JP2018017398A - Transmission belt and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transmission belt capable of lowering a frictional coefficient of a reinforced cloth only by making small amount of friction coefficient reducing agent adhere to a surface, thereby improving abrasion resistance.SOLUTION: At least a part of a belt body surface constituting a transmission belt is coated with a fiber cloth containing graphenes, binder and cloth. The transmission belt is a transmission belt 1 including a tension band 2 being a belt body, and a plurality of blocks 10 arrayed at a pitch with a substantially equal interval in a length direction of the tension band and integrated with the tension band with fitting. On a surface of the tension band, contact parts between upper beam parts 11 and lower beam part 12 of the blocks are coated with the reinforced cloth.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a transmission belt provided with a reinforcing cloth that covers a belt surface and is required to have wear resistance, and a method for manufacturing the same.

  Transmission belts such as friction transmission belts and toothed belts are widely used as one of power transmission means. A typical form of these transmission belts has a structure in which a part of an elastomer such as rubber is covered with a reinforcing cloth, and while absorbing impact or suppressing noise by the flexibility of the elastomer, In order to suppress wear due to contact with a pulley made of a hard material such as metal, a reinforcing cloth is arranged on the contact surface with the pulley.

  For example, in a wrapped V belt, the entire outer periphery of the belt is covered with a reinforcing cloth, and in the low edge V belt, the upper and lower surfaces of the belt are often covered with a reinforcing cloth, and a toothed belt is a tooth surface that meshes with a pulley. And the back is often covered with a reinforcing cloth. Conventionally, short fibers have been provided on the friction transmission surface of the V-ribbed belt to reinforce and reduce the friction coefficient. However, in recent years, products having a reinforcing cloth disposed on the friction transmission surface are increasing. Further, in a resin block belt having a shape in which a number of resin blocks are coupled with a tension band, which is known as a high load transmission belt, reinforcing cloths are arranged on the upper and lower surfaces of the tension band that comes into contact with the resin block. .

  A common requirement for these reinforcing fabrics is to stabilize the wear resistance and friction coefficient at a low level. When the coefficient of friction is high, the friction transmission belt is difficult to be removed from the pulley, causing heat generation and noise. Further, in the toothed belt, the engagement with the pulley is not smoothly performed, which causes heat generation, vibration, and noise. Furthermore, in the resin block belt, when the belt enters and exits from the pulley, the block rotates with the portion where the block is fitted to the tension band as a fulcrum. Rubs and causes heat generation and wear.

  JP 2001-336583 A (Patent Document 1) is composed of para-aramid fibers on one side of a tension band, and includes at least two stages of a first treatment with resorcin, formalin, latex or isocyanate and a second treatment with rubber paste. A resin block belt in which a reinforcing cloth that has been subjected to an adhesive treatment is disposed is disclosed.

  However, in this resin block belt, the reinforcing cloth is formed of a material having high wear resistance, but the wear of the reinforcing cloth is reduced, but the wear of the block is promoted. When the block is worn, the engagement between the tension band and the block is loosened and rattling occurs, resulting in failure such as breakage of the block and cutting of the tension band.

  On the other hand, when the friction coefficient is reduced, heat generation and noise can be suppressed, and wear resistance can be improved, so that various proposals have been made.

  In JP-A-9-273603 (Patent Document 2), a reinforcing cloth is immersed in a rubber paste in which 30 to 70 parts by weight of molybdenum disulfide is added to 100 parts by weight of a polymer. A toothed belt is disclosed in which a tooth cloth layer containing molybdenum disulfide is laminated on the tooth surface.

  However, the effect of reducing the friction coefficient of molybdenum disulfide is not so great. When a small amount of molybdenum disulfide is added, a sufficient effect is not exhibited. On the other hand, when a large amount is added, the adhesive strength is lowered. Since the reduction in the adhesive strength reduces the durability of the belt, it is difficult for this belt to achieve both a reduction in the friction coefficient and the durability of the belt at a high level.

  In JP 2003-156103 A (Patent Document 3), a reinforcing cloth is dipped in a rubber paste in which 10 parts by weight of ultrahigh molecular weight polyethylene is added to 100 parts by weight of a polymer. There is disclosed a resin block belt in which a canvas layer coated with a coating rubber layer containing ultrahigh molecular weight polyethylene is formed on a contact surface with a block of a tension band. In the example of this document, it is described that no malfunction occurred in 600 hours under the high-speed durability running test conditions.

  However, even this resin block belt is not sufficiently durable, and the wear resistance is not sufficient in an actual machine in which a load is applied to the driven pulley.

  JP-A-2003-222197 (Patent Document 4) covers at least one surface of a tension band with a cover canvas containing a friction coefficient reducing agent dispersed at a ratio of 50 to 400 parts by mass in 100 parts by mass of an elastomer solid content. A resin block belt is disclosed. In this document, it is described that polytetrafluoroethylene (PTFE) is preferable as the friction coefficient reducing agent.

  However, when PTFE is blended in a large amount, adhesiveness and workability are lowered, and PTFE is expensive, but since the effect is not sufficiently exhibited in a small amount, the economic efficiency is also low.

  Japanese Unexamined Patent Publication No. 2003-322216 (Patent Document 5) discloses a toothed belt obtained by treating a tooth cloth with a treatment liquid containing 30 to 200 parts by weight of carbon nanotubes with respect to 100 parts by weight of a rubber component.

  However, it is necessary to mix a large amount of carbon nanotubes, and the cost is very low because it is very expensive.

JP 2001-336583 A (Claims) JP-A-9-273603 (Claims) JP 2003-156103 A (Claims, Examples) JP 2003-222197 A (claims, paragraphs [0027] and [0030]) JP 2003-322216 A (Claims 1 and 2)

  An object of the present invention is to provide a transmission belt that can reduce the friction coefficient of a reinforcing cloth and improve the wear resistance by simply attaching a small amount of friction coefficient reducing agent to the surface, and a method for manufacturing the same.

  Another object of the present invention is to provide a power transmission belt capable of reducing heat generation and noise during use and improving durability and a method for manufacturing the same.

  Another object of the present invention is to provide a power transmission belt excellent in adhesiveness and workability, and having high economic efficiency, and a method for manufacturing the same.

  As a result of intensive investigations to achieve the above-mentioned problems, the present inventor has reduced the friction coefficient of the reinforcing cloth by covering at least a part of the belt body surface of the transmission belt with a reinforcing cloth containing graphenes, a binder and a cloth. The inventors have found that the wear resistance can be improved and completed the present invention.

  That is, in the power transmission belt of the present invention, at least a part of the surface of the belt main body is covered with a reinforcing cloth including graphenes, a binder, and a cloth. The graphenes may be fixed via a binder between the surface of the fabric and / or between the fibers. At least a part of the graphenes may be exposed on the fabric surface, and the remaining graphenes may be uniformly present between the fibers in the fabric. The average particle size of the graphenes is about 0.1 to 3 μm. The binder may be a vulcanized rubber. The ratio of the graphenes is about 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder. The ratio of the graphenes is about 0.1 to 5 parts by mass with respect to 100 parts by mass of the fabric. The reinforcing cloth may further include a friction coefficient reducing agent other than graphenes. The binder may be the same vulcanized rubber as that of the belt body. The transmission belt of the present invention includes a tension band that is a belt body, and a plurality of blocks that are arranged at substantially equal intervals in the length direction of the tension band and that are integrated with the tension band by fitting. It is a power transmission belt, Comprising: At least the contact part with the upper side beam part and lower side beam part of the said block among the surfaces of the said tension | tensile_strength band may be coat | covered with the reinforcement cloth.

  The present invention also includes a method for manufacturing the power transmission belt including a reinforcing cloth precursor forming step of forming a reinforcing cloth precursor by fixing graphenes to the cloth via a binder precursor. In the reinforcing cloth precursor forming step, the cloth may be impregnated with a liquid composition containing graphenes and a binder precursor, and then dried. The production method of the present invention further includes a vulcanization step in which the binder precursor is an unvulcanized rubber, and at least a part of the surface of the belt body precursor containing the unvulcanized rubber is covered with a reinforcing cloth precursor and vulcanized. May be included.

  In the present invention, since at least a part of the belt main body surface of the transmission belt is coated with a reinforcing cloth including graphenes, a binder, and a cloth, the friction of the reinforcing cloth can be obtained only by attaching a small amount of the friction coefficient reducing agent to the surface. The coefficient can be lowered and the wear resistance can be improved. In particular, by reducing the friction coefficient of the reinforcing cloth, heat generation and noise during use can be reduced, and the durability of the belt can be improved. Furthermore, by using a small amount of friction coefficient reducing agent, it is possible to suppress an increase in material cost without impairing adhesiveness and workability.

FIG. 1 is a schematic perspective view showing an example of the resin block belt of the present invention. FIG. 2 is a cross-sectional view of the resin block belt in FIG. 1 in the width direction. FIG. 3 is a schematic view of blocks constituting the resin block belt of FIG. FIG. 4 is a side view in which a part of the resin block belt of FIG. 1 is omitted.

[Structure of transmission belt]
Hereinafter, the present invention will be described in detail with reference to the accompanying drawings as necessary.

  The transmission belt of the present invention is not particularly limited as long as at least a part of the surface of the belt main body is covered with a reinforcing cloth including graphenes, a binder, and a cloth. A flat belt, a V belt, a V-ribbed belt, and a wrapped V-belt. Friction power transmission belts such as low edge V belts, low edge cogged V belts, and resin block belts; meshing power transmission belts such as toothed belts may be used. Of these transmission belts, in belts other than the resin block belt, it is preferable that at least the contact surface with the pulley is covered with the reinforcing cloth. In the resin block belt, at least the contact surface of the tension band with the block is covered with the reinforcing cloth. It is preferable to coat with. Among these transmission belts, a wrapped V belt, a resin block belt, and a toothed belt are preferable, and a resin block belt is particularly preferable because it is used at a high load.

  The resin block belt has a structure including a tension band (center belt) and a plurality of blocks arranged at substantially equal intervals in the length direction of the tension band and integrated with the tension band by fitting. As long as it has, it has the same structure as a friction transmission belt called a conventional high-load transmission V-belt widely used in high-load transmission applications such as high displacement vehicles and scooters. .

  FIG. 1 is a schematic perspective view showing an example of a resin block belt, and FIG. 2 is a cross-sectional view in the width direction of the resin block belt of FIG. FIG. 3 is a schematic view of the blocks constituting the resin block belt of FIG. 1. Specifically, FIG. 3 is a plan view (a), a front view (b), a bottom view (c), and a side view (d) of each block. is there. FIG. 4 is a side view in which a part of the resin block belt of FIG. 1 is omitted.

  As shown in FIGS. 1 and 2, the resin block belt 1 includes two parallel endless tension bands 2 and a plate surface perpendicular to the longitudinal direction of the tension bands 2 (longitudinal direction of the belt). It is composed of a plurality of plate-like blocks 10 arranged at substantially equal intervals and integrated with the tension band 2. As shown in FIG. 3, each block 10 has the same shape and has a structure in which two upper beam portions 11 and lower beam portions 12 arranged in the vertical direction are connected by a center pillar portion 13 at the center in the belt width direction. The shape of the plate surface is substantially H-shaped. That is, the block 10 is formed with a pair of fitting grooves 14 surrounded by the upper and lower beam portions 11 and 12 and the center pillar portion 13. Each tension band 2 is press-fitted into each fitting groove 14 of each block 10 from both sides in the belt width direction, and each block 10 is integrated with the two tension bands 2.

  The length in the belt width direction of the upper beam portion 11 and the lower beam portion 12 of the block 10 is the longest at the upper end portion and shortens toward the lower end portion, and the shape in the belt width direction forms a substantially inverted trapezoidal shape. ing. When the resin block belt 1 is wound around each pulley, the upper beam portion 11 of each block 10 is positioned on the pulley outer diameter side with respect to the tension band 2, and the lower beam portion 12 is on the pulley inner diameter with respect to the tension band 2. Located on the side. That is, the side surface extending in the longitudinal direction of the belt is in contact with the pulley, and the tension band exposed on the side surface of the belt and the side surface portion of the block sandwiching the top and bottom of the exposed portion of the tension band form a friction transmission surface.

  As shown in FIGS. 1 and 4, concave grooves 21a and 21b extending in the belt width direction are formed on the outer peripheral surface and inner peripheral surface of each tension band 2 at a predetermined pitch in the belt longitudinal direction. Further, on the opposing surface in the vertical direction of the fitting groove 14 in each block 10, ridges 15a and 15b extending in the belt width direction are formed. In the resin block belt 1, the blocks 10 are fixed at a predetermined pitch along the longitudinal direction of the belt by engaging the ridges 15 a and 15 b of the block 10 with the grooves 21 a and 21 b of the tension band 2. The concave groove 21b on the inner peripheral surface of the tension band 2 is formed with a concave curved surface (semicircular cross section) having a gentle cross section compared to the concave groove 21a on the outer peripheral surface having a substantially square cross section. Therefore, the protrusion 15b of the fitting groove 14 that engages with the groove 21b is formed with a convex curved surface having a gentle cross section as compared with the protrusion 15a that engages with the groove 21a.

  Further, as shown in FIG. 3D, the thickness of each block 10 (length in the belt longitudinal direction) is formed with a constant thickness in the vertical direction in the upper beam portion 11 located on the pulley outer diameter side. The lower beam portion 12 located on the pulley inner diameter side is formed so that the thickness gradually decreases toward the lower side, which is the pulley inner diameter side.

  The resin block belt is not limited to the belt shown in FIGS. 1 to 4, and may be any resin block belt in which a plurality of blocks are fixed to the tension band in a state where a tension band extending endlessly in the belt longitudinal direction can be bent. Well (a resin block belt in which a plurality of blocks are connected in a caterpillar shape with respect to a tension band may be used), and a conventional high load transmission V-belt can be used.

  In the present invention, in such a resin block belt, at least the contact surface with the upper beam portion and the lower beam portion of the block among the surfaces of the tension band, that is, the center pillar portion of the block among the surfaces of the tension band. It is preferable that the surface other than the contact surface and the contact surface with the pulley (the left and right side surfaces of the resin block belt) is covered with a reinforcing cloth, and the contact surface with the center pillar portion of the block and / or the contact surface with the pulley is also reinforced. It may be covered with a cloth.

[Reinforcing cloth]
The reinforcing cloth includes graphenes, a binder, and a cloth. By covering at least a part of the surface of the belt main body, the friction coefficient of the reinforcing cloth can be lowered only by attaching a small amount of the friction coefficient reducing agent to the surface. Therefore, wear resistance can also be improved.

(Graphenes)
Graphene acts as a friction coefficient reducing agent (solid lubricant), and can reduce the friction coefficient in a small amount compared to conventional solid lubricants. The slidability and durability of the transmission belt can be compatible.

  The graphenes include a graphene sheet that is a single sheet usually referred to as “graphene” and a graphene film (multilayer graphene) that is a laminate of the graphene sheets.

The graphene sheet is a material constituting graphite, and is a sheet (single layer sheet) of sp ² bonded carbon atoms having a thickness of 1 atom. The structure has a hexagonal lattice structure (honeycomb structure) like a honeycomb formed from carbon atoms and their bonds.

  The graphene film is obtained by exfoliating graphite, is a thin laminate compared with graphite, and has a crystal structure. The number of graphene sheets stacked in the graphene film is, for example, about 2 to 20, and preferably about 3 to 10.

  The aspect ratio (average diameter / average thickness of the plate surface) of the graphene film may be 20 or more, for example, about 20 to 100,000, preferably about 50 to 30,000, and more preferably about 100 to 10,000. The average thickness of the graphene film may be, for example, about 1 to 10 nm, preferably about 1.5 to 5 nm.

  The graphenes may contain graphene oxide or may be formed of only graphene oxide.

  The shape of the graphenes (secondary aggregates) is not particularly limited, and examples thereof include a sheet shape, a granular shape (powdered shape or an indefinite shape), a combined shape of a sheet shape and a granular shape, and the like. Of these shapes, granular is preferable because it is easy to handle and easily disperses uniformly in the binder and fabric.

  When the graphenes are granular, the average particle diameter of the graphenes may be 50 μm or less, and has an average particle diameter smaller than the fiber diameter of the fibers constituting the fabric from the viewpoint of being easily dispersed in the fabric. For example, it is about 0.01-50 micrometers (for example, 0.1-30 micrometers), Preferably it is 0.03-10 micrometers, More preferably, it is about 0.05-5 micrometers (especially 0.1-3 micrometers). If the average particle size is too large, aggregates are likely to be formed in the binder, and it may be difficult to disperse uniformly.

  In the present specification and claims, the average particle diameter of graphenes was observed with a scanning electron microscope (“JSM-5900LV” manufactured by JEOL Ltd.) at a magnification of 5000 times, and was randomly selected. The extracted 20 particle sizes can be measured and averaged.

  Graphenes can be produced by a conventional method, and may be produced, for example, by the method described in Japanese Patent No. 5688669, Japanese Patent No. 5697067, Japanese Patent Publication No. 2015-501873, WO2013 / 146213 pamphlet, and the like.

  The ratio of graphene can be selected from the range of about 0.1 to 100 parts by mass (particularly 0.5 to 30 parts by mass) with respect to 100 parts by mass of the binder, for example, 0.5 to 10 parts by mass, preferably 1 to 1 part by mass. It may be about 8 parts by mass, more preferably about 3 to 7 parts by mass (particularly 4 to 6 parts by mass). In the present invention, the graphenes may be included as the friction coefficient reducing agent (first friction coefficient reducing agent), but a friction coefficient reducing agent (second friction coefficient reducing agent) other than graphenes is included. When high adhesiveness and workability are required or when graphene is combined with a second friction coefficient reducing agent (solid lubricant), the proportion of graphene is, for example, 0.3 to 8 parts by mass. The amount is preferably about 0.5 to 5 parts by mass, more preferably about 0.6 to 3 parts by mass (particularly 0.8 to 2 parts by mass). The proportion of graphene is, for example, 0.01 to 30 parts by mass, preferably 0.1 to 5 parts by mass, more preferably 0.15 to 4 parts by mass (particularly 1 to 3 parts by mass) with respect to 100 parts by mass of the fabric. ) If the proportion of graphene is too small, the effect of reducing the friction coefficient may be reduced. If the proportion is too large, the adhesiveness and workability may be reduced, and the appearance of the product may be reduced. Mixing becomes difficult, and there is a possibility that the adhesiveness to the fabric may be lowered.

  The graphenes may be contained in the reinforcing cloth, but from the point that the friction coefficient can be reduced, it is preferable that the graphenes are present (exposed to the outer surface) at least on the outer surface (such as the transmission surface) of the fabric. From the viewpoint of excellent durability, it is particularly preferable that it exists on the surface and inside (between fibers) of the fabric (particularly, it exists uniformly on the surface by being uniformly present inside).

  Graphenes are often coated with a thin film of binder on the surface of the reinforcing fabric, and the reinforcing fabric is used as a transmission surface (contact surface with the upper and lower beam portions of the block in the tension band of the resin block belt, and others. In the case of covering the contact surface of the belt with the pulley), the graphenes are exposed on the surface of the reinforcing cloth by contact with the block and the pulley immediately after the belt travels. In this case, the area ratio of the exposed graphenes with respect to the entire surface of the reinforcing cloth (the outer surface not in contact with the belt main body) may be 0.1% or more with respect to the entire surface, for example 0.1 -50%, preferably 0.3-20%, more preferably about 0.5-10%. If the area ratio of the graphenes is too small, the friction coefficient reducing effect (slidability) may be reduced. In the present invention, the area ratio of graphenes can be measured based on a scanning electron microscope (SEM) photograph.

(binder)
The graphenes may be fixed to the surface of the fabric and / or between the fibers (inside) via a binder, and particularly fixed to at least the outer surface (power transmission surface) from the viewpoint of excellent slidability. It is preferable to be fixed between the outer surface and the fiber because it is excellent in durability. Therefore, the binder is preferably attached to at least the surface of the fabric, and particularly preferably attached to the surface and the interior (between fibers) of the fabric (particularly, evenly adhered to the surface by being uniformly adhered to the inside). .

  The binder may be a polymer component such as an adhesive resin, but from the viewpoint of excellent adhesion to a belt body (a rubber layer of a tension band of a resin block belt, a compression layer or an extension layer of a V-ribbed belt), A vulcanized rubber is preferable, and a vulcanized rubber that is the same as or similar to the vulcanized rubber that forms the belt body (particularly the same) is particularly preferable. For example, if vulcanized rubber is used on a transmission surface (contact surface with the upper and lower beam portions of the block in the tension band of the resin block belt, contact surface with a pulley on another transmission belt, etc.), graphenes It is possible to prevent the effect of reducing the friction coefficient from disappearing at an early stage due to the fact that the resin is washed away by water and detached from the transmission surface, or missing at the beginning of running due to contact wear with the block or pulley. Graphenes can be held for a long time on the surface layer on the contact side with the pulley.

  Such a reinforcing cloth containing vulcanized rubber is fixed in a state where graphenes are integrated with the vulcanized rubber, and when the transmission surface is formed with the reinforcing cloth, the rubber thin film on the transmission surface is formed at the beginning of the belt running. When scattered, graphenes are exposed. In this state, when the vehicle continues to run while in contact with the block or pulley of the resin block belt, the graphenes are caused to flow through the water compared to the case where the graphenes adhere to the transmission surface after vulcanization of the belt. The risk of detachment from the surface or loss of the effects of graphenes due to contact friction with the block or pulley at the initial stage of travel is greatly reduced. Therefore, the graphenes fixed in an integrated state with the transmission surface can be held without disappearing in the running process, and the friction coefficient can be reduced, and furthermore, the friction coefficient can be reduced with a small amount. Durability can also be improved. Furthermore, the graphenes can be sustained for a long time by being held on the belt body for a long time.

  As the rubber component of vulcanized rubber, depending on the type of belt, taking into account wear resistance, heat resistance, sound resistance, transmission performance, adhesive strength, tackiness, dispersibility of graphenes, etc., known rubber components And / or elastomers such as diene rubbers (natural rubber, isoprene rubber, butadiene rubber, chloroprene rubber, styrene butadiene rubber (SBR), acrylonitrile butadiene rubber (nitrile rubber), hydrogenated nitrile rubber (hydrogenated nitrile rubber). And ethylene-α-olefin elastomer, chlorosulfonated polyethylene rubber, alkylated chlorosulfonated polyethylene rubber, epichlorohydrin rubber, acrylic rubber, silicone rubber, urethane rubber And fluororubber. These rubber components can be used alone or in combination. Among these rubber components, diene rubber (natural rubber, chloroprene rubber, hydrogenated nitrile rubber, etc.), ethylene-α-olefin elastomer (ethylene-propylene copolymer (EPM), ethylene-propylene-diene terpolymer) (Ethylene-α-olefin rubber such as EPDM) is preferable, and the resin block belt may be hydrogenated nitrile rubber.

  The hydrogenated nitrile rubber may be a combination of a hydrogenated nitrile rubber and a mixed polymer of a hydrogenated nitrile rubber and an unsaturated carboxylic acid metal salt, and the mass ratio of both is the former / the latter = 10/1 to 1 / 10, preferably 2/1 to 1/2, more preferably about 1.5 / 1 to 1 / 1.5.

(Fabric)
Examples of the fabric include fabric materials such as woven fabric, knitted fabric (weft knitted fabric, warp knitted fabric), and non-woven fabric. Among these, a woven fabric woven in a form such as plain weave, twill weave, satin weave, a woven fabric knitted at a wide angle such that the crossing angle between the warp and the weft exceeds 90 ° and 120 ° or less, a knitted fabric, etc. are preferable. Woven fabrics widely used as cover fabrics for transmission belts for general industries and agricultural machinery [Plain woven fabrics where the crossing angle between the warp and weft is a right angle, the crossing angle between the warp and weft exceeds 90 ° and 120 ° A plain woven fabric (wide angle canvas)] having a wide angle of the following degree is particularly preferable.

Examples of fibers constituting the fabric include polyolefin fibers (polyethylene fibers, polypropylene fibers, etc.), polyamide fibers (polyamide 6 fibers, polyamide 66 fibers, polyamide 46 fibers, aramid fibers, etc.), polyalkylene arylate fibers [polyethylene terephthalate]. (PET) fiber, poly C _2-4 alkylene C _6-14 arylate fiber such as polyethylene naphthalate (PEN) fiber, etc.], vinyl alcohol fiber (polyvinyl alcohol, ethylene-vinyl alcohol copolymer fiber, vinylon fiber, etc.) Etc.), synthetic fibers such as polyparaphenylene benzobisoxazole (PBO) fibers; natural fibers such as cellulosic fibers and wool; and inorganic fibers such as carbon fibers. These fibers may be single yarns used alone, or may be blended yarns in which two or more types are combined.

  Among these fibers, an aramid fiber is preferable from the viewpoint of excellent wear resistance, and excellent in stretchability. In the resin block belt, an aliphatic polyamide fiber is excellent in conformity to the shape of the fitting groove of the block. Polyamide fibers such as are preferred. When the aramid fiber or the polyamide fiber is included, the ratio of the aramid fiber or the polyamide fiber may be 50% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, based on the whole fiber. It may be 100% by mass.

  The average fiber diameter of the fibers constituting the fabric is, for example, about 3 to 150 μm, preferably about 5 to 100 μm, and more preferably about 10 to 80 μm. If the fiber diameter is too small, the holding power and uniform dispersion of the graphenes may be difficult, and the flexibility of the belt may be reduced. If it is too large, the mechanical strength of the reinforcing cloth may be reduced.

The basis weight of the fabric (raw material fabric) is, for example, about 100 to 500 g / m ² , preferably about 150 to 400 g / m ² , and more preferably about 200 to 350 g / m ² . If the basis weight is too large, the flexibility of the belt may be lowered, and if it is too small, the amount of graphene supported may be lowered, and the reinforcing effect of the reinforcing cloth may be lowered.

  When the fabric (raw material fabric) is a woven fabric, the yarn density (the density of warp and weft) of the fabric is, for example, 80 to 200/50 mm, preferably 100 to 180/50 mm, and more preferably 120 to 160/50 mm. Degree. If the density is too high, the amount of the binder containing the graphenes decreases, and the effects of the graphenes may be reduced. On the other hand, if the density is too low, the wear resistance is insufficient and the running life of the belt is reduced, and the adhesion amount of the binder is relatively increased.

  In order to improve the adhesiveness with the rubber component, the fabric has a resorcin-formalin-latex treatment liquid (RFL treatment liquid), an isocyanate compound (hexamethylene diisocyanate, tolylene diisocyanate, polymethylene polyphenyl polyisocyanate (polymeric MDI), etc.) Various adhesion treatments with an epoxy compound (such as bisphenol A type epoxy resin) may be performed (the fiber surface may be coated with these treatment agents).

(Friction coefficient reducing agent other than graphenes)
The reinforcing cloth may further contain a conventional friction coefficient reducing agent as a friction coefficient reducing agent (second friction coefficient reducing agent) other than graphenes. By combining the second friction coefficient reducing agent with graphenes, the friction coefficient can be reduced and the economy can be improved even if the amount of graphenes is small.

  Examples of the second friction coefficient reducing agent include inorganic friction coefficient reducing agents such as molybdenum disulfide, graphite, and carbon nanotubes; organic systems such as ultrahigh molecular weight polyethylene, fluororesin (polytetrafluoroethylene, and the like), phenol resin, and the like. Examples thereof include a friction coefficient reducing agent. These 2nd friction coefficient reducing agents can be used individually or in combination of 2 or more types.

  Of these second friction coefficient reducing agents, organic friction coefficient reducing agents such as ultrahigh molecular weight polyethylene and fluororesin are preferred.

  The shape of the second friction coefficient reducing agent is preferably granular (powder or indefinite shape) from the viewpoint of being easily dispersed uniformly in the fabric. Like the graphenes, the average particle size of the second friction coefficient reducing agent preferably has an average particle size smaller than the fiber size of the fibers constituting the fabric from the viewpoint of being easily dispersed uniformly in the fabric. For example, it may be 50 μm or less, and can be selected from the same range as the average particle diameter of the graphenes.

  The ratio of the second friction coefficient reducing agent may be such that the total amount with the graphenes is 100 parts by mass or less with respect to 100 parts by mass of the binder, for example, 1 to 50 parts by mass, preferably 5 to 40 parts by mass, and more preferably. Is about 10 to 30 parts by mass. The ratio of the second friction coefficient reducing agent may be 1 part by mass or more with respect to 1 part by mass of graphene, for example, 1 to 100 parts by mass, preferably 3 to 50 parts by mass, and more preferably 5 to 30 parts. It is about a mass part (especially 10-20 mass parts). If the ratio of the second friction coefficient reducing agent is too large, durability, adhesiveness, and workability may be reduced. Therefore, in applications where a high degree of adhesion is required, the ratio of the second friction coefficient reducing agent is preferably small, and may be 20 parts by mass or less with respect to 1 part by mass of graphene, for example, 15 masses. Or less, more preferably 10 parts by mass or less (particularly 1 part by mass or less), and the second friction coefficient reducing agent may not be included.

(Other additives)
In addition to the graphenes, the binder, and the fabric (if necessary, the second friction coefficient reducing agent), for example, when the binder is a rubber component, the reinforcing fabric is selected depending on the type of the rubber component. Agent or crosslinking agent [for example, sulfur-based vulcanizing agents (sulfur, sulfur chloride, etc.), oximes (quinone dioxime, etc.), guanidines (diphenylguanidine, etc.), organic peroxides (diacyl peroxide, peroxyester, Dialkyl peroxides, etc.), metal oxides (magnesium oxide, zinc oxide, etc.)], reinforcing agents (carbon black, silicon oxides such as hydrous silica), anti-aging agents (aromatic amine type anti-aging agents, benzimidazole type) An anti-aging agent, etc.). The ratio of the vulcanizing agent or the crosslinking agent is about 1 to 20 parts by mass (particularly 2 to 15 parts by mass) with respect to 100 parts by mass of the rubber component. The ratio of the reinforcing agent is about 20 to 100 parts by mass (particularly 30 to 80 parts by mass) with respect to 100 parts by mass of the rubber component. The proportion of the antioxidant is about 0.1 to 10 parts by mass (particularly 0.5 to 5 parts by mass) with respect to 100 parts by mass of the rubber component. The reinforcing cloth may further include an additive exemplified in the section of the belt main body described later.

(Structure of reinforcing cloth)
In the reinforcing fabric, it is sufficient that graphenes are fixed via a binder between the surface of the fabric and / or the fibers. From the viewpoint of durability, the graphenes and the binder are at least partially on the surface of the fabric. Are exposed, and the remainder is preferably uniformly present between the fibers in the fabric (impregnated or penetrated into the fabric). The reinforcing cloth containing the graphenes and the binder between the fibers in the cloth can further improve the slidability, and therefore the surface of the cloth impregnated with the graphenes and the binder (especially the outer surface serving as a transmission surface). In addition, a surface layer (thin sliding layer) containing graphenes and a binder may be included. The average thickness of the surface layer may be 500 μm or more, for example, about 100 to 1500 μm, preferably 300 to 1200 μm, and more preferably about 400 to 1000 μm (particularly 400 to 800 μm).

