JP6529323B2 - Toothed belt - Google Patents

Description

  The present disclosure relates to a toothed belt.

  The application of rubber compositions containing so-called cellulose nanofibers to transmission belts is known.

  For example, Patent Document 1 discloses that a rubber composition containing a cellulose fine fiber having a carboxy group with an average fiber diameter of 0.1 to 200 nm and subjected to hydrophobic modification treatment is applied to a transmission belt. .

  Patent Document 2 discloses that a rubber composition containing cellulose nanofibers is applied to the inner surface rubber layer of a flat belt.

JP, 2014-125607, A JP, 2015-31315, A

  An object of the present disclosure is to improve the durability of a toothed belt.

  The toothed belt of the present disclosure is a tooth formed of a rubber composition having a flat belt-like base and a plurality of teeth integrally provided on the surface on one side of the base at intervals in the belt length direction. A toothed belt comprising: an attaching belt main body; and a tooth side reinforcing cloth attached to the toothed belt main body so as to cover the tooth side surface with an adhesive layer containing a rubber component. At least one of the rubber composition forming the base, the rubber composition forming the teeth, and the adhesive layer has a fiber diameter distribution range of 50 to 500 nm.

  According to the toothed belt of the present disclosure, at least one of the rubber composition forming the base, the rubber composition forming the teeth, and the adhesive layer has a cellulose-based fineness including a fiber diameter distribution range of 50 to 500 nm. By containing the fiber, high durability can be obtained.

FIG. 1 is a perspective view schematically showing an exemplary toothed belt according to a first embodiment. FIG. 2 is a partial cross-sectional view of a belt mold used for manufacturing the toothed belt according to the first embodiment. FIG. 3: is 1st explanatory drawing of the manufacturing method of the toothed belt which concerns on Embodiment 1. FIG. FIG. 4 is a second explanatory view of the method of manufacturing the toothed belt according to the first embodiment. FIG. 5 is a third explanatory view of the manufacturing method of the toothed belt according to the first embodiment. FIG. 6 is a first explanatory view of a method of manufacturing a toothed belt according to a second embodiment. FIG. 7 is a second explanatory view of the manufacturing method of the toothed belt according to the second embodiment. FIG. 8 is a third explanatory view of the manufacturing method of the toothed belt according to the second embodiment. FIG. 9 is a cross-sectional view showing the interface structure between the tooth portion side reinforcing cloth and the toothed belt main body in the fourth embodiment. FIG. 10 is a cross-sectional view showing the interface structure between the tooth portion side reinforcing cloth and the toothed belt main body in the fifth embodiment. FIG. 11 is a view showing a pulley layout in a belt running tester for evaluating the tooth chipping resistance and the wear resistance of a toothed belt.

  Hereinafter, embodiments will be described in detail based on the drawings.

Embodiment 1
(Toothed belt B)
FIG. 1 shows a toothed belt B according to a first embodiment.

  The toothed belt B according to the first embodiment includes an endless toothed belt main body 10 formed of a rubber composition. The toothed belt body 10 has a flat belt-like base portion 11a and a plurality of tooth portions 11b integrally provided at a constant pitch on one side, that is, on the surface on the inner peripheral side at intervals in the belt length direction. Have. A tooth portion side reinforcing cloth 12 is attached to the toothed belt main body 10 so as to cover the tooth portion side surface. Further, on the inner peripheral side of the base 11 a in the toothed belt main body 10, the core wire 13 is embedded so as to form a spiral having a pitch in the belt width direction. The toothed belt B according to the first embodiment is suitably used, for example, as a power transmission member of a belt transmission in a machine tool or the like, particularly in a machine tool whose operation time is about 3 to 120 hours a year. The toothed belt B according to the first embodiment has, for example, a belt length of 500 to 3000 mm, a belt width of 10 to 200 mm, and a belt thickness of 3 to 20 mm. Moreover, the teeth 11 b have a width of 0.63 to 16.46 mm, a height of 0.37 to 9.6 mm, and a pitch of 1.0 to 31.75 mm, for example.

  The teeth 11b of the toothed belt main body 10 may be trapezoidal teeth having a trapezoidal shape in a side view, may be semicircular, and may have other shapes. Good. The teeth 11b may be formed so as to extend in the belt width direction or may be helical teeth formed so as to extend in a direction inclined with respect to the belt width direction.

  In the toothed belt main body 10, an uncrosslinked rubber composition prepared by mixing and kneading various rubber compounding agents in a rubber component in addition to cellulose fine fibers including a fiber diameter distribution range of 50 to 500 nm is heated and added. It is formed of a rubber composition which is pressed and crosslinked by a crosslinking agent. Thus, the durability of the toothed belt B can be improved by the rubber composition forming the toothed belt main body 10 containing cellulosic fine fibers including a distribution range of fiber diameter of 50 to 500 nm. . Here, the "fine fibers" in the present application mean fibers having a fiber diameter of 1.0 μm or less.

  Examples of the rubber component of the rubber composition forming the toothed belt main body 10 include hydrogenated acrylonitrile rubber (H-NBR), hydrogenated acrylonitrile rubber reinforced with unsaturated carboxylic acid metal salt (H-NBR), ethylene・ Propylene copolymer (EPR), ethylene / propylene / diene terpolymer (EPDM), ethylene / octene copolymer, ethylene-α-olefin elastomer such as ethylene / butene copolymer, chloroprene rubber (CR), and chlorosulfonated polyethylene rubber (CSM Etc.). The rubber component of the rubber composition forming the toothed belt main body 10 is preferably one or two or more of these blended rubbers.

  In the case of H-NBR reinforced with metal salts of unsaturated carboxylic acids, examples of unsaturated carboxylic acids include methacrylic acid and acrylic acid, and as metals, for example, zinc, calcium, magnesium, aluminum, etc. Can be mentioned.

  The cellulose-based fine fiber is a fiber material derived from the cellulose fine fiber composed of a skeletal component of a plant cell wall obtained by finely loosening a plant fiber. Examples of raw material plants of the cellulose fine fiber include trees, bamboo, rice (rice straw), potato, sugar cane (bagasse), aquatic plants, seaweed and the like. Of these, wood is preferred.

  The cellulose fine fiber may be either cellulose fine fiber itself or hydrophobicized hydrophobized cellulose fine fiber. In addition, as the cellulose fine fiber, the cellulose fine fiber itself and the hydrophobized cellulose fine fiber may be used in combination. From the viewpoint of dispersibility, it is preferable that the cellulose fine fiber contains a hydrophobized cellulose fine fiber. The hydrophobized cellulose fine fibers include cellulose fine fibers in which part or all of hydroxyl groups of cellulose are substituted by hydrophobic groups, and cellulose fine fibers subjected to hydrophobized surface treatment with a surface treatment agent.

  As a hydrophobization for obtaining the cellulose fine fiber in which some or all of the hydroxyl groups of cellulose were substituted by the hydrophobic group, for example, esterification (acylation) (alkyl esterification, complex esterification, β-keto esterification, etc. And alkylation, tosylation, epoxidation, arylation and the like. Of these, esterification is preferred. Specifically, in the esterified hydrophobized cellulose fine fiber, part or all of the hydroxyl groups of the cellulose are carboxylic acids such as acetic acid, acetic anhydride, propionic acid and butyric acid, or halides thereof (especially chlorides) Cellulose microfibers acylated by As a surface treatment agent for obtaining the cellulose fine fiber by which surface treatment agent hydrophobized surface treatment, a silane coupling agent etc. are mentioned, for example.

  From the viewpoint of improving the durability of the toothed belt B, the cellulose fine fiber preferably has a wide fiber diameter distribution, and the fiber diameter distribution range includes 50 to 500 nm. The lower limit of the fiber diameter distribution is preferably 20 nm or less, more preferably 10 nm or less from that point of view. The upper limit is preferably 700 nm or more, more preferably 1 μm or more, from the same viewpoint. It is preferable to include 20 nm-700 mm, and, as for the distribution range of the fiber diameter of a cellulose type | system | group fine fiber, it is more preferable to include 10 nm-1 micrometer.

  The average fiber diameter of the cellulose fine fiber contained in the rubber composition forming the toothed belt main body 10 is preferably 10 nm or more, more preferably 20 nm or more, and preferably 700 nm or less, more preferably 100 nm or less It is.

  The distribution of the fiber diameter of the cellulose-based fine fiber is obtained by freeze-pulverizing a sample of the rubber composition forming the toothed belt main body 10 and then observing the cross section with a transmission electron microscope (TEM) and 50 cellulose-based A fine fiber is selected arbitrarily, a fiber diameter is measured, and it calculates | requires based on the measurement result. Further, the average fiber diameter of the cellulose-based fine fibers is determined as the number average of the fiber diameters of the 50 arbitrarily selected cellulose-based fine fibers.

  The cellulose-based fine fibers may be either of high aspect ratio produced by mechanical disintegration means, or needle-like crystals produced by chemical disintegration means. Among these, those manufactured by mechanical disintegration means are preferable. In addition, as the cellulose-based fine fiber, one produced by mechanical disintegration means and one produced by chemical disintegration means may be used in combination. Examples of the disintegration device used for the mechanical disintegration means include a kneader such as a twin-screw kneader, a high pressure homogenizer, a grinder, a bead mill and the like. As a process used for a chemical disintegration means, an acid hydrolysis process etc. are mentioned, for example.

  From the viewpoint of improving the durability of the toothed belt B, the content of the cellulose fine fiber in the rubber composition forming the toothed belt main body 10 is preferably 1 part by mass or more with respect to 100 parts by mass of the rubber component, More preferably, it is 3 parts by mass or more, more preferably 5 parts by mass or more, preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 10 parts by mass or less.

  Examples of the rubber compounding agent include a reinforcing material, a processing aid, a vulcanization acceleration aid, a plasticizer, a co-crosslinking agent, a crosslinking agent, a vulcanization accelerator, an antiaging agent and the like.

  As a reinforcing material, for carbon black, for example, channel black; furnace black such as SAF, ISAF, N-339, HAF, N-351, MAF, FEF, SRF, GPF, ECF, N-234, etc .; FT, MT, etc. Thermal black; acetylene black and the like. The reinforcing material also includes silica. The reinforcing material is preferably one or more of these. The content of the reinforcing material is, for example, 20 to 60 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition.

  Examples of processing aids include stearic acid, polyethylene wax, metal salts of fatty acids, and the like. The processing aid is preferably one or more of these. The content of the processing aid is, for example, 0.5 to 2 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition.

  Examples of the vulcanization acceleration auxiliary include metal oxides such as zinc oxide (zinc white) and magnesium oxide, metal carbonates, fatty acids and derivatives thereof. It is preferable that 1 or 2 types or more of these are used as the vulcanization acceleration coagent. The content of the vulcanization acceleration auxiliary is, for example, 3 to 7 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition.

  Examples of the plasticizer include dialkyl phthalates such as dibutyl phthalate (DBP) and dioctyl phthalate (DOP), dialkyl adipates such as dioctyl adipate (DOA), and dialkyl sebacates such as dioctyl sebacate (DOS). The plasticizer is preferably one or more of these. The content of the plasticizer is, for example, 0.1 to 40 parts by mass with respect to 100 parts by mass of the rubber component.

  As a co-crosslinking agent, liquid rubbers, such as liquid NBR, etc. are mentioned, for example. The co-crosslinking agent is preferably one or more kinds. The content of the co-crosslinking agent is, for example, 3 to 7 parts by mass with respect to 100 parts by mass of the rubber component.

  Crosslinking agents include sulfur and organic peroxides. As a crosslinking agent, sulfur may be blended, an organic peroxide may be blended, and both of them may be used in combination. The blending amount of the crosslinking agent is, for example, 1 to 5 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition in the case of sulfur, and in the case of organic peroxide, with respect to 100 parts by mass of the rubber component of the rubber composition. For example, 1 to 5 parts by mass.

  As a vulcanization accelerator, for example, thiuram (eg TETD, TT, TRA etc.), thiazole (eg MBT, MBTS etc.), sulfenamide (eg CZ etc), dithiocarbamate (eg BZ-P) Etc.). The vulcanization accelerator is preferably one or more of these. The content of the vulcanization accelerator is, for example, 2 to 5 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition.

  Examples of the antiaging agent include amine-ketone antiaging agents, diamine antiaging agents, and phenolic antiaging agents. It is preferable that an antiaging agent is 1 type or 2 types or more among these. The content of the antiaging agent is, for example, 0.1 to 5 parts by mass with respect to 100 parts by mass of the rubber component.

  The rubber composition forming the toothed belt main body 10 may contain short fibers having a fiber diameter of 10 μm or more.

  The tooth side reinforcing cloth 12 is made of, for example, a cloth material such as a woven fabric, a knitted fabric or a non-woven fabric formed of yarns such as cotton, polyamide fiber, polyester fiber, aramid fiber and the like. The tooth side reinforcing cloth 12 preferably has extensibility. The thickness of the tooth portion side reinforcing cloth 12 is, for example, 0.3 to 2.0 mm. A bonding process for bonding with the toothed belt main body 10 is performed on the tooth side reinforcing cloth 12.

  The core wire 13 is made of a twisted yarn formed of glass fiber, aramid fiber, polyamide fiber, polyester fiber or the like. The diameter of the core wire 13 is, for example, 0.5 to 2.5 mm, and the dimension between mutually adjacent core wires in the cross section is, for example, 0.05 to 0.20 mm. The core wire 13 is subjected to an adhesion process for providing adhesion to the toothed belt body 10.

  According to the toothed belt B according to Embodiment 1 of the above configuration, the rubber composition forming the toothed belt main body 10 including the base 11a and the teeth 11b is a cellulose having a fiber diameter distribution range of 50 to 500 nm. By containing the system fine fiber, the excellent reinforcing effect can be obtained, and in particular, the chipping of the tooth portion 11b can be suppressed, and the excellent oil resistance can be obtained. As a result, high durability can be obtained. it can.

(Method of manufacturing toothed belt B)
The manufacturing method of the toothed belt B which concerns on Embodiment 1 is demonstrated based on FIGS.

  FIG. 2 shows a belt mold 20 used for manufacturing the toothed belt B according to the first embodiment.

  The belt forming die 20 is cylindrical, and on the outer peripheral surface thereof, tooth portion forming grooves 21 extending in the axial direction are formed at a constant pitch at intervals in the circumferential direction.

  The manufacturing method of the toothed belt according to the first embodiment includes a material preparation process, a forming process, a crosslinking process, and a finishing process.

<Material preparation process>
-Uncrosslinked rubber sheet 11 'for base and teeth
First, cellulose fine fibers are added to the masticated rubber component and dispersed by kneading.

  Here, as a method of dispersing the cellulose fine fiber in the rubber component, for example, a dispersion (gel) in which the cellulose fine fiber is dispersed in water is added to the rubber component masticated with an open roll, Method of vaporizing water while kneading them, Master of cellulose-based fine fiber / rubber obtained by vaporizing water by mixing dispersion (gel) in which cellulose fine fiber is dispersed in water and rubber latex A method of charging a batch into a masticated rubber component, a dispersion obtained by dispersing cellulose fine fibers in a solvent and a solution in which a rubber component is dissolved in a solvent are mixed to obtain a solvent. A method of charging a cellulose-based fine fiber / rubber master batch into a masticating rubber component, a dispersion (gel) in which cellulose-based fine fibers are dispersed in water is freeze-dried and pulverized. Things and how to put into a rubber component is masticated, methods and the like to introduce cellulosic microfibers made hydrophobic in rubber component is masticated.

  Next, while kneading the rubber component and the cellulose fine fiber, the various rubber compounding agents are added and the kneading is continued.

  Then, the obtained non-crosslinked rubber composition is formed into a sheet by calendar molding or the like to prepare a non-crosslinked rubber sheet 11 'for the base and the tooth portion.

-Tooth side reinforcement cloth 12 '-
A bonding process is performed on the tooth side reinforcing cloth 12 '. Specifically, the tooth-part-side reinforcing cloth 12 'is subjected to an RFL adhesion process of immersing and heating in an RFL aqueous solution. Moreover, the base adhesion | attachment process which is immersed and heated in a base | substrate adhesion process liquid before RFL adhesion process as needed is given. Also, if necessary, a soaking rubber paste adhesion process of immersing in rubber paste and drying after RFL adhesion processing, and / or a coating rubber paste of coating and drying a rubber paste on the surface to be the toothed belt main body 10 side Apply adhesion treatment.

  Next, both ends of the tooth portion side reinforcing cloth 12 'subjected to the bonding process are joined to form a tubular shape.

-Heart 13 '-
The bonding process is performed on the core wire 13 '. Specifically, the cord 13 'is subjected to an RFL adhesion treatment in which the core wire 13' is immersed and heated in an aqueous resorcin / formalin / latex solution (hereinafter referred to as "RFL aqueous solution"). In addition, if necessary, a base adhesion treatment of immersing and heating in a base adhesion treatment solution before RFL adhesion treatment and / or a rubber paste adhesion treatment of immersing in rubber paste and drying after RFL adhesion treatment is performed.

<Molding process>
As shown in FIG. 3, a cylindrical tooth portion side reinforcing cloth 12 'is covered on the outer periphery of the belt forming die 20, the core wire 13' is spirally wound from above, and the uncrosslinked rubber sheet 11 'is further wound thereon. Wrap At this time, a laminated molded body B ′ is formed on the belt mold 20. The uncrosslinked rubber sheet 11 'may be used so that the row direction corresponds to the belt length direction, or it may be used such that the row direction corresponds to the belt width direction. .

<Crosslinking step>
As shown in FIG. 4, after winding the release paper 22 around the outer periphery of the laminated molded body B ′, the rubber sleeve 23 is covered from above, and the rubber sleeve 23 is placed in the vulcanized can for sealing, and Is filled with high temperature and high pressure steam and held for a predetermined molding time. At this time, the non-crosslinked rubber sheet in the laminated molded body B 'flows while pressing the tooth portion side reinforcing cloth 12' and flows into the tooth portion forming groove 21 of the belt forming die 20, and the crosslinking progresses. And, the tooth part side reinforcing cloth 12 'and the core wire 13' are combined and integrated, and finally, as shown in FIG. 5, a cylindrical belt slab S is molded. The molding temperature of the belt slab S is, for example, 100 to 180 ° C., the molding pressure is, for example, 0.5 to 2.0 MPa, and the molding time is, for example, 10 to 60 minutes.

<Finish process>
Depressurize the inside of the vulcanizer to release the seal, take out the belt slab S molded between the belt mold 20 and the rubber sleeve 23 and remove it, and polish the back side to adjust the thickness After that, the toothed belt B is manufactured by sectioning into a predetermined width.

Second Embodiment
(Toothed belt B)
Since the toothed belt B according to the second embodiment has the same appearance as that of the first embodiment, the toothed belt B will be described below based on FIG.

  In the toothed belt B according to the second embodiment, the rubber composition forming the base 11 a of the toothed belt main body 10 contains cellulose-based fine fibers including a fiber diameter distribution range of 50 to 500 nm. On the other hand, the rubber composition forming the tooth portion 11b does not contain such cellulose fine fiber. In addition, the rubber composition which forms the tooth part 11b may contain the cellulose fine fiber whose distribution range of a fiber diameter does not contain 50-500 nm.

  The other configuration is the same as that of the first embodiment.

  According to the toothed belt B according to Embodiment 2 of the above configuration, the rubber composition forming the base portion 11a is excellent because the fiber diameter distribution range contains 50 to 500 nm of cellulose-based fine fibers. The reinforcing effect can be obtained, and excellent oil resistance can also be obtained, and as a result, high durability can be obtained.

(Method of manufacturing toothed belt B)
In the manufacturing method of toothed belt B concerning Embodiment 2, the uncrosslinked rubber sheet for the base containing the cellulose fine fiber containing 50-500 nm of distribution ranges of a fiber diameter similarly to Embodiment 1 in material preparation process. Make 11a '. In addition, uncrosslinked rubber containing no cellulose fine fiber including 50 to 500 nm of the fiber diameter distribution range obtained by blending various rubber compounding agents with the rubber component and kneading with a kneader such as a kneader or a Banbury mixer. A non-crosslinked rