant steel wire layer. It is suitable.

As the vulcanized rubber product of the third aspect of the present invention, a steel wire reinforced heat resistant hose can be mentioned in particular. A preferred embodiment of this heat resistant hose is shown in FIG. 1 or FIG.
However, the heat resistant hose of the present invention is not limited to that shown in the drawings. The steel wire-reinforced heat-resistant hose 1 shown in FIG. 1 comprises a cylindrical rubber 2 and a reinforcing layer 4 composed of a steel wire layer coated on the outer surface thereof and an outer rubber 3 coated on the outer surface thereof. It is composed of an outer layer. Preferably the steel wire layer is brass plated. Further, the rubber layer in contact with the steel wire layer, that is, one or both of the inner surface rubber 2 and the outer surface rubber 3 is formed of a rubber layer obtained by vulcanizing the above-described rubber composition of the present invention. The steel wire-reinforced heat-resistant hose 5 shown in FIG. 2 is the hose 1 shown in FIG. 1 further having a reinforcing layer, and the first reinforcing layer 7 is provided on the inner rubber 6.
a is covered, the second reinforcing layer 7b is covered through the interlayer rubber 8, and the outer surface rubber 9 is covered as the uppermost layer. One or both of the first reinforcing layer and the second reinforcing layer is made of a steel wire layer, and the rubber layer in contact with these steel wire layers, that is, the inner surface rubber 6, the interlayer rubber 8 and / or the outer surface rubber 9 is provided in the above-mentioned invention. It is formed of a rubber layer obtained by vulcanizing the rubber composition. It is not necessary to form all the rubber layers with the rubber composition of the present invention, and only the surface in contact with the steel wire layer may be formed with the rubber composition of the present invention. Although not shown, a high-pressure hose formed of a rubber layer obtained by vulcanizing three or more reinforcing layers and the rubber composition of the present invention is also included in the hose of the present invention.

[0042]

EXAMPLES The present invention will be specifically described below with reference to examples. (Examples 1 to 20 and Comparative Examples 1 to 8) A rubber composition having the compounding components and compounding ratios (in parts by weight) shown in Tables 1, 3, and 5 was prepared and mixed with a mixing roll at 60 ° C. for 15 minutes. Then
An unvulcanized rubber composition was prepared and subjected to the following tests. Evaluation of each physical property was performed as follows. The vulcanizable unvulcanized rubber composition at a laboratory small rolls, 2.0 m
The sheet was taken out to a thickness of m. This sheet rubber was placed in a lab press molding machine at 165 ° C for 30 minutes at a surface pressure of 30.
The sheet was vulcanized under pressure at kgf / cm ² , and the properties of the sheet after vulcanization were observed to judge the vulcanizability. That is, vulcanizability ◯ ... vulcanization (curing) was observed vulcanizability × ... Progress of vulcanization was not observed, apparently unvulcanized. It was not submitted to the test.

Brass adhesion The unvulcanized rubber composition was treated with a small roll for a laboratory to 2.5 m.
The sheet was taken out to a thickness of m, and this rubber sheet was pressure-bonded to a brass plate. However, cellophane paper was placed on the part to be gripped by the chuck during peeling so that the upper and lower layers would not adhere to each other. Using a laboratory press molding machine, this is used at 165 ° C for 30 minutes.
It was vulcanized under pressure at a surface pressure of 30 kgf / cm ² and was integrally molded. After standing at room temperature for 24 hours, the integrally molded sample was cut into a width of 2.54 cm and subjected to a brass adhesion test.
The peeling force is measured in accordance with the method described in JIS K6301 8.3, which is a test in which rubber bonded to a metal piece is peeled in the direction of 90 degrees, using a tensile tester specified in JIS K6301 and a pulling speed of 50 mm. / Min.