  The average thickness of the reinforcing cloth can be appropriately selected according to the type of the belt and the like, but is, for example, about 0.2 to 1.5 mm, preferably about 0.3 to 1 mm, and more preferably about 0.4 to 0.5 mm. Also good. If the thickness of the reinforcing cloth is too thin, the slidability may be reduced, and if it is too thick, the bending resistance of the belt may be reduced. In the present specification and claims, the average thickness of the reinforcing cloth can be measured based on a scanning electron microscope (SEM) photograph, and is determined as an average value at any five or more locations.

[Belt body]
Examples of the vulcanized rubber forming the belt main body (the rubber layer in the tension band of the resin block belt, and the compression layer and the extension layer in the V-ribbed belt and the low-edge V-belt) include the rubber components exemplified in the section of the reinforcing cloth. it can. The ratio of the rubber component to the entire belt body (or the total amount of the rubber composition) is, for example, 20% by mass or more (for example, 25 to 80% by mass), preferably 30% by mass or more (for example, 35 to 75% by mass), and more preferably 40%. It may be not less than mass% (especially 45 to 70 mass%).

  The belt main body (or the rubber composition forming the belt main body) may contain, as necessary, various additives and shorts in addition to the vulcanizing agent or the crosslinking agent exemplified in the section of the reinforcing cloth, the reinforcing agent, and the anti-aging agent. Fibers may be included.

  Additives (compounding agents) include known additives such as vulcanization aids, vulcanization accelerators, vulcanization retarders, metal oxides (eg, zinc oxide, magnesium oxide, calcium oxide, barium oxide, oxidation) Iron, copper oxide, titanium oxide, aluminum oxide, etc.), filler (clay, pyrophyllite (waxite clay), calcium carbonate, calcium phosphate, potassium titanate, aluminum borate, alumina, iron powder, mica, talc (water content) Magnesium silicate), ceramic particles, glass particles, etc.), plasticizers, softeners (paraffin oil, oils such as naphthenic oil), processing agents or processing aids (stearic acid, metal stearate, wax, paraffin) Etc.), adhesion improver [resorcin-formaldehyde co-condensate, hexamethoxymethyl melamine, etc. Melamine resins, co-condensates of these (resorcin-melamine-formaldehyde co-condensate, etc.), colorants, tackifiers, coupling agents (silane coupling agents, etc.), stabilizers (antioxidants, UV absorbers) And thermal stabilizers), lubricants, flame retardants, antistatic agents and the like. These additives can be used alone or in combination, and these additives can be selected according to the type, use, performance, etc. of the rubber.

  The proportion of the additive can be appropriately selected according to the type of rubber component. For example, the total ratio of the reinforcing agent, the metal oxide, and the filler is 10 parts by mass or more (for example, 20 to 150 parts by mass), preferably 20 parts by mass or more (for example, 25 to 120 parts by mass) with respect to 100 parts by mass of the rubber component. ), More preferably 30 parts by mass or more (for example, 35 to 100 parts by mass).

  Examples of the short fibers include cellulose fibers such as cotton and rayon, polyester fibers (PET fibers, etc.), polyamide fibers (aliphatic polyamide fibers such as polyamide 6, aramid fibers, etc.), and the like. The short fibers may be used alone or in combination of two or more.

  The average fiber length of the short fibers may be, for example, about 0.1 to 30 mm, preferably 0.2 to 20 mm, more preferably about 0.3 to 15 mm (particularly 0.5 to 5 mm).

  These short fibers may be surface-treated with a surfactant, a silane coupling agent, an epoxy compound, an isocyanate compound, or the like, if necessary.

  The ratio of the short fiber is, for example, about 0.5 to 50 parts by mass (for example, 1 to 40 parts by mass), preferably about 3 to 30 parts by mass (particularly 5 to 25 parts by mass) with respect to 100 parts by mass of the rubber component. May be.

[Tension band]
When the belt body is a tension band of a resin block belt, the tension band 2 is a rubber layer 5 in which cores 4 arranged at predetermined intervals in the belt width direction are embedded as a core as shown in FIGS. And a reinforcing cloth 6 that covers the upper and lower surfaces of the rubber layer 5. Further, as shown in FIGS. 1 and 2, the upper surface (outer peripheral surface) of the tension band 2 has a groove 21 a that can be engaged with the ridge 15 a of the block 10 in the belt (tension band) width direction. In the lower surface (inner peripheral surface) of the tension band 2, a groove 21 b that can be engaged with the ridge 15 b of the block 10 extends in the belt (tension band) width direction.

  The tension band is not limited to the tension band having the shape shown in FIGS. 1-2 and 4 as long as it can be integrated with the block by fitting, and a conventional tension band (center belt) can be used according to the shape of the block. ) Can be used. Furthermore, the number of tension bands is not limited to two, and may be one or three or more. However, the number of tension bands is usually two in terms of belt durability and running stability.

  The core 4 as the core body is disposed so as to extend in the longitudinal direction of the belt, and is generally disposed so as to extend in parallel at a predetermined pitch in parallel with the longitudinal direction of the belt. As the core wire, for example, a synthetic fiber such as a polyester fiber (polyalkylene arylate fiber), a polyamide fiber (such as an aramid fiber); Twist, Lang twist, etc.), steel wire, etc. are used. The average wire diameter (fiber diameter of the twisted cord) of the core wire may be, for example, about 0.5 to 3 mm, preferably about 0.6 to 2 mm, and more preferably about 0.7 to 1.5 mm. In the resin block belt, instead of the core wire, a woven fabric or a knitted fabric made of fibers forming the cord twist cord, or a metal thin plate may be embedded as a core. In order to improve the adhesiveness with the rubber component, the core wire is subjected to various adhesion treatments using a resorcin-formalin-latex treatment solution (RFL treatment solution), an isocyanate compound, an epoxy compound, and the like, similar to the cloth of the reinforcing cloth. You may give it.

[block]
In the case of a resin block belt, a conventional block can be used as the block. The block is not particularly limited as long as it can be fitted and integrated with a tension band (center belt), but a block having a substantially H-shaped plate surface is preferable from the viewpoint that two tension bands can be stably fixed. . In the substantially H-shaped block, the shape of the fitting groove for accommodating and fixing the tension band is not particularly limited as long as the tension band can be fixed by fitting. For example, on the opposing surface in the vertical direction of the fitting groove Although the shape which has the protruding item | line or the ditch | groove extended in a belt width direction is mentioned, Usually, it is a shape which has a protruding item | line. Further, the shape of the ridge is not particularly limited as long as it can be integrated with the tension band.

  The size of the block can be appropriately selected according to the type and size, and is not particularly limited, but the length in the belt thickness direction is about 10 to 17 mm, the length in the belt width direction is about 20 to 30 mm, and the width in the belt longitudinal direction is It is about 2-5 mm. The belt angle (side surface inclination angle) is, for example, about 24 to 30 °. The pitch of the block in the resin block belt integrated with the tension band can be appropriately selected according to the type and size of the belt, and is not particularly limited, but is, for example, about 1 to 6 mm, preferably about 2 to 4 mm. Adjacent blocks need only be separated and may be arranged without any gaps, but are usually arranged with an interval of about 0.01 to 0.1 mm, preferably about 0.02 to 0.08 mm. Yes.

  The block is usually formed of a resin composition including a resin component and carbon fiber, and may include an insert material formed of a hard material such as duralumin material. The resin component is usually a thermosetting resin such as a phenol resin.

[Production method of transmission belt]
The method for producing the transmission belt of the present invention is not particularly limited as long as the graphenes can be fixed with a binder in the reinforcing cloth.For example, in order to improve the adhesion between the cloth for forming the reinforcing cloth and the binder, A method of adding a binder (binder precursor) to a fabric containing graphenes after preliminarily containing graphenes in a treatment solution (such as an RFL treatment solution) for treating the fabric with an adhesive may be used. However, from the viewpoint that the dispersibility of graphenes in the binder can be improved, a method of undergoing a reinforcing cloth precursor forming step of fixing the graphenes to the cloth via the binder precursor to form the reinforcing cloth precursor is preferable.

  The reinforcing fabric precursor forming step is a method of impregnating a fabric with a liquid composition containing graphenes and a binder precursor (a composition in which graphenes are dispersed) and then drying (a method using a liquid composition). A method of integrating a solid composition containing graphenes and a binder precursor (a composition in which graphenes are kneaded and dispersed in a binder) with a fabric (a method using a solid composition) ).

  Examples of the method of impregnating the fabric with the liquid composition include a soaking method in which the fabric is immersed in the liquid composition, a spreading method in which the liquid composition is rubbed into the fabric, and a surface coating in which the liquid rubber composition is applied to the surface of the fabric. The method etc. are mentioned.

  In the soaking method, for example, after passing the fabric through a dipping tank containing a dilute liquid composition (such as rubber paste), the excess liquid composition is removed by passing between two rolls, The liquid composition may penetrate into the fabric. The impregnation treatment may be performed once for each of the front surface and the back surface. In the soaking method, a reinforcing cloth precursor and a reinforcing cloth in which a binder containing graphenes exists uniformly in the cloth (between fibers) can be obtained.

  In the spreading method, by using a coater such as a roll coater, a liquid composition (rubber paste) having a higher concentration than the liquid composition used in the soaking method is rubbed from the surface of the fabric, so that the liquid composition is contained inside the fabric. Infiltrate until. In the spreading method, a reinforcing cloth precursor and a reinforcing cloth in which a binder containing graphenes exists uniformly in the vicinity of the surface (between fibers) of the cloth can be obtained.

  In the surface coating method, for example, after applying the liquid composition to one side of the fabric, drying may be performed to remove the solvent, and at least part of the liquid composition may penetrate into the surface side region of the fabric. In the surface coating method, a coating film formed of a binder containing graphenes is formed on one side of the fabric without pressure bonding, and a reinforcing fabric precursor and a reinforcing fabric in which a part of the coating film is impregnated on the surface of the fabric are obtained. .

  The drying temperature of the reinforcing cloth precursor obtained by the impregnation treatment can be selected according to the type of the solvent, and is, for example, about 60 to 100 ° C. (particularly 70 to 90 ° C.).

  These methods may be combined. For example, the fabric may be impregnated with a liquid composition by a soaking method, and then the liquid composition may be further impregnated with a spreading method. In this case, the soaking method may use a liquid composition not containing graphenes, and the spreading method may use a liquid composition containing graphenes.

  In the method using a liquid composition, the liquid composition may contain a solvent. Examples of the solvent include hydrocarbons (for example, aromatic hydrocarbons such as toluene and xylene), halogenated hydrocarbons (for example, haloalkanes such as methylene chloride and chloroform), alcohols, etc., depending on the type of binder. (Alkanols such as ethanol, propanol, and isopropanol), ethers (eg, cyclic ethers such as dioxane and tetrahydrofuran), esters (eg, ethyl acetate, etc.), ketones (eg, acetone, methyl ethyl ketone, etc.) Examples thereof include cyclic ketones such as ketone and cyclohexanone), cellosolves, carbitols and the like. The solvent may be used alone or as a mixed solvent.

  The proportion of the solvent can be selected according to the impregnation method. In the soaking method, for example, 0.5 to 50 parts by mass, preferably 1 to 20 parts by mass, and more preferably about 5 to 15 parts by mass with respect to 1 part by mass of the binder. It is. In the spreading method and the surface coating method, the ratio of the solvent is, for example, 0.1 to 20 parts by mass, preferably 1 to 10 parts by mass, and more preferably about 3 to 8 parts by mass with respect to 1 part by mass of the binder. .

  Examples of the method using the solid composition include a frictioning method (friction) in which the solid composition is rubbed into the cloth, and a method of laminating and attaching the sheet-like composition and the cloth (of the sheet-like composition). Deposition method) and the like.

  In the frictioning method, for example, by using a calender roll, a solid composition (such as an unvulcanized rubber composition) and a fabric are simultaneously passed between rolls having different rotation speeds and pressed (squeezed), thereby causing the fabric to The solid composition may be rubbed in between the fibers. The shape of the solid composition is not particularly limited, but may be a sheet from the viewpoint that it can be printed uniformly on the fabric. The number of times of friction processing may be performed once for each of the front surface and the back surface. In the frictioning method, a reinforcing cloth precursor and a reinforcing cloth in which a binder containing graphenes is uniformly present inside the cloth (between fibers) can be obtained.

  In the method for depositing a sheet-like composition, for example, a sheet-like composition (such as a sheet-like unvulcanized rubber composition having a predetermined thickness) and a fabric are laminated between rolls that rotate at the same rotational speed. The sheet-like composition is attached to the fabric and integrated by bonding the two at the interface. In the method for depositing a sheet-like composition, a reinforcing cloth precursor and a reinforcing cloth in which a sheet-like composition formed with a binder containing graphenes on one side of the fabric is obtained. A part of the sheet-like composition may be impregnated in a region including the surface of the fabric, but usually the entire fabric is not uniformly impregnated.

  Among these methods, a soaking method, a spreading method, and a frictioning method that can uniformly distribute (or disperse) graphenes between fibers in the fabric are preferable.

  In addition, in order to improve the adhesiveness with a binder (especially rubber component), the cloth used for the reinforcing cloth precursor forming step is preliminarily immersed in a resorcin-formalin-latex treatment liquid (RFL treatment liquid). You may perform the process to dry, after processing to heat and / or being immersed in rubber paste. Furthermore, you may perform the process dried after immersing in the process liquid containing an epoxy compound or an isocyanate compound with respect to a fabric before these processes.

  When the binder precursor is unvulcanized rubber, the obtained reinforcing fabric precursor is subjected to a vulcanization process. In the vulcanization step, it is sufficient that the belt body and the reinforcing cloth are firmly integrated by covering and vulcanizing at least a part of the surface of the belt body precursor with the reinforcing cloth precursor. It can be carried out. The vulcanization temperature can be selected according to the type of rubber component, and is, for example, about 120 to 200 ° C, preferably about 150 to 180 ° C.

[Production method of resin block belt]
As a method for manufacturing the belt main body precursor, a conventional method can be used depending on the type of the belt. For example, in the case of a resin block belt, the belt main body precursor may be manufactured by the following method.

(Block manufacturing process)
The block can be produced by a conventional method. For example, the block can be produced by preparing the resin composition and then molding the obtained resin composition.

  As a method for preparing the resin composition, for example, a resin component and carbon fiber (and other additives as necessary) are put into a resin kneader such as a biaxial kneader and kneaded, and the recovered kneaded material is pulverized. And powdering or granulating.

  As a method for molding a resin composition, for example, the resin for forming a resin coating layer in a cavity after an insert material (metal reinforcing material) is placed in a mold cavity of a block molding machine and clamped Examples thereof include a method of forming a block by supplying a composition. In addition, when not using insert material for a block, the method of supplying a resin composition, etc., without arrange | positioning insert material in the cavity of a metal mold | die etc. are mentioned.

(Manufacturing process of tension band)
The tension band can also be produced by a conventional method. For example, after preparing a sheet-like uncrosslinked rubber composition, a core wire precursor, and a reinforcing cloth precursor, they can be molded using these materials.

  As a method for preparing a sheet-like uncrosslinked rubber composition, for example, after kneading raw rubber into a rubber kneading machine such as a Banbury mixer, the kneaded raw rubber compounding agent is added and kneaded, and further kneaded. And a method of processing the uncrosslinked rubber composition into a sheet shape by a calender roll.

  As a method for preparing the core wire precursor, for example, a process of heating a yarn or braid after being immersed in a resorcin-formalin-latex processing solution (RFL processing solution) and / or a processing of drying after being immersed in a rubber paste And the like. Furthermore, you may perform the process dried after being immersed in the process liquid containing an epoxy compound or an isocyanate compound with respect to a twisted thread or a braid before these processes.

  As a method for forming a tension band using these precursors, for example, the following method may be used. That is, first, a lower reinforcing cloth precursor formed in a cylindrical shape with a cylindrical mold provided with convex grooves extending in the axial direction of the concave groove shape on the inner peripheral surface of the tension band in the circumferential direction. A predetermined layer of an uncrosslinked rubber composition which is coated and processed into a sheet shape is provided thereon.

  Next, a cylindrical mold is placed in the heating and pressurizing apparatus, and the inside of the apparatus is set to a predetermined temperature and pressure so that the crosslinking of the uncrosslinked rubber composition proceeds about half, and the state is maintained for a predetermined time. At this time, the crosslinking of the uncrosslinked rubber composition proceeds about half and the shape of the lower half of the rubber layer is formed, and the uncrosslinked rubber composition flows and the ridges provided on the cylindrical mold are lowered. The side reinforcing cloth is pressed to form a concave groove.

  Subsequently, the cylindrical mold is taken out from the heating and pressurizing apparatus, the core wire precursor is spirally wound at an equal pitch from the semi-crosslinked rubber composition, and the uncrosslinked rubber is processed into a sheet shape again thereon. A predetermined layer of the composition is provided, and an upper reinforcing cloth precursor formed in a cylindrical shape is placed thereon.

  Next, an outer mold in which convex grooves extending in the axial direction of the groove-shaped mold on the outer peripheral surface of the tension band are provided at an equal pitch in the circumferential direction is set.

  Then, a cylindrical mold in which each precursor is set is placed in the heating and pressing apparatus, the interior of the apparatus is set to a predetermined temperature and pressure, and the state is maintained for a predetermined time. At this time, the crosslinking of the semi-crosslinked and uncrosslinked rubber composition proceeds to form a rubber layer. In addition, the adhesive on the surface of the core wire and the rubber layer are interdiffused, so that the core wire is integrally bonded to the rubber layer, and the adhesive and the rubber layer attached to the upper and lower reinforcing fabrics are interdiffused. By doing so, the upper and lower reinforcing fabrics are integrally bonded to the rubber layer. As described above, a cylindrical slab is molded on the surface of the cylindrical mold.

  Finally, the cylindrical mold is taken out from the heating and pressurizing device, the cylindrical slab formed on the peripheral surface is removed from the mold, this is cut into a band with a predetermined width, and a tension band is formed by chamfering or the like. Get.

(Transmission belt manufacturing process)
The protrusion of the fitting groove of the block is made to correspond to the concave groove of the tension band, the tension band is inserted into one fitting groove of the obtained block, and the block is fitted to the tension band. This operation is performed for the entire circumference of the tension band. In the same manner, a transmission belt is obtained by inserting a tension band into the other fitting groove of the block.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

Examples 1-4 and Comparative Examples 1-3
[Measurement of coefficient of friction and wear of reinforcing fabric]
Flat woven fabric [warp yarn (66 nylon made by Asahi Kasei Co., Ltd.), weft fabric (66 nylon (Woolley processing) made by Toray Industries, Inc.) 2/2 twill weave, fiber diameter 25 μm, warp density 150/50 mm , A weft density of 125 yarns / 50 mm], 1 mm thick spacers are placed on both ends, and the spreading rubber pastes of Formulations A to F shown in Table 1 are hung on the woven fabric, and the round bar is rolled to extend uniformly. After drying to some extent at room temperature, the reinforcing fabric precursor (weight per unit area 250 g / m ² ) spread by drying at 90 ° C. for 6 minutes was press vulcanized at 153 ° C. for 30 minutes to prepare a sheet-like test piece. . The test piece attached to the lower base is pressed against the mating material (width 10mm, length 20mm) attached to the upper part with a constant surface pressure, and the mating material attached to the upper part is reciprocated at a constant speed. The test was carried out under the conditions of a type friction wear tester (manufactured by Yonekura Seisakusho Co., Ltd.) under conditions of a speed of 10 m / min, a surface pressure of 0.5 MPa, a temperature of 70 ° C., and a running time of 20 hours. The material of the mating material was the same as the block resin composition shown in Table 2. For the friction coefficient, the load cell voltage was sampled every 10 seconds, and an average value for a test time of 20 hours was calculated. As the amount of wear, the weight reduction amount of the test piece before and after the test was measured. The results are shown in Table 6.

  In addition, the detail of the raw material in Table 1 is shown below.

HNBR (hydrogenated nitrile rubber): “Zetpol (registered trademark) 2010L” manufactured by Nippon Zeon Co., Ltd.
Carbon black: “Seast 116” manufactured by Tokai Carbon Co., Ltd.
Silica: “Toxeal 225G” manufactured by Oriental Silicon Corporation, BET specific surface area of 176 m ² / g
Anti-aging agent: “Nonflex DBD” manufactured by Seiko Chemical Co., Ltd.
Cross-linking agent: NOF Corporation "Perbutyl P-40"
Graphene: “GNH-X1” manufactured by Graphene Platform Co., Ltd.
UHMW-PE (ultra high molecular weight polyethylene): “GUR-4150” manufactured by Ticona Engineering Polymers
PTFE (polytetrafluoroethylene): “KTL-8F” manufactured by Kitamura Co., Ltd.

[Block molding]
Each component was charged into a biaxial resin kneader with the composition shown in Table 2 and kneaded, and the recovered kneaded material was pulverized into a powder or granule to obtain a block resin composition.

  In addition, the detail of the raw material in Table 2 is shown below.

Novolac phenol resin: “PSK-2320” manufactured by Gunei Chemical Industry Co., Ltd.
PAN-based carbon fiber: “HM35” manufactured by Toho Tenax Co., Ltd., average fiber length 6 mm
Pitch-based carbon fiber: “K223QE” manufactured by Mitsubishi Plastics Co., Ltd., average fiber length 6 mm
Aramid short fiber: “Technola” manufactured by Teijin Limited, average fiber length of 1 mm.

  A 2024P T361 duralumin was used as an insert material (reinforcing material) for the block, and a block in which the insert material was coated with the resin composition by a conventional method was prepared. The length of the block in the belt thickness direction was 13 mm, the length of the block in the belt longitudinal direction was 2.95 mm, and the belt angle was 26 °.

[Tensile band forming]
Each component was charged into a Banbury mixer with the composition shown in Table 3 and kneaded, and the recovered kneaded material was passed through an open roll to obtain a rubber layer composition having a predetermined tension band.

  In addition, the detail of the raw material in Table 3 is shown below.

HNBR: Nippon Zeon Co., Ltd .: “Zetpol 2010L”
HNBR alloy (hydrogenated nitrile rubber compounded with zinc dimethacrylate): “Zeoforte (registered trademark) ZSC2295CX” manufactured by Nippon Zeon Co., Ltd.
Polyamide short fiber: “6,6-nylon” manufactured by Asahi Kasei Corporation, average fiber length 6 mm
Aramid short fiber: “Technola” manufactured by Teijin Limited, average fiber diameter of 12 μm, average fiber length of 3 mm
Silica: “Toxeal 225G” manufactured by Oriental Silicas Corporation
Anti-aging agent 1: “Nonflex DBD” manufactured by Seiko Chemical Co., Ltd.
Anti-aging agent 2: “NOCRACK MB” manufactured by Ouchi Shinsei Chemical Co., Ltd.
Anti-aging agent 3: “Nonflex RD” manufactured by Seiko Chemical Co., Ltd.
Crosslinking agent: “Perbutyl P-40” manufactured by NOF Corporation.

  Using the tension band rubber layer composition, the core wire precursor, and the reinforcing cloth precursor, a tension band was prepared by the conventional method described above.

  In addition, a twisted cord of an aramid fiber having a diameter of 0.72 mm subjected to a heating process after being immersed in an RFL aqueous solution and a drying process after being immersed in rubber paste was used for the core wire.

  On the other hand, each of the upper and lower reinforcing fabrics was immersed in the polyamide fiber woven fabric used in the measurement of the friction coefficient and the wear amount of the reinforcing fabric for 1 minute in the soaking rubber paste shown in Table 4, and then taken out. Dry at 80 ° C. for 3 minutes. Furthermore, the woven fabric after soaking is the same method as the reinforcing fabric precursor prepared by measuring the friction coefficient and the wear amount of the reinforcing fabric using the rubber paste for the blending A to F shown in Table 1. A reinforcing cloth precursor having a thickness of 0.8 mm was obtained. From the weight change and the charging ratio, the ratio of graphene to the fabric was determined.

  In addition, the detail of the raw material in Table 4 is shown below.

HNBR: “Zetpol 2010L” manufactured by Nippon Zeon Co., Ltd.
HNBR Alloy: “Zeoforte ZSC2295CX” manufactured by Nippon Zeon Co., Ltd.
Silica: “Toxeal 225G” manufactured by Oriental Silicas Corporation
Anti-aging agent 1: “Nonflex DBD” manufactured by Seiko Chemical Co., Ltd.
Anti-aging agent 2: “NOCRACK MB” manufactured by Ouchi Shinsei Chemical Co., Ltd.
Anti-aging agent 3: “Nonflex RD” manufactured by Seiko Chemical Co., Ltd.
Crosslinking agent: “Perbutyl P-40” manufactured by NOF Corporation.

[Molding of resin block belt]
The block was incorporated into the tension band to produce a resin block belt having the same configuration as the resin block belt shown in FIGS. The resin block belt has a belt circumferential length on the core wire pitch line of 612 mm, a belt width on the core wire pitch line of 25 mm, a length of the block in the belt thickness direction of 13 mm, and a length of the block in the longitudinal direction of the belt of 2. The block pitch was 95 mm and the block pitch was 3 mm.

[Belt durability test]
In the belt durability running test, each of the resin block belts of the example and the comparative example was wound around the driving pulley and the driven pulley, and the driving pulley was rotated in an atmosphere of 70 ° C. The angle of the V groove of the driving pulley and the driven pulley was 26 °, and the winding diameter of the resin block belt around each pulley was a value shown in Table 5. The load was set to the value shown in Table 5, and the rotation speed was set to 5000 rpm when there was no load. The axial load was such that the transmission belt did not slip with respect to the load, and the values shown in Table 5 were used. The distance between the shafts of both pulleys was not fixed so that the shaft load was constant during the traveling of the transmission belt. The belt tension in the stationary state is about half of the axial load. In the belt durability running test, the durability of the belt was evaluated after running for 400 hours, and the amount of noise during running was measured by the following method. The measurement results are shown in Table 6 together with the results of the wear test of each reinforcing fabric.

(Noise while driving)
Using a noise meter ("LA-4440" manufactured by Ono Sokki Co., Ltd.) at a position between the driving pulley and the driven pulley, 150 mm in front of the end surface of the belt, the A characteristic was measured.

  As is clear from the results in Table 6, Comparative Example 1 not containing a friction coefficient reducing agent had a high friction coefficient, a large amount of wear, a large noise in the running test, and rubber cracking and cutting failure were reached in 238 hours.

  In Comparative Example 2 containing ultra high molecular weight polyethylene, although a certain effect was seen in the reduction of the friction coefficient, the effect was low compared to the case where graphene was added. Further, in the running test, the noise was loud and the rubber cracked and the cutting failure was reached in 292 hours.

  In these two examples, since the friction coefficient is high, the heat generated when the resin block and the reinforcing cloth are rubbed is large, so that the rubber is hardened and deteriorated, and the wear of the reinforcing cloth and the resin block progresses, causing rattling. However, the noise is thought to have increased.

  Furthermore, in Comparative Example 3 containing a large amount of ultrahigh molecular weight polyethylene, although there was a relatively large friction coefficient reducing effect, the adhesive force was also greatly reduced. Due to the decrease in the adhesive force, peeling occurred between the rubber layer in the tension band and the reinforcing cloth in the running test, leading to failure in a short time.

  On the other hand, in Examples 1 to 4 to which graphene was added, the friction coefficient was greatly reduced, no failure occurred even after running for 400 hours, and the noise was low. In particular, as the amount of graphene increased as in Example 2, the effect was great, and the effect was also enhanced by using high molecular weight polyethylene or PTFE in combination. Since a large effect can be obtained by adding a small amount of 0.5 parts by mass, there is an advantage that an increase in material cost is minimized and there is little influence on physical properties, adhesiveness, and workability.

  The power transmission belt of the present invention includes various belts in which at least a part of the surface of the belt body is covered with a reinforcing cloth, such as a flat belt, a V belt, a V ribbed belt, a wrapped V belt, a low edge V belt, a low edge cogged V belt, It can be used as a friction transmission belt such as a resin block belt; a mesh transmission belt such as a toothed belt, etc., and has excellent wear resistance, so that it can be effectively used as a resin block belt used at high loads.

DESCRIPTION OF SYMBOLS 1 ... Resin block belt 2 ... Tension band 10 ... Block 11 ... Upper beam part 12 ... Lower beam part 13 ... Center pillar part 14 ... Fitting groove 15a, 15b ... Projection

Claims (13)

  A power transmission belt in which at least a part of a surface of a belt main body is coated with a reinforcing cloth including graphenes, a binder, and a cloth.   The power transmission belt according to claim 1, wherein the graphenes are fixed via a binder between the surface of the fabric and / or the fibers.   The transmission belt according to claim 1 or 2, wherein at least a part of the graphenes is exposed on the surface of the fabric, and the remaining graphenes are uniformly present between the fibers in the fabric.   The power transmission belt according to any one of claims 1 to 3, wherein the graphene has an average particle size of 0.1 to 3 µm.   The power transmission belt according to any one of claims 1 to 4, wherein the binder is vulcanized rubber.   The transmission belt according to any one of claims 1 to 5, wherein a proportion of the graphene is 0.5 to 10 parts by mass with respect to 100 parts by mass of the binder.   The transmission belt according to any one of claims 1 to 6, wherein a ratio of the graphenes is 0.1 to 5 parts by mass with respect to 100 parts by mass of the fabric.   The power transmission belt according to any one of claims 1 to 7, wherein the reinforcing cloth further includes a friction coefficient reducing agent other than graphenes.   The power transmission belt according to any one of claims 1 to 8, wherein the binder is the same vulcanized rubber as that of the belt main body.   A transmission belt comprising a tension band which is a belt body and a plurality of blocks which are arranged at substantially equal intervals in the length direction of the tension band and integrated with the tension band by fitting, The transmission belt according to any one of claims 1 to 9, wherein at least a contact portion of the block with the upper beam portion and the lower beam portion of the surface of the tension band is covered with a reinforcing cloth.   The manufacturing method of the transmission belt in any one of Claims 1-10 including the reinforcement cloth precursor formation process which fixes graphenes to a cloth via a binder precursor, and forms a reinforcement cloth precursor.   The manufacturing method of Claim 11 which dries after impregnating the liquid composition containing graphenes and a binder precursor in a reinforcement cloth precursor formation process.   The binder precursor is an unvulcanized rubber, and further includes a vulcanization step in which at least a part of the surface of the belt body precursor including the unvulcanized rubber is coated with a reinforcing cloth precursor and vulcanized. Manufacturing method.

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