JP2001343050A - Power transmission belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission belt in which an amount of wear in traveling motion is reduced by maintaining a heat resistance and a low temperature resistance and by lowering a thrust force. SOLUTION: In a V ribbed belt 1 comprising a elastic body layer including a bonded rubber layer 3 in which core wires are embedded longitudinally of the belt and a compressed rubber layer 4, an ethylene-α-olefin elastomer is used at least for the compressed rubber layer 4 out of the bonded rubber layer 3 and the compressed rubber layer 4, and S-twist rope and Z-twist rope are arranged alternately as a final twist for the core wire 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission belt, and more particularly, to using a specific ethylene-.alpha.-olefin elastomer for at least a compression rubber layer to maintain excellent heat resistance and cold resistance and to provide a thrust force. The present invention relates to a power transmission belt in which the amount of wear during running is reduced by reducing the power consumption.

[0002]

2. Description of the Related Art In recent years, due to social demands for energy saving and compactness, the ambient temperature around the engine room of an automobile has been increasing as compared with the related art. Accordingly, the operating temperature of the power transmission belt has been increasing. Conventionally, natural rubber, styrene-butadiene rubber, and chloroprene rubber have been mainly used for power transmission belts. However, in a high-temperature atmosphere, a problem has occurred in that a crack is generated in a cured compressed rubber layer at an early stage.

[0003] In response to such an early breakage phenomenon of the belt,
Improvement of the heat resistance of chloroprene rubber has been studied,
Although some improvements have been made, there is a limit as long as chloroprene rubber is used, and a sufficient effect has not yet been obtained.

[0004] For this reason, the use of rubbers having a highly saturated or completely saturated main chain, such as chlorosulfonated polyethylene rubber, hydrogenated nitrile rubber, and fluoro rubber, which are excellent in heat resistance, has been studied. . Of these, chlorosulfonated polyethylene has dynamic fatigue, abrasion resistance,
It is known that the oil resistance is equivalent to that of chloroprene rubber, but the water resistance is greatly affected by the vulcanization system, particularly the acid acceptor. Usually, oxides such as MgO and PbO have been used as acid acceptors for chlorosulfonated polyethylene.

However, PbO, Pb_Three O_Four Lead compounds such as
If the acid acceptor is used, a belt with good water resistance can be obtained.
However, use of lead compounds is preferred due to pollution and hygiene issues.
I don't. When MgO is used as an acid acceptor,
MgC generated during crosslinking reaction _l2 Remarkably water resistant
Damaged and belt adaptation was inadequate. Meanwhile, gold
Uses an epoxy acid acceptor as an acid acceptor other than the group oxide
If so, it is possible to obtain a composition having good water resistance
However, there is a problem that odor problems etc.
there were.

The power transmission belt has a significantly improved belt running life in a high-temperature atmosphere and excellent heat resistance as compared with a belt using chloroprene rubber, but has a low heat resistance of -30 ° C. or lower. It became clear that the belt running life under the atmosphere was inferior. The reason for this is that conventional chlorosulfonated polyethylene rubber is obtained by chlorosulfonating polyethylene and contains chlorine, so that the cohesion energy of chlorine increases at low temperatures and the rubber hardens in a low temperature range. This is presumed to be due to lack of rubber elasticity and easy cracking.

For this reason, it has recently been proposed to use, instead of chloroprene rubber, an ethylene-α-olefin elastomer reinforced with a metal salt of an α-β-unsaturated organic acid for a power transmission belt. JP-A-500930, JP-A-2000-26674, JP-A-2000-
No. 80224 and the like.

[0008]

However, ethylene-α-olefin elastomers such as ethylene-propylene-diene rubber have higher heat resistance than chloroprene rubber.
Because of its excellent cold resistance, belts using this elastomer are expected to dramatically improve durability.However, wear resistance is about the same as that of chloroprene rubber, so it may cause a failure due to rubber wear. In this case, a significant improvement in service life cannot be expected as compared with a chloroprene rubber belt.

[0009] Until now, polyester fibers have been used for the core wire, and twisting is often performed in consideration of dynamic fatigue properties. In many cases, either one of a Z twisted rope or an S twisted rope is used as the upper twist. Was. However, in this case, a thrust force is generated on the belt due to the twisting of the core wire while the belt is running, and the stresses received from the pulleys on both side surfaces of the belt are not uniform. There was a problem of missing.

