JP2001003991A - Power transmission belt and method of manufacturing the same - Google Patents

Abstract

(57) [Summary] (Modified) [PROBLEMS] Dynamic bonding in which a compression rubber layer and an adhesive rubber layer are vulcanized and bonded, and a polyester core is bonded and embedded in the adhesive rubber layer. Manufactures power transmission belts with excellent productivity with high productivity. The adhesive rubber layer and the compressed rubber layer are both ethylene-containing.
An α-olefin-diene rubber compound vulcanizate, and the above-mentioned core wire is subjected to an adhesive treatment with a resorcin-formalin-latex adhesive composition, and is adhered and embedded in the adhesive rubber layer. In addition, the above resorcinol
A power transmission belt is provided, wherein 50 to 100% by weight of the solid content of the latex in the formalin-latex adhesive composition is at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene. .

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 a power transmission belt having a compressed rubber layer and an adhesive rubber layer, wherein the compressed rubber layer and the adhesive rubber layer are formed of an ethylene-α-olefin-diene rubber compound. The present invention relates to a power transmission belt made of a vulcanized product and having a core made of polyester fiber adhered and embedded in the adhesive rubber layer. Such a power transmission belt according to the present invention has excellent dynamic adhesion between the core wire and the adhesive rubber layer, and thus has a long dynamic life. Furthermore, the invention relates to a method for producing such a transmission belt.

[0002]

2. Description of the Related Art In general, a power transmission belt has a compression rubber layer and an adhesive rubber layer, and a fiber core is bonded and embedded in the adhesive rubber layer, and includes an upper surface, a lower surface, or side surfaces of the belt. A rubberized canvas is adhered to the entire peripheral surface as needed.

[0003] In such a power transmission belt, chloroprene rubber or a mixture of hydrogenated nitrile rubber and chlorosulfonated polyethylene rubber is generally used for the compression rubber layer, but recently, from the viewpoint of environmental protection, , Based on the demand for dechlorination,
Attempts have been made to use ethylene-α-olefin-diene rubber for the adhesive rubber layer as well as the compressed rubber layer.

[0004] However, ethylene-α-olefin-diene rubber has a disadvantage that its dynamic characteristics are inferior, as already known, and is particularly insufficient in fatigue resistance, wear resistance, tensile strength, elasticity and the like. In addition, the adhesiveness to the cord made of polyester fiber is not sufficient, and
Heretofore, it has been considered difficult to use a transmission belt in which dynamic characteristics are important.

Accordingly, the present inventors have proposed that the compression rubber layer and the adhesive rubber layer are both made of ethylene-α-olefin-diene rubber, and a core made of polyester fiber (hereinafter referred to as a polyester core) is used as the adhesive rubber layer. As a result of diligent research to obtain a power transmission belt having excellent dynamic characteristics that is adhered and embedded inside, its solid content, that is, its rubber component, is selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene. Excellent dynamic adhesion between the polyester core wire and the adhesive rubber layer by bonding the polyester core wire with a resorcinol-formalin-latex adhesive composition containing at least one rubber latex as a latex component. So that both the compression rubber layer and the adhesive rubber layer are ethylene-α The present inventors have found that a transmission belt having excellent dynamic characteristics can be obtained, which is made of an olefin-diene rubber and has a polyester core wire bonded and buried in an adhesive rubber layer, and has reached the present invention.

Further, according to the present inventors, when bonding a polyester core wire, a certain metal oxide and a sulfur-containing vulcanization accelerator are blended in the resorcinol-formalin-latex adhesive composition. By impregnating such a resorcinol-formalin-latex adhesive composition into a polyester core wire, heating and drying at a high temperature of 200 ° C. or more, and bonding the polyester core wire and the adhesive rubber layer. It has been found that it is possible to produce a power transmission belt comprising an ethylene-α-olefin-diene rubber having a polyester core wire with good productivity. It has been reached.

[0007]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above-mentioned problems in a power transmission belt made of ethylene-.alpha.-olefin-diene rubber. The present invention aims to provide a power transmission belt having excellent dynamic adhesiveness in which a polyester core wire is bonded and embedded in the adhesive rubber layer while the layers are vulcanized and bonded. It is an object of the present invention to provide a method capable of manufacturing a power transmission belt with high productivity.

[0008]

According to the present invention, a power transmission belt in which a compression rubber layer and an adhesive rubber layer are vulcanized and bonded, and a core made of polyester fiber is embedded in the adhesive rubber layer. In the above, both the adhesive rubber layer and the compressed rubber layer are made of a vulcanized product of an ethylene-α-olefin-diene rubber compound, and the core wire is subjected to an adhesive treatment with a resorcinol-formalin-latex adhesive composition, The adhesive is embedded in the adhesive rubber layer, and 50 to 100% by weight of the solid content (rubber component) of the latex in the resorcinol-formalin-latex adhesive composition is chlorosulfonated polyethylene and alkylated. A power transmission belt is provided which is at least one selected from chlorosulfonated polyethylene.

Further, according to the present invention, there is provided a method for manufacturing a power transmission belt in which a compression rubber layer and an adhesive rubber layer are vulcanized and adhered, and a core made of polyester fiber is embedded in the adhesive rubber layer. And a latex in which 50 to 100% by weight of the solid content (rubber component) in the latex is at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene. A core wire made of polyester fiber is impregnated with a resorcinol-formalin-latex adhesive composition containing a vulcanization accelerator, and 200 to 240 ° C.
Is performed, and the thus-treated core wire is placed between unvulcanized ethylene-α-olefin-diene rubber compound sheets for forming an adhesive rubber layer. The unvulcanized ethylene-α-olefin-diene rubber compound sheet is laminated on an unvulcanized ethylene-α-olefin-diene rubber compound sheet for forming a compressed rubber layer. The adhesive rubber layer and the compressed rubber layer, which are formed by pressurizing and heating and vulcanizing, are both made of a vulcanized product of an ethylene-α-olefin-diene rubber compound, and the core wire made of polyester fiber is in the adhesive rubber layer. The present invention provides a method for manufacturing a power transmission belt that is bonded and embedded in a power transmission belt.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a transmission belt is
It includes a V-ribbed belt and a V-ribbed belt.

FIG. 1 shows a cross-sectional view of an example of a V-ribbed belt. The upper surface of the belt is formed by a single layer or a plurality of layers of rubberized canvas 1, and adjacent thereto, an adhesive rubber layer 3 is formed. Are laminated. In this adhesive rubber layer, for example, a plurality of low elongation cords 2 made of polyester fibers are embedded so as to extend in the longitudinal direction of the belt at intervals.
Further, a compression rubber layer 5 is laminated adjacent to the adhesive rubber layer. The compressed rubber layer has ribs 4 spaced from each other so as to extend in the longitudinal direction of the belt. In many cases, short fibers 6 are oriented and dispersed in the width direction of the belt in the compressed rubber layer 5 in order to enhance the lateral pressure resistance.

FIG. 2 shows a cross-sectional view of an example of the V-belt. The upper surface of the belt is formed of a single layer or a plurality of layers of rubberized canvas 1 as described above. The upper rubber layer 7 is laminated, the adhesive rubber layer 3 in which the core wire 2 is buried in the same manner as described above is laminated adjacent thereto, and the compressed rubber layer 5 is further laminated adjacent thereto. . In many cases, the compressed rubber layer 5 has a
Short fibers 6 are oriented and dispersed in the width direction of the belt.
The compressed rubber layer is usually composed of a single layer or a plurality of layers of rubberized canvas 1
It is covered with.

In the power transmission belt according to the present invention, as described above, the compression rubber layer and the adhesive rubber layer are vulcanized and bonded, and a polyester core wire is bonded and embedded in the adhesive rubber layer. Accordingly, a rubberized canvas is adhered to the entire peripheral surface including the upper surface, the lower surface, or the side surface, and both the compressed rubber layer and the adhesive rubber layer are made of a vulcanized product of an ethylene-α-olefin-diene rubber compound.

In the present invention, as the ethylene-α-olefin-diene rubber, a rubber comprising a copolymer of an α-olefin other than ethylene and ethylene and a diene (non-conjugated diene), a partial halogen substitution product thereof, A mixture of two or more of α-
As the olefin, preferably, at least one selected from propylene, butene, hexene and octene is used. Among them, preferred ethylene-α-olefin-diene rubbers include ethylene-propylene-
Diene rubber, a partially halogenated product thereof, particularly a partially chlorinated product thereof, or a mixture of two or more thereof are preferably used.

In particular, in the present invention, ethylene-α-
As the olefin-diene rubber, for example, ethylene 50
-80% by weight, propylene 50-20% by weight, non-conjugated diene having an iodine value of 50 or less, preferably 4-40, and a Mooney viscosity ML _{1 + 4} (100 ° C.) of about 20-120 are preferable. Used. Although not particularly limited as the diene component,
Usually, a non-conjugated diene such as 1,4-hexadiene, dicyclopentadiene or ethylidene norbornene is appropriately used.

In the transmission belt according to the present invention, a polyester core wire is used as the core wire.
Polyethylene terephthalate and polyethylene naphthalate are preferably used. In addition, the polyester core wire has a resorcin-formalin-latex adhesive composition containing 50 to 100% by weight of solids as a latex component of a latex having at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene. (Hereinafter, sometimes referred to as an RFL adhesive composition), and is bonded and embedded in the adhesive rubber layer.

Chlorosulfonated polyethylene is a rubber obtained by reacting polyethylene with chlorine and sulfur dioxide, and has a chlorosulfonyl group as a vulcanization point. Usually, the chlorine content is in the range of 15 to 45% by weight, preferably 25 to 35% by weight, and the sulfur content is 0.5%.
In the range of ~ 2.5% by weight. Further, the alkylated chlorosulfonated polyethylene, in the chlorosulfonated polyethylene, reduces the amount of introduction of chlorine as a polar group,
Instead, an alkyl group is introduced to disturb the crystallinity of the molecule to achieve a balance between low-temperature characteristics (cold resistance) and rubber elasticity. The chlorine content is usually in the range of 25 to 30% by weight. And the sulfur content is 1% by weight or less, preferably 0.6 to
It is in the range of 0.8% by weight.

The RFL adhesive composition usually comprises resorcinol and formalin in a resorcinol / formalin molar ratio of 1/3.
Condensation in the presence of a basic catalyst at ~ 3/1 to prepare an aqueous solution of resorcinol-formalin resin (resorcinol-formalin precondensate, hereinafter referred to as RF) at a concentration of 5 to 80% by weight. It can be prepared by mixing rubber latex. In the RFL adhesive composition, the solid content concentration is not particularly limited,
Usually, it is in the range of 10 to 50% by weight.

According to the present invention, at least one kind of rubber selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene is used in an amount of 50 to 100% by weight, preferably 60 to 1% by weight, as a solid content of the latex component.
A polyester core wire is bonded with an RFL adhesive composition having a range of 00% by weight, and this is sandwiched between unvulcanized rubber sheets made of an ethylene-α-olefin diene rubber compound forming an adhesive rubber layer, This is laminated with an unvulcanized rubber sheet comprising an ethylene-α-olefin diene rubber compound forming a compressed rubber layer, heated and pressurized, and integrally vulcanized to obtain a transmission belt.

In the present invention, in order to bond the polyester core wire with such an RFL adhesive composition, for example, after immersing the polyester core wire in the RFL adhesive composition, the polyester core wire is preferably at 200 to 240 ° C., preferably at 200 to 240 ° C. 210-235 ° C
(Baking) to a temperature in the range of
The L adhesive composition is fixed to the polyester core wire. However, if necessary, after immersing the polyester core wire in the RFL adhesive composition, 150 to 200 ° C., preferably 1 to 200 ° C.
It may be heated (baked) to a temperature in the range of 70 to 200 ° C.

According to the present invention, the polyester core wire is RF
When performing the bonding treatment with the L adhesive composition, preferably, as a first (first) RFL treatment, the polyester core wire is first immersed in the first RFL adhesive composition, and then dried by heating. After performing one (first) RFL process,
Next, it is immersed in the second RFL adhesive composition, heated and dried, and subjected to the second (or final) RFL treatment, and thus, the treatment with the RFL adhesive composition is performed at least twice. Is preferred. In such a case,
The first and second RFL adhesive compositions may be the same or different. Further, if necessary, RFL
The treatment with the adhesive composition may be performed three times or more.

According to the present invention, the latex component in the RFL adhesive composition includes, as a rubber component, a second rubber together with at least one first rubber selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene. It may contain rubber. This second rubber is 2
-Chloro-1,3-butadiene-2,3-dichloro-1,3-
It is preferably a butadiene copolymer (DCB).

As described above, according to the present invention, the latex component in the RFL adhesive composition is selected from the group consisting of chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene together with at least one first rubber.
-Chloro-1,3-butadiene-2,3-dichloro-1,3-
When butadiene copolymer (DCB) rubber is included as the second rubber, the adhesion between the RFL adhesive composition and the polyester core is further strengthened, and thus the dynamic life of the resulting transmission belt. Can be further lengthened.

When the latex component in the RFL adhesive composition contains a second rubber, at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene is 50% by weight of the solid content. Above, preferably 55 to 95% by weight, particularly preferably 60 to 90% by weight,
2-chloro-1,3-butadiene-2,3-dichloro-1,3
50% by weight or less, preferably 5 to 45% by weight, particularly preferably 1% by weight of butadiene copolymer (DCB) rubber.
It is in the range of 0 to 40% by weight.

According to the present invention, as described above, an RFL adhesive composition containing a latex containing at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene as a main rubber component is used to prepare a polyester core wire. And then sandwiched between unvulcanized rubber sheets composed of an ethylene-α-olefin-diene rubber compound, vulcanized, vulcanized and bonded in an adhesive rubber layer, and embedded to obtain a polyester core wire. A high dynamic adhesion can be obtained between the adhesive layer and the adhesive rubber layer, and thus, the polyester core wire is integrally vulcanized and bonded into the adhesive rubber layer made of the ethylene-α-olefin-diene rubber compound. The transmission belt described has a high dynamic belt life.

However, according to the present invention, the RFL adhesive composition preferably further contains a certain metal oxide and a sulfur-containing vulcanization accelerator. As described above, the polyester core wire is impregnated with the RFL adhesive composition containing a certain metal oxide and a sulfur-containing vulcanization accelerator in addition to the above-described RF and latex, and then heated to 200 ° C. By heating to a high temperature and drying, the dynamic adhesion between the polyester core wire and the adhesive rubber can be further enhanced, and the time for the bonding process of the polyester core wire can be significantly shortened. -It is possible to produce a power transmission belt comprising an α-olefin-diene rubber compound, having a polyester core wire, and having excellent dynamic adhesiveness with high productivity.

Here, as the metal oxide, for example, zinc oxide, magnesium oxide, lead oxide or a mixture of two or more thereof is preferably used, and particularly, zinc oxide is preferably used. Further, as the sulfur-containing vulcanization accelerator, thiazoles, sulfenamides, thiurams,
Dithiocarbamates or a mixture of two or more thereof are preferably used. Such a sulfur-containing vulcanization accelerator works more effectively for accelerating the vulcanization of an ethylene-α-olefin elastomer than chlorosulfonated polyethylene or alkylated chlorosulfonated polyethylene.