Metal Corrosion The unvulcanized rubber composition was treated with a small laboratory roll to 2.5 m.
The sheet was taken out to a thickness of m, and this rubber sheet was pressure-bonded to a brass-plated steel plate. However, cellophane paper was placed on the part to be gripped by the chuck during peeling so that the upper and lower layers would not adhere to each other. This is 165 with a laboratory press molding machine.
Pressure vulcanization at a surface pressure of 30 kgf / cm ² for 30 minutes at ℃,
Molded and integrated. This molded and integrated sample is
SK6301 6. It was aged at 150 ° C. for 72 hours with a gear type aging tester specified in the air heating aging test. Then, it was left at room temperature for 24 hours, the state was observed, and a 2.54 cm width was cut out and evaluated in the same manner as in the brass adhesion test. The evaluation result was judged by the presence or absence of corrosion of the steel sheet. That is, metal corrosion resistance ○ ... No corrosion of steel plate Metal corrosion resistance × ... Corrosion of steel plate In addition, a decrease in peeling strength after aging was observed, and the notes were noted.

Normal physical properties The unvulcanized rubber composition was treated with a small roll for a laboratory at 2.0 m.
The sheet was taken out to a thickness of m. This sheet rubber was placed in a lab press molding machine at 165 ° C for 30 minutes at a surface pressure of 30.
Pressure vulcanization was performed at kgf / cm ² . This is JIS K6
Using a tensile tester specified in No. 301, pulling speed 500
Tensile strength, tensile strength, elongation at break and 1 at mm / min
The 00% modulus was measured and calculated. In addition, all measurement methods and calculations are in accordance with JIS K6301.3. It was conducted according to the method described in the tensile test. Furthermore, JIS K
6301 5.2 The hardness was measured according to the spring type hardness test (A type). The results are shown in Tables 2, 4 and 6.
It was shown to.

[0046]

[Table 1]

[0047]

[Table 2]

[0048]

[Table 3]

[0049]

[Table 4]

[0050]

[Table 5]

[0051]

[Table 6]

(Examples 21 and 22 and Comparative Examples 9 to 1)
2) The hoses shown in FIGS. 1 and 2 were made with the constitution shown in Table 7, the following characteristic tests were conducted, and the results are shown in Table 7. The reinforcing material used was a hard steel wire with a diameter of 0.31 mm plated with brass. The hose was manufactured by the following method. (1) Inner tube extrusion With a crosshead extruder, on a nylon mandrel,
An inner tube made of the rubber composition shown in Table 7 was extruded in the hose of Example 21 with an inner diameter of 9.2 mm and a wall thickness of 1.8 mm, and in the hose of Example 22 an inner diameter of 9.2 mm and a wall thickness of 2. Extruded with a size of 0 mm. (2) Reinforcement layer braiding Using a braiding machine, brass-plated pressure-resistant reinforcing steel wire having a diameter of 0.31 mm was braided. However, in the hose of Example 22, an interlayer rubber made of NBR-1 having a width of 60 mm and a thickness of 0.35 mm was applied between the first reinforcing layer and the second reinforcing layer. (3) Outer pipe extrusion Further, an outer pipe made of the rubber composition shown in Table 7 was formed by a crosshead extruder to have an outer diameter of 1 layer, 18.0,
The two layers were extruded with a size of 18.5 mm. (4) Vulcanization step The unvulcanized hose manufactured through the steps of (1) to (3) was leaded, vulcanized by a vulcanizing can, and then stripped. (5) Mandrel extraction step The mandrel was extracted from the vulcanized hose to obtain a predetermined hose. Breaking pressure A breaking test was performed according to the method described in JIS K6330 4.2.1 Pressure resistance test.

High temperature impulse test The high temperature impulse test was carried out according to the method described in JIS K6349 7.7 Impact Pressure Test (oil temperature 140 ° C., pressure 150 kg).
/ Cm ² , oil: Showa Ciel Sekiyu KK White Parrot S-3, 1 million times (total 240 hours), 2 million times (total 480 hours) and 3 million times (total 720 hours), after which the hose is connected. The steel wire was disassembled and the occurrence of discoloration rust of the steel wire was observed. At this time, visually check the state of the outer surface rubber with the rubber on the steel wire layer, and if the entire surface is covered with the outer surface rubber, 100% of the outer surface rubber is attached, and if there is no outer surface rubber at all,
%.

Outer rubber reinforced interlayer adhesion JIS K6301 7. It carried out according to the method described in the peeling test (ring shape).

Oil resistance JIS K6301 12. It was carried out according to the method described in the immersion test, and JIS No. It was immersed in the oil of No. 3 and the volume change rate (%) was measured.

[0056]

[Table 7]

[0057]

[Table 8]

Table 7 Note CM-8: Rubber composition prepared in Example 8 (Table 1) CM-ratio 6: Rubber composition prepared in Comparative Example 6 (Table 1)

[0059]

[0060]

[0061]

[0062]

The steel wire reinforced heat resistant hose of the present invention is oil resistant,
By using the rubber composition of the present invention, which has excellent heat resistance, it is possible to obtain a hose that does not corrode the brass-plated steel wire and has improved adhesive strength and excellent durability in a high temperature region. .

[0064]

The vulcanized rubber product obtained by vulcanizing the rubber composition of the present invention has the heat aging resistance and weather resistance originally possessed by chlorinated polyethylene rubber, and has a high modulus, and in combination with brass. Excellent adhesion, no metal corrosion even at high temperature. Therefore, from the rubber composition of the present invention, a rubber product such as a high-pressure hose for automobiles and hydraulics having a reinforced steel wire layer plated with brass in the middle is preferably produced.

[Brief description of drawings]

FIG. 1 is a perspective view showing a preferred embodiment of a steel wire reinforced heat resistant hose of the present invention.

FIG. 2 is a perspective view showing a preferred embodiment of the steel wire reinforced heat resistant hose of the present invention.

[Explanation of symbols]

1 Steel wire reinforced heat resistant hose 2 inner rubber 3 outer rubber 4 Reinforcement layer 5 Steel wire reinforced heat resistant hose 6 inner rubber 7a First reinforcing layer 7b Second reinforcing layer 8 Interlayer rubber 9 outer rubber

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C08K 5/36 C08K 5/36 5/47 5/47 F16L 11/04 F16L 11/04 (72) Inventor Takashi Sato Shi Kanagawa 2-1 Hiratsuka-shi, Prefectural Yokohama Rubber Co. Ltd. Hiratsuka Factory (58) Fields surveyed (Int.Cl. ⁷ , DB name) C08L 23/00-23/36 C08K 3/00-13/08 B32B 15/06 F16L 11/04

Claims (7)

(57) [Claims] 1. A chlorinated polyethylene rubber and / or a maleic anhydride-modified chlorinated polyethylene rubber (A) is added to 2,4,6-trimercapto-1,3,5-as a vulcanizing agent.
A rubber composition comprising a dicyclohexylamine salt of triazine (abbreviated as TDCA) and MgO and PbO as an acid acceptor. 2. The rubber composition according to claim 1, further comprising a dicyclohexylamine salt of 2-mercaptobenzothiazole (abbreviated as MDCA) as a vulcanizing agent. 3. The rubber composition according to claim 1, further comprising a sulfur-based vulcanizing agent other than TDCA and MDCA as a vulcanizing agent. 4. A chlorinated polyethylene rubber and / or a maleic anhydride-modified chlorinated polyethylene rubber (A) is treated with a dicyclohexylamine salt of 2-mercaptobenzothiazole (MDCA), trithiocyanuric acid and sulfur as a vulcanizing agent component. A rubber composition containing MgO and PbO as an acid agent. 5. A vulcanized rubber product obtained by vulcanizing the rubber composition according to claim 1. 6. The vulcanized rubber product according to claim 5, wherein the vulcanized rubber product has a metallic reinforcing layer, and the surface of the reinforcing layer is plated with brass. 7. The vulcanized rubber product is a high pressure hose.
Vulcanized rubber product described in.