The present invention addresses such a problem and provides a power transmission belt that maintains excellent heat resistance and cold resistance, and has reduced thrust force and reduced wear during running. .

[0011]

According to the first aspect of the present invention, there is provided a power transmission belt comprising an adhesive rubber layer having a core buried along a longitudinal direction of the belt and an elastic layer including a compression rubber layer. It is to use ethylene-α-olefin elastomer for at least the compression rubber layer of the adhesive rubber layer and the compression rubber layer, and to alternately arrange the S-twisted and Z-twisted ropes as core wires, and have excellent heat resistance. In addition, it is possible to finish the power transmission belt while maintaining cold resistance and reducing the thrust force to reduce the amount of wear during traveling.

According to the second aspect of the present invention, the power transmission belt is a V-ribbed belt comprising an adhesive rubber having a core buried along the longitudinal direction of the belt and a compression rubber layer having a plurality of rib portions extending in the circumferential direction of the belt. Thus, the V-ribbed belt maintains excellent heat resistance and cold resistance, and has a reduced thrust force to reduce wear during running.

According to the invention of claim 3 of the present application, in a power transmission belt composed of an adhesive rubber layer having a core wire buried along the longitudinal direction of the belt and an elastic layer including a compression rubber layer, at least the compression rubber layer has ethylene. A rubber layer obtained by adding 0.2 to 10 parts by weight of N, N'-m-phenylenedimaleimide to 100 parts by weight of an α-olefin elastomer, using a peroxide-cured rubber layer, and twisting the core as a core wire. S
This is a power transmission belt in which twist and Z twist ropes are alternately arranged.

According to a fourth aspect of the present invention, the power transmission belt is a V-ribbed belt comprising an adhesive rubber having a core buried in a longitudinal direction of the belt and a compression rubber layer having a plurality of rib portions extending in a circumferential direction of the belt. It is.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A V-ribbed belt 1 shown in FIG.
A cord 2 made of a high-strength, low-elongation rope made of polyester fiber, aramid fiber, or glass fiber is embedded in an adhesive rubber layer 3, and a compression rubber layer 4 as an elastic layer is provided below the core wire. are doing. The compressed rubber layer 4 is provided with a plurality of ribs 7 having a substantially triangular cross section extending in the longitudinal direction of the belt, and a rubber attached cloth 5 attached to the belt surface.

As another belt, a cut edge type V
Also used for the belt 21. As shown in FIG. 2, the belt 21 is composed of an adhesive rubber layer 24 in which a cord 23 is embedded and a compressed rubber 26. Further, each of the surface layers of the adhesive rubber layer 24 and the compressed rubber layer 26 has a canvas 22 with rubber. Are laminated.

The compressed rubber layers 4, 26 and the adhesive rubber layer 3,
The ethylene-α-olefin elastomer used for at least one of E.24 is ethylene-propylene rubber (E
PR), ethylene-propylene-diene terpolymer (EPDM) or a blend of these. Examples of diene monomers include dicyclopentadiene, methylene norbornene, ethylidene norbornene, 1,4-hexadiene, cyclooctadiene, and the like.

The diene component includes ethylidene norbornene, dicyclopentadiene, 1,4-hexadiene,
Non-conjugated dienes having 5 to 15 carbon atoms, such as cyclooctadiene and methylene norbornene.

The ethylene-α-olefin elastomer may have a different diene content, and the number of polymers to be blended is not limited. The blending may be performed between an ethylene-propylene-diene terpolymer containing a diene component and an ethylene-propylene copolymer containing no diene component.

The preferred ethylene-α-olefin elastomer used to prevent cohesive wear has an ethylene content of 50 to 75% by weight. If the ethylene content is less than 50% by weight, the amount of wear during running of the belt increases, and adhesive wear tends to occur. on the other hand,
If it exceeds 75% by weight, the cold resistance decreases due to crystallization of ethylene chains.

N, N 'as a peroxide co-crosslinking agent
-M-phenylenedimaleimide can be added. The addition amount of N, N'-m-phenylenedimaleimide is 0.2 to 10 parts by weight with respect to 100 parts by weight of the ethylene-α-olefin elastomer. When it is smaller, the effect of improving the wear resistance and the adhesive wear resistance is small. On the other hand, when it exceeds 10 parts by weight, the elongation of the vulcanized rubber is remarkably reduced, which causes a problem in the bending resistance.

Further, by adding 0.01 to 1 part by weight of sulfur to 100 parts by weight of the ethylene-α-olefin elastomer, a decrease in elongation of the vulcanized rubber can be controlled. If the amount exceeds 1 part by weight, the physical properties deteriorate, the abrasion during running of the belt is large, and the adhesive abrasion occurs.

The organic peroxide is usually a rubber,
Diacyl peroxide used for crosslinking of resin,
Peroxyester, diallyl peroxide, di-t
-Butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, 2.5-dimethyl-2
-5-di (t-butylperoxy) -hexyne-3,1
• 3-bis (t-butylperoxy-isopropyl) benzene, 1,1-di-butylperoxy-3,3,5-
Trimethylcyclohexane and the like, and those having a one-minute half-life by thermal decomposition of 150 to 250 ° C. are preferable. The amount of the ethylene-α-olefin elastomer 10
It is about 1 to 8 parts by weight, preferably 1.5 to 4 parts by weight based on 0 parts by weight.

Short fibers made of nylon 6, nylon 66, polyester, cotton, and aramid are mixed into the compressed rubber layers 4 and 26 to improve the lateral pressure resistance of the compressed rubber layers 4 and 26 and to make contact with the pulleys. Compressed rubber layers 4, 2
The surface of No. 6 is polished by a grinder to project the short fibers. The coefficient of friction of the surfaces of the compressed rubber layers 4 and 26 is reduced, and noise during belt running is reduced. Of these staple fibers, aramid staple fibers having rigidity, strength and abrasion resistance are most effective.

In order for the aramid short fiber to sufficiently exhibit the above-mentioned effects, the fiber length of the aramid fiber should be 1 to 20.
mm, the amount is 1 to 30 parts by weight based on 100 parts by weight of the ethylene-α-olefin elastomer. This aramid fiber has an aramid having an aromatic ring in the molecular structure,
For example, brand names Conex, Nomex, Kevlar,
Technora, Twaron, etc.

The compressed rubber layers 4 and 26 have an ethylene-α-olefin elastomer 1 as a matrix rubber.
With respect to 00 parts by weight, an ethylene-α-olefin elastomer and a fiber diameter of 1.0 μm or less, preferably 0.05 to
1 to 50 parts by weight, preferably 5 to 5 parts by weight of a micro-short fiber reinforced rubber graft-bonded with 0.8 μm micro-short fibers
25 parts by weight may be contained. If the blending amount of the short microfiber reinforced rubber is less than 1 part by weight, abrasion resistance is not sufficient, and if it exceeds 50 parts by weight, elongation of the rubber composition is reduced, and heat resistance and bending resistance are reduced.

In the short microfiber reinforced rubber, the ethylene-α-olefin elastomer constituting it is completely the same or similar to the ethylene-α-olefin elastomer of the matrix rubber of the compressed rubber layers 4 and 26.
Good bonding with matrix rubber. For this reason, since the ethylene-α-olefin elastomer and the short microfiber are chemically bonded between the short microfiber reinforced rubber and the matrix rubber, or even in the short microfiber reinforced rubber, cracks are formed in the compressed rubber layers 4 and 26. Difficult to penetrate, even if cracks occur.

The short microfiber reinforced rubber has a rubber component as a continuous phase in which the short microfibers are dispersed in a fine form, and the short microfibers form a strong chemical bond or interaction with the rubber component at the interface. ing. For this reason, the rubber layer containing this hardly cracks, and even if the cracks do not easily propagate. Moreover, the belt using this also has excellent heat resistance, cold resistance, bending resistance, and abrasion resistance.

The compressed rubber layers 4 and 26 may further include a reinforcing agent such as carbon black and silica, clay,
Various agents such as a filler such as calcium carbonate, a softener, a processing aid, an antioxidant, and a co-crosslinking agent such as TAIC may be added.

Also, nitrile rubber, hydrogenated nitrile rubber, hydrogenated nitrile rubber to which unsaturated carboxylic acid metal salt is added together with ethylene-α-olefin elastomer, chlorosulfonated polyethylene, chloroprene,
Urethane rubber, epichlorohydrin rubber, natural rubber, C
SM, ACSM and SBR can also be blended.

The hydrogenated nitrile rubber has a hydrogenation rate of 80% or more, and exhibits heat resistance and ozone resistance characteristics.
Preferably, 90% or more is good. A hydrogenated nitrile rubber having a hydrogenation rate of less than 80% has extremely low heat resistance and ozone resistance. In consideration of oil resistance and cold resistance, the amount of bound acrylonitrile is preferably in the range of 20 to 45%.

The chlorosulfonated polyethylene has a chlorine content of 15 to 35% by weight, preferably 25 to 32% by weight.
And a chlorosulfonated linear low-density polyethylene having a sulfur content in the range of 0.5 to 2.5% by weight.

For the cords 2 and 23, ropes such as polyethylene terephthalate fiber, polyester fiber (PEN fiber) having ethylene-2,6-naphthalate as a main constituent unit, aramid fiber and polyamide fiber are used. The twist and the Z twist rope are double-spun, and the S twist and the Z twist rope are alternately arranged. The number of twists of the S twisted rope is 7 to 18 times / 10 cm, and the number of twists of the Z twist rope is 7 to 18 times / 10 cm. Regarding the ply twist, either of them may be used and the direction may be opposite to or the same as that of the ply twist.

The twisted rope used is treated by the following method. (1) First, the untreated fiber twisted rope is immersed in a first treatment liquid set at room temperature with an isocyanate compound or / and an epoxy compound for 0.5 to 30 seconds, and then at 150 to 190 ° C.
2-5 minutes in oven adjusted to dry.

As the isocyanate compound used in the first treatment liquid, for example, 4,4′-diphenylmethane diisocyanate, tolylene 2,4-diisocyanate,
Examples include polymethylene polyphenyl polyisocyanate, hexamethylene diisocyanate, polyaryl polyisocyanate, and the like. This isocyanate compound is also used by being mixed with an organic solvent such as toluene and methyl ethyl ketone. Further, a blocked polyisocyanate in which an isocyanate group of the polyisocyanate is blocked by reacting a blocking agent such as a phenol, a tertiary alcohol, or a secondary alcohol with the above isocyanate compound can also be used.

The epoxy compound used in the first treatment liquid is, for example, a polyhydric alcohol such as ethylene glycol, glycerin or pentaerythritol, or a reaction product of a polyalkylene glycol such as polyethylene glycol and a halogen-containing epoxy compound such as epichlorohydrin. Object, resorcinol, bis (4-hydroxyphenyl)
Dimethylmethane, phenol. Formaldehyde resin,
Resorcinol. Reaction products with polyhydric phenols such as formaldehyde resins and halogen-containing epoxy compounds. The epoxy compound is used by being mixed with an organic solvent such as toluene and methyl ethyl ketone.

(2) The RFL liquid as the second processing liquid is a mixture of an initial condensate of resorcinol and formalin and NBR latex. In this case, the molar ratio of resorcinol to formalin is 3/1 to 1/3. Is preferable in increasing the adhesive strength. The initial condensate of resorcinol and formalin is mixed with rubber latex such that the resin content is 5 to 100 parts by weight with respect to 100 parts by weight of rubber of rubber latex, and the total solid concentration is 5 to 100 parts by weight. 4
Adjusted to 0% concentration.

In this case, the temperature of the treatment liquid was adjusted to 5 to 40 ° C., and the immersion time was 0.5 to 30 seconds.
It is heat-treated by passing it through an oven adjusted to ~ 250 ° C for 1-3 minutes.

(3) The third treatment liquid is obtained by adding a vulcanizing agent to a halogenated polymer and another adhesive rubber, and the halogenated polymer may be chloride rubber,
There are chloroprene rubber and chlorosulfonated polyethylene rubber. The bonding rubber is a rubber other than the halogenated polymer, and specifically, ethylene / α-
There are olefin rubber, NBR, SBR and the like, and ethylene / α-olefin rubber such as EPDM and EPT is preferable.

As the vulcanizing agent, dibenzothiazyl disulfide (MBTS), tetramethylthiuram disulfide (TMTD), N-cyclohexyl-2-benzothiazylsulfenamide (CBS), tetramethylthiuram monosulfide (TMTM) ), Mercaptobenzothiazole (MBT), PZ (ZnMDC) and the like. This vulcanizing agent improves the adhesive strength by vulcanization adhesion between the treated fiber rope and the ethylene / α-olefin rubber composition at 140 to 180 ° C.

The compounding ratio of the halogenated polymer and the bonding rubber in the third treatment liquid is from 3: 7 to 7: 3. Within this range, the adhesive strength is further improved. Moreover,
Within this range, the amount of solid adhesive adhering to the fiber rope after the adhesion is completed becomes 3 to 16% by weight, and not only the appearance of the rope is improved by preventing the adhesion of the residue to the rope, This is one of the steps of belt production, and eliminates the causes of rope climbing and rope opening during rope spinning.

The above-mentioned cover canvases 5, 22 are cloths woven into plain weave, twill weave, satin weave, etc. using yarns made of cotton, polyamide, polyethylene terephthalate, and aramid fibers. Of course, the cover canvas 5, 22 may not be used.

The rubber composition of the compressed rubber layers 4 and 26 used for the belts 1 and 21 may contain a carbon black, a plasticizer, an antioxidant and a processing aid which are generally used. There is no particular limitation on the method for mixing the above components, and for example, kneading can be appropriately performed by a known means and method using a Banbury mixer, a kneader, or the like.

An example of a method for manufacturing the V-ribbed belt 1 is as follows. First, on the peripheral surface of the cylindrical molding drum,
After winding a plurality of cover canvases and an adhesive rubber layer, a cord made of a rope is spirally spinned on this, and a compressed rubber layer is sequentially wound thereon to obtain a laminate, which is then vulcanized. To form a vulcanized sleeve. Next, the vulcanizing sleeve is hung on a driving roll and a driven roll, and is run under a predetermined tension, and the rotated grinding wheel is moved so as to contact the running vulcanizing sleeve to compress the vulcanizing sleeve. A plurality of 3 to 100 groove portions are ground on the surface of the rubber layer at a time.
The vulcanized sleeve obtained in this manner is removed from the drive roll and the driven roll, and the vulcanized sleeve is hung on another drive roll and the driven roll to travel, cut to a predetermined width by a cutter, and individually cut. Finish with a V-ribbed belt.

[0045]

The present invention will be described in more detail with reference to the following examples. Example 1 and Comparative Example 1 In this example, two plies of rubberized cotton canvas and an adhesive rubber layer composed of an EPDM composition were laminated on the peripheral surface of a cylindrical molding drum, and the twisted core shown in Table 1 was used as a core wire. A pair of polyester fiber ropes of S twist and Z twist with a pitch of 1.03 mm,
After double spinning with a tension of 5 kgf, a compressed rubber layer (shown in Table 2) composed of an EPDM composition containing short fibers is laminated, the laminated material is vulcanized, and a vulcanized sleeve is hung on a driving roll and a driven roll. While running under a predetermined tension, a rotating grinding wheel was applied to the surface of the compressed rubber layer to polish a plurality of grooves, and then cut to a predetermined width to obtain a V-ribbed belt. As Comparative Example 1, a twisted polyester fiber rope with a twist of Z was used as a core wire at a pitch of 1.0.
Spinning was performed at 3 mm and a tension of 5 kgf to obtain a V-ribbed belt.

The obtained V-ribbed belt is a K-type 3-ribbed belt having a length of 975 mm according to the RMA standard, a rib pitch of 3.56 mm, a rib height of 2.0 mm, a belt thickness of 4.3 mm, and a rib angle of 40 °.

Here, the compressed rubber layer was prepared from the rubber composition shown in Table 2, kneaded with a Banbury mixer, and then rolled with a calender roll. The compressed rubber layer contains short fibers and is oriented in the belt width direction. The adhesive rubber layer has a rubber composition obtained by removing cut yarns from the rubber compositions shown in Table 2.

[0048]

[Table 1]

[0049]

[Table 2]

The obtained V-ribbed belt was subjected to a thrust force, a wear test, a wear rate, a heat resistance test and a cold resistance test. The results are shown in Tables 2, 3, 4, and 5.

In the measurement of the thrust force, as shown in FIG. 3, the V-ribbed belt 1 is fixed to the driving side flat pulley 30 (diameter 70 mm) and the driven side flat pulley 31 (diameter 70 mm) such that the compressed rubber layer is in contact with the pulley surface. And rotated clockwise as viewed from the measurer side and in the opposite direction without load at 1,000 rpm, and the thrust force was measured by a load meter 32 disposed on one side of the belt. The thrust force is defined as a positive force when the belt approaches the measurer,
The result of the measurement was displayed.

In the abrasion test, a V-ribbed belt was driven by a driving pulley (120 mm in diameter) and an idler pulley (45 m in diameter).
m), set on a driven pulley (120 mm in diameter), and run for 24 hours at a load of the driven pulley of 12 horsepower, an installation load of the idler pulley of 85 kgf, and a rotation speed of 4,900 rpm, and a wear rate (wear weight / belt weight before running). Was examined.

The traveling tester used for the evaluation of the heat resistant traveling test includes a driving pulley (120 mm in diameter), a driven pulley (120 mm in diameter), and an idler pulley (70 m in diameter).
m) and a tension pulley (diameter: 45 mm). A belt is hung on each pulley of the testing machine, the ambient temperature is 120 ° C., the number of rotations of the driving pulley is 49.
The driven pulley was driven at 12 horsepower at 00 rpm, and the tension pulley was run with an initial tension of 57 kgf. The idler pulley engages on the back of the V-ribbed belt, and its winding angle is about 90 degrees. By this running test method, the time until cracks occurred in the rib portions of the belt was measured, and the heat resistance was compared.

In the evaluation method of the cold running test, a belt is hung on a driving pulley (140 mm in diameter), a driven pulley (45 mm in diameter), and a rear idler pulley (75 mm in diameter).
A load of 85 kgf is applied to the driven pulley, left for 18 hours at a rotation speed of 700 in an atmosphere of -40 ° C, run for 1 minute, then stopped for 2 minutes, and repeated until the belt is cracked. Was measured.

[0055]

[Table 3]

[0056]

[Table 4]

[0057]

[Table 5]

As a result, when the S and Z twists are alternately arranged, the thrust force is smaller than in the case of only the Z twist direction, and when the belt is suspended on the pulley, both sides of the compressed rubber are displaced. Since the stress from the pulley is more evenly received, the amount of wear during running of the belt is reduced, and the belt has excellent wear resistance.

Further, it can be seen that the belt of this embodiment has a high level of belt life even in a high-temperature atmosphere and a low-temperature atmosphere, and has both excellent heat resistance and cold resistance.

[0060]

As described above, according to the present invention,
Ethylene-α-olefin elastomer is used for at least the compression rubber layer of the adhesive rubber layer and the compression rubber layer, and the twisted S-twist and Z-twist ropes are alternately arranged as the core wire, so that heat resistance and cold resistance And the power transmission belt can be finished with reduced thrust force and reduced wear during traveling.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a V-ribbed belt according to the present invention.

FIG. 2 is a vertical sectional view of a V-cut edge type V-belt according to the present invention.

FIG. 3 is a schematic diagram of a method for measuring a thrust force of a belt.

[Explanation of symbols]

 Reference Signs List 1 V-ribbed belt 2, 23 core wire 3, 24 Adhesive rubber layer 4, 26 Compressed rubber layer 5, 22 Canvas with rubber 7 Rib 21 V belt

Claims (4)

[Claims] 1. A power transmission belt comprising an adhesive rubber layer having a core buried along a longitudinal direction of the belt and an elastic layer including a compression rubber layer, wherein at least one of the adhesive rubber layer and the compression rubber layer has a compression rubber layer. A power transmission belt comprising an ethylene-α-olefin elastomer and having twisted S-twisted and Z-twisted ropes alternately arranged as a core wire. 2. The power transmission belt according to claim 1, wherein the power transmission belt is a V-ribbed belt including an adhesive rubber having a core buried along the belt longitudinal direction and a compression rubber layer having a plurality of rib portions extending in a circumferential direction of the belt. Power transmission belt. 3. A power transmission belt comprising an adhesive rubber layer having a core buried along a longitudinal direction of the belt and an elastic layer including a compression rubber layer, wherein at least the compression rubber layer has an ethylene-α-olefin elastomer of 100 wt. 0.2 to 10 parts by weight of N, N'-m-phenylenedimaleimide
A power transmission belt comprising a weight-added, peroxide-cured rubber layer, and alternately arranging S-twisted and Z-twisted ropes as core wires. 4. The power transmission belt according to claim 3, wherein the power transmission belt is a V-ribbed belt including an adhesive rubber having a core buried along the belt longitudinal direction and a compressed rubber layer having a plurality of rib portions extending in a circumferential direction of the belt. Power transmission belt.