The thiazoles include, for example, 2-
Mercaptobenzothiazole (M) and salts thereof (eg, zinc salt, sodium salt, cyclohexylamine salt, etc.), dibenzothiazyl disulfide (DM) and the like can be mentioned. Examples of sulfenamides include:
Examples of N-cyclohexyl-2-benzothiazylsulfenamide (CZ) include thiurams such as tetramethylthiuram monosulfide (T
S), tetramethylthiuram disulfide (TT), dipentamethylenethiuram tetrasulfide (TRA) and the like. Examples of dithiocarbamates include sodium di-n-butyldithiocarbamate (TP), dimethyl Examples thereof include zinc dithiocarbamate (PZ) and zinc diethyldithiocarbamate (EZ).

The mixing ratio to the RFL adhesive composition is RF
With respect to 100 parts by weight of the solid content of the latex component in the L adhesive composition, the metal oxide is usually in the range of 0.1 to 10 parts by weight, and the sulfur-containing vulcanization accelerator is usually 0.1 to 10 parts by weight. It is in the range of 1 to 20 parts by weight.

In particular, according to the present invention, together with a latex containing at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene in the range of 50 to 100% by weight of solids,
The resorcinol-formalin-latex adhesive composition containing the metal oxide and the sulfur-containing vulcanization accelerator is impregnated into a polyester core wire, heated to a temperature of 200 to 270 ° C., and dried to obtain high productivity. While securing, it is possible to achieve excellent dynamic adhesion between the adhesive rubber made of ethylene-α-olefin diene rubber and the polyester core wire.

According to the present invention, the polyester core wire is RF
Prior to treatment with the L adhesive composition, an isocyanate or epoxy treatment may be performed. That is, after immersing the polyester core wire in a solution containing an isocyanate compound or an epoxy compound, if necessary, by heating and drying,
The polyester core wire may be pre-treated.

The isocyanate compound is not particularly limited, but for example, tolylene diisocyanate, m-phenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, polymethylene polyphenyl polyisocyanate and the like are preferably used. Further, a polyhydric alcohol-added polyisocyanate obtained by reacting such an isocyanate compound with a compound having two or more active hydrogens in a molecule such as trimethylolpropane or pentaerythritol, or a phenol, A blocked polyisocyanate obtained by reacting a blocking agent such as a tertiary alcohol or a secondary amine to block an isocyanate group of the isocyanate compound can also be suitably used as the isocyanate compound.

On the other hand, if the epoxy compound is also a polyepoxy compound having two or more epoxy groups in the molecule,
Although not particularly limited, for example, polyhydric alcohols such as ethylene glycol, glycerin, sorbitol, and pentaerythritol, and polyalkylene glycols such as polyethylene glycol, and halogen-containing epoxy compounds such as epichlorohydrin Reaction of reaction products, polyhydric phenols such as resorcinol, bis (4-hydroxyphenyl) dimethylethane, phenol-formaldehyde resin, resorcinol-formaldehyde resin and phenolic resins with halogen-containing epoxy compounds such as epichlorohydrin The product is preferably used.

The solvent for forming the solution of the isocyanate compound or the epoxy compound is not particularly limited, either, and water or an appropriate organic solvent is used depending on the isocyanate compound or the epoxy compound used. Usually, the isocyanate compound is chemically very active, so that it is a non-aqueous solution.
As described above, those in which isocyanate groups are blocked by phenols or the like can be used as an aqueous solution. As the organic solvent, usually, benzene, xylene,
Aromatic hydrocarbons such as toluene, aliphatic ketones such as methyl ethyl ketone and methyl isobutyl ketone, ethyl acetate,
Aliphatic carboxylic acid alkyl esters such as amyl acetate are preferably used. The concentration of the isocyanate compound or the epoxy compound in such a solution is usually 5 to 50.
% By weight.

Further, in the present invention, after the polyester core wire is treated with the RFL adhesive composition, it may be treated with rubber paste. In the present invention, the rubber paste used for this post-treatment is usually a solution obtained by dissolving ethylene-α-olefin-diene rubber for forming a compression rubber layer and an adhesive rubber layer in an appropriate organic solvent. After the core wire is immersed in this solution, it may be dried by heating.

In the present invention, the ethylene-α-olefin-diene rubber compound may contain, if necessary, a filler such as carbon black, silica, glass fiber or ceramic fiber, or a filler such as calcium carbonate or talc. It may contain various agents used in the general rubber industry, such as agents, plasticizers, stabilizers, processing aids, and colorants.

The ethylene-α-olefin-diene rubber compound for forming the compression rubber layer and the adhesive rubber layer may be obtained by adding ethylene-α-olefin-diene rubber, if necessary,
It can be obtained by uniformly mixing with a medicine as described above using a usual mixing means such as a roll and a Banbury.

The power transmission belt according to the present invention can be manufactured by a conventionally known conventional method. For example, taking an example of a V-ribbed belt, after winding one or more rubber-coated canvas and an unvulcanized sheet for an adhesive rubber layer on the peripheral surface of a cylindrical forming drum having a smooth surface,
On this, a polyester core wire is spirally spun, and further, an unvulcanized sheet for an adhesive rubber layer is wound thereon, and then an unvulcanized sheet for a compressed rubber layer is wound to form a laminate, This is heated and pressurized in a vulcanizing can and vulcanized to obtain a cyclic substance. Next, a plurality of ribs are formed on the surface of the ring by a grinding wheel while running the loop under a predetermined tension while being stretched between a driving roll and a driven roll. Thereafter, the annular material is cut to a predetermined width while being run between another driving roll and a driven roll, and a V-ribbed belt as a product can be obtained.

[0039]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

In the following, a compound having the following composition was used as a compound for the adhesive rubber of the belt. Ethylene-propylene-diene rubber ¹⁾ 100 parts by weight HAF carbon (manufactured by Mitsubishi Chemical Corporation) 50 parts by weight Silica (Tokusyl Gu manufactured by Tokuyama Corporation) 20 parts by weight Paraffin oil (Sunflex 2280 manufactured by Nihon San Chemical Co., Ltd.) 20 parts by weight Vulcanizing agent (oil sulfur manufactured by Hosoi Chemical Co., Ltd.) 3 parts by weight Vulcanization accelerator (EP-150 ² manufactured by Ouchi Shinko Chemical Co., Ltd.) 2.5 parts by weight Vulcanizing aid (Kao ( 1 part by weight Vulcanization aid (Zinc oxide manufactured by Sakai Chemical Industry Co., Ltd.) 5 parts by weight Anti-aging agent (224 ³ manufactured by Ouchi Shinko Chemical Co., Ltd.) 2 parts by weight Anti-aging agent ( Ouchi Shinko Chemical Co., Ltd. MB ⁴⁾ ) 1 part by weight Tackifier (Nippon Zeon Co., Ltd. petroleum resin Quinton A-100) 5 parts by weight Short fiber (cotton powder) 2 parts by weight

The compound having the following composition was used as a compound for the compression rubber of the belt. Ethylene-propylene-diene rubber ¹⁾ 100 parts by weight HAF carbon (manufactured by Mitsubishi Chemical Corporation) 70 parts by weight Paraffin oil (Sunflex 2280 manufactured by Nippon San Chemical Co., Ltd.) 20 parts by weight Vulcanizing agent (manufactured by Hosoi Chemical Co., Ltd.) Oil sulfur) 1.6 parts by weight Vulcanization accelerator (EP-150 ²⁾ manufactured by Ouchi Shinko Chemical Co., Ltd. 2.8 parts by weight Vulcanization accelerator (Ouchi Shinko Chemical Co., Ltd. MSA ⁵ ) 1. 2 parts by weight Vulcanization aid (stearic acid manufactured by Kao Corporation) 1 part by weight Vulcanization aid (zinc oxide manufactured by Sakai Chemical Industry Co., Ltd.) 5 parts by weight Antioxidant (224 manufactured by Ouchi Shinko Chemical Co., Ltd.) ³⁾ ) 2 parts by weight Anti-aging agent (MB ⁴⁾ manufactured by Ouchi Shinko Chemical Co., Ltd. 1 part by weight Short fiber (66 nylon fiber, 6 de × 1 mm) 22 parts by weight

(Note) 1) Ethylene content of 56% by weight, propylene content of 36.1% by weight, ethylidene norbornene (E
NB) 5.5% by weight, dicyclopentadiene (DCPD)
2.4% by weight, Mooney viscosity ML _{1 + 4} (100 ° C.) 60 2) Vulcanization accelerator DM (dibenzothiazyl sulfide) and T
T (tetramethylthiuram disulfide) and EZ (mixture with zinc diethyldithiocarbamate) 3) TMDQ (2,2,4-trimethyl-1,2-dihydroquinoline) 4) 2-mercaptobenzimidazole 5) N-oxydiethylene -2-benzothiazylsulfenamide

Example 1 7.31 parts by weight of resorcinol and 10.77 parts by weight of formalin (37% by weight) were mixed and stirred, and an aqueous sodium hydroxide solution (0.33 parts by weight of solid content) was added thereto. Then, 160.91 parts by weight of water was added, the mixture was aged for 5 hours, and resorcinol-formalin resin (resorcinol-formalin precondensate) having a solid concentration of 6.40% by weight (this was
Called F. A) An aqueous solution was prepared. As shown in Table 1, chlorosulfonated polyethylene rubber (C
SM) latex was added and aged for 12 hours to obtain a resorcin-formalin-latex (RF) having a composition shown in Table 1.
L) An adhesive composition C was prepared.

(Preparation of Adhesion between Polyester Core Wire and Adhesive Rubber Layer and Measurement of Adhesive Strength) Next, a polyester filament is twisted into a strand, and the strand is twisted to form a polyester (polyethylene terephthalate) fiber core. I got This polyester core wire was immersed in a toluene solution of isocyanate (isocyanate solid content: 20% by weight), and then heated and dried at 240 ° C. for 40 seconds to perform a pretreatment.

Next, as shown in Table 2, the polyester core wire thus pre-treated was subjected to the first RFL treatment as follows.
First immersed in RFL adhesive composition C,
After heating and drying for 2 seconds, and then immersing in the same RFL adhesive composition C as above as a final RFL treatment,
For 80 seconds. Next, the polyester core wire thus treated is immersed in an adhesive solution obtained by dissolving the same ethylene-propylene-diene rubber as the adhesive rubber in toluene, and then heated and dried at 60 ° C. for 40 seconds to bond the polyester core wire to the polyester core wire. Was given.

The thus treated polyester core wire was sandwiched between unvulcanized sheets of the ethylene-propylene-diene rubber compound for the adhesive rubber, and these were pressed at a surface pressure of 3920.
It was pressurized and heated at kPa and a temperature of 160 ° C. for 35 minutes, followed by press vulcanization. The adhesive strength of the polyester core wire in the thus obtained adhesive was measured, and the mode of destruction in the adhesive when the adhesive strength was measured was observed. Table 2 shows the results.

(Production of Power Transmission Belt and Evaluation of its Dynamic Life) As described above, the rubber-coated canvas and the rubber compound for the adhesive rubber layer were not vulcanized on the peripheral surface of the cylindrical forming drum having a smooth surface. After winding the sheet, a polyester core wire was spirally spun on the sheet. Further, an unvulcanized rubber compound sheet for the adhesive rubber layer is wound thereon, and the unvulcanized rubber compound sheet for the compressed rubber layer is wound to form a laminate, which is subjected to an internal pressure of 6 kgf / cm
^2. Heat and pressurize in a vulcanizer under the conditions of an external pressure of 9 kgf / cm ² , a temperature of 165 ° C. and a time of 35 minutes, and perform steam vulcanization.
A ring was obtained. Next, the annular member is attached to a first drive system including a drive roll and a driven roll, and a plurality of ribs are formed on a surface thereof by a grinding wheel while running under a predetermined tension. The annular member is attached to a second drive system including a further driving roll and a driven roll, and is cut into a predetermined width while running, so that the product is V as a product having three ribs and a circumference of 1000 mm.
A ribbed belt was obtained.

The V-ribbed belt obtained in this way is connected to a driving pulley 11 (120 mm in diameter) as shown in FIG.
And driven pulley 12 (120 mm in diameter) and idler pulley 13 (70 mm in diameter) arranged between these pulleys
And a tension drive pulley 14 (55 mm in diameter). However, the back of the belt was engaged with the idler pulley.

At an ambient temperature of 110 ° C., the load of the driven pulley is set to 16 horsepower, the initial tension of the tension pulley is set to 85 kgf, and the driving pulley is rotated at 4900 rpm.
, And the running time until the cord was exposed from the belt or the rubber layer was cracked was defined as the dynamic life of the belt. Table 2 shows the results.

Example 2 As shown in Table 1, chlorosulfonated polyethylene rubber (CSM) latex and 2-chloro-1,3-butadiene-2,3-dichloro-1,3 were added to the same RF solution as in Example 1. A butadiene copolymer (DCB) latex was added, and the mixture was aged for 12 hours to give resorcin-formalin having the composition shown in Table 1.
Latex (RFL) adhesive composition D was prepared.

Next, the same polyester core wire as in Example 1 was immersed in a toluene solution of isocyanate (isocyanate solid content: 20% by weight), and then heated and dried at 240 ° C. for 40 seconds to perform pretreatment. Next, as shown in Table 2, as the first RFL treatment, the sheet was immersed in the RFL adhesive composition D, dried by heating at 220 ° C. for 80 seconds, and then the final RFL treatment was performed.
As the L treatment, after immersion in the same RFL adhesive composition D as above, it was dried by heating at 220 ° C. for 80 seconds. Next, the polyester core wire thus treated is immersed in an adhesive solution obtained by dissolving the same ethylene-propylene-diene rubber as the adhesive rubber in toluene, and then heated and dried at 60 ° C. for 40 seconds to bond the polyester core wire to the polyester core wire. Was given.

Next, the thus-treated polyester core wire was embedded in an unvulcanized sheet of ethylene-propylene-diene rubber for the adhesive rubber, and vulcanized in the same manner as in Example 1. The adhesive strength of the polyester core wire in the obtained adhesive was measured. Further, a V-ribbed belt was manufactured in the same manner as in Example 1, and the dynamic life was examined. Table 2 shows the results.

Comparative Example 1 As shown in Table 1, the same RF solution as in Example 1 was added with styrene-
A butadiene-vinylpyridine copolymer (VP) latex was added, and the mixture was aged for 12 hours to prepare a resorcinol-formalin-latex (RFL) adhesive composition A having a composition shown in Table 1.

Next, the same polyester core wire as in Example 1 was immersed in a toluene solution of isocyanate (isocyanate solid content: 20% by weight), and was heated and dried at 240 ° C. for 40 seconds to perform a pretreatment. Next, as shown in Table 2, as the first RFL treatment, the sample was immersed in the RFL adhesive composition A and dried by heating at 220 ° C. for 80 seconds.
As the L treatment, after immersion in the same RFL adhesive composition A as above, it was dried by heating at 220 ° C. for 80 seconds. Next, the polyester core wire thus treated is immersed in an adhesive solution obtained by dissolving the same ethylene-propylene-diene rubber as the adhesive rubber in toluene, and then heated and dried at 60 ° C. for 40 seconds to bond the polyester core wire to the polyester core wire. Was given.

Next, the polyester fiber thus treated was embedded in an unvulcanized sheet of ethylene-propylene-diene rubber for the adhesive rubber, and vulcanized in the same manner as in Example 1. The adhesive strength of the core wire in the obtained adhesive was measured. Further, in the same manner as in Example 1, V
A ribbed belt was manufactured and its dynamic life was examined. Table 2 shows the results.

Comparative Example 2 As shown in Table 1, chloroprene rubber (CR) latex was added to the same RF solution as in Example 1, and aged for 12 hours.
Resorcin-formalin-latex (RFL) adhesive composition B having the composition shown in Table 1 was prepared.

Next, the same polyester core wire as in Example 1 was immersed in a toluene solution of isocyanate (isocyanate solid content: 20% by weight), and then heated and dried at 240 ° C. for 40 seconds to perform a pretreatment. Next, as shown in Table 2,
As the first RFL treatment, the sheet is immersed in the RFL adhesive composition B, and dried by heating at 220 ° C. for 80 seconds.
As the L treatment, after immersion in the same RFL adhesive composition B as above, it was dried by heating at 220 ° C. for 80 seconds. Next, the polyester core wire thus treated is immersed in an adhesive solution obtained by dissolving the same ethylene-propylene-diene rubber as the adhesive rubber in toluene, and then heated and dried at 60 ° C. for 40 seconds to bond the polyester core wire to the polyester core wire. Was given.

Next, the thus-treated polyester core wire was embedded in an unvulcanized sheet of ethylene-propylene-diene rubber for the adhesive rubber, and vulcanized in the same manner as in Example 1. The adhesive strength of the polyester core wire in the obtained adhesive was measured. Further, a V-ribbed belt was manufactured in the same manner as in Example 1, and the dynamic life was examined. Table 2 shows the results.

[0059]

[Table 1]

[0060]

[Table 2]

Examples 3 to 8 As shown in Table 3, CSM was applied to the same RF aqueous solution as in Example 1.
An aqueous dispersion of a vulcanization accelerator DM (dibenzothiazyl disulfide) and zinc oxide was added together with the latex (and DCB latex), and the mixture was aged for 12 hours, followed by resorcinol-formalin-latex (RF
L) Adhesive compositions EJ were prepared.

Next, the same polyester core wire as in Example 1 was immersed in a toluene solution of isocyanate (isocyanate solid content: 20% by weight), and was heated and dried at 240 ° C. for 40 seconds to perform a pretreatment. Next, the polyester core wire thus pre-treated was immersed in the RFL adhesive composition shown in Table 4, subjected to the first RFL treatment, and dried by heating at 220 ° C. for 80 seconds. After immersion in the RFL adhesive composition shown and subjected to the final RFL treatment,
It was dried by heating for 0 seconds. Subsequently, the polyester core wire thus treated was treated with the same ethylene-propylene-
After being immersed in an adhesive solution obtained by dissolving diene rubber in toluene, the polyester core wire was dried by heating at 60 ° C. for 40 seconds to perform an adhesive treatment. Table 4 shows the results.

Next, the thus treated polyester core wire was embedded in the unvulcanized sheet of the ethylene-propylene-diene rubber for the adhesive rubber, and vulcanized in the same manner as in Example 1. The adhesive strength of the polyester core wire in the obtained adhesive was examined. Further, a V-ribbed belt was manufactured in the same manner as in Example 1, and the dynamic life was examined. Table 4 shows the results. In each case, the belt broke due to the exposure of the cord.

[0064]

[Table 3]

[0065]

[Table 4]

Examples 9 to 13 and Comparative Example 3 The same polyester core wire as in Example 1 was immersed in a toluene solution of isocyanate (isocyanate solid content: 20% by weight), and then heated and dried at 240 ° C. for 40 seconds to perform pretreatment. Was given. Next, this polyester core wire was subjected to RFL shown in Table 5.
It was immersed in the adhesive composition, subjected to the first RFL treatment, and dried by heating at a predetermined temperature for 80 seconds.
After being immersed in the L adhesive composition and subjected to the final RFL treatment, it was heated and dried at a predetermined temperature for 80 seconds. Next, the polyester core wire thus treated is immersed in an adhesive solution obtained by dissolving the same ethylene-propylene-diene rubber as the adhesive rubber in toluene, and then heated and dried at 60 ° C. for 40 seconds to bond the polyester core wire to the polyester core wire. Was given.

Next, the thus treated polyester core wire is embedded in an unvulcanized sheet of ethylene-propylene-diene rubber for the adhesive rubber, and vulcanized. The adhesive strength of the polyester core wire was measured. Further, a V-ribbed belt was manufactured in the same manner as in Example 1, and the dynamic life was examined. Table 5 shows the results
Shown in The stable tension is a tension of the belt when the belt is running stably.

According to the present invention, the polyester core is RF
After the L adhesive composition is impregnated, it is heated (baked) to a temperature in the range of 200 to 240 ° C. and dried, thereby realizing strong adhesion between the polyester core wire and the adhesive rubber layer, A power transmission belt having improved dynamic life can be obtained.

[0069]

[Table 5]

[0070]

As described above, in the power transmission belt according to the present invention, the compression rubber layer and the adhesive rubber layer made of the ethylene-α-olefin-diene rubber compound are all vulcanized and bonded. A polyester core is bonded and embedded in the layer. Here, the polyester core wire is used in a resorcinol-formalin-latex adhesive composition containing a latex in which at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene is 50 to 100% by weight of solids. And is buried in the adhesive rubber layer. According to such a power transmission belt of the present invention, strong dynamic adhesion is realized between the polyester core wire and the adhesive rubber layer, and the dynamic life is remarkably improved.

When bonding a polyester core wire with a resorcinol-formalin-latex adhesive composition, a resorcinol-formalin-latex adhesive containing a metal oxide and a sulfur-containing vulcanization accelerator according to the present invention. After the polyester core wire is impregnated by using the agent composition, the polyester core wire is heated to a temperature of 200 to 240 ° C. and dried (baked), so that an excellent dynamic movement between the polyester core wire and the adhesive rubber is obtained. Thus, high-performance power transmission belts having polyester core wires in the adhesive rubber layer can be manufactured with high productivity.

[Brief description of the drawings]

FIG. 1 shows a cross-sectional view of an example of a V-ribbed belt.

FIG. 2 shows a cross-sectional view of an example of a V-belt.

FIG. 3 is a diagram showing a belt drive system for performing a dynamic test of a power transmission belt.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rubberized canvas 2 ... Core wire 3 ... Adhesive rubber layer 4 ... Rib 5 ... Compressed rubber layer 6 ... Short fiber 7 ... Upper rubber layer 11 ... Drive pulley 12 ... Driven pulley 13 ... Idler pulley 14 ... Tension pulley

Claims (12)

[Claims] 1. A transmission belt in which a compression rubber layer and an adhesive rubber layer are vulcanized and bonded, and a core wire made of polyester fiber is embedded in the adhesive rubber layer. Are both made of a vulcanizate of an ethylene-α-olefin-diene rubber compound, and the above-mentioned core wire is subjected to an adhesive treatment with a resorcin-formalin-latex adhesive composition, and is bonded and embedded in the above-mentioned adhesive rubber layer. Wherein the solid content of the latex component in the resorcinol-formalin-latex adhesive composition is 50 to 50%.
A power transmission belt wherein 100% by weight is at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene. 2. The solid content of the latex component in the resorcin-formalin-latex adhesive composition is 50% by weight.
The above is at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene.
50% by weight or less of the solid content of the latex component is 2-chloro-1,3-butadiene-2,3-dichloro-1,3
The power transmission belt according to claim 1, wherein the power transmission belt is a butadiene copolymer rubber. 3. The rubber according to claim 1, wherein the ethylene-α-olefin diene rubber is a rubber comprising a copolymer of at least one α-olefin selected from propylene, butene, hexene and octene with ethylene and diene. Transmission belt. 4. The resorcinol-formalin-latex adhesive composition comprises 0.5 to 10 parts by weight of a metal oxide and 0.5 parts by weight of a sulfur-containing vulcanization accelerator per 100 parts by weight of a solid content of a latex component.
The power transmission belt according to claim 1, comprising 1 to 20 parts by weight. 5. The power transmission belt according to claim 4, wherein the metal oxide is zinc oxide, magnesium oxide or lead oxide. 6. The power transmission belt according to claim 4, wherein the sulfur-containing vulcanization accelerator is a thiazole, a sulfenamide, a thiuram, a dithiocarbamate or a mixture of two or more thereof. 7. A method for manufacturing a power transmission belt, wherein a compression rubber layer and an adhesive rubber layer are vulcanized and bonded, and a core wire made of polyester fiber is embedded in the adhesive rubber layer. Resorcinol-formalin-latex adhesive containing a metal oxide and a sulfur-containing vulcanization accelerator while containing 50 to 100% by weight of a latex that is at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene Impregnating the core composition made of polyester fiber with the agent composition;
An adhesive treatment including a step of heating to a temperature of 40 ° C. and drying is performed, and the core wire thus treated is placed between unvulcanized ethylene-α-olefin-diene rubber compound sheets for forming an adhesive rubber layer. The unvulcanized ethylene-α-olefin-diene rubber compound sheet is laminated on an unvulcanized ethylene-α-olefin-diene rubber compound sheet for forming a compressed rubber layer. The adhesive rubber layer and the compressed rubber layer are made of ethylene-
consisting of a vulcanizate of an α-olefin-diene rubber compound,
A method of manufacturing a power transmission belt in which a core made of polyester fiber is bonded and embedded in the adhesive rubber layer. 8. The solid content of the latex component in the resorcin-formalin-latex adhesive composition is 50% by weight.
The above is at least one selected from chlorosulfonated polyethylene and alkylated chlorosulfonated polyethylene.
50% by weight or less of the solid content of the latex component is 2-chloro-1,3-butadiene-2,3-dichloro-1,3
The method according to claim 7, which is a butadiene copolymer rubber. 9. The method according to claim 7, wherein the ethylene-α-olefin diene rubber is a rubber comprising a copolymer of at least one α-olefin selected from propylene, butene, hexene and octene with ethylene and diene. Manufacturing method of power transmission belt. 10. A resorcinol-formalin-latex adhesive composition comprising 0.5 to 10 parts by weight of a metal oxide and 100 parts by weight of a solid content of a latex component and a sulfur-containing vulcanization accelerator.
The method for producing a power transmission belt according to claim 7, comprising 0.1 to 20 parts by weight. 11. The method according to claim 7, wherein the metal oxide is zinc oxide, magnesium oxide or lead oxide. 12. The sulfur-containing vulcanization accelerator is a thiazole, a sulfenamide, a thiuram, a dithiocarbamate or a mixture of two or more thereof.
3. The method for manufacturing a power transmission belt according to item 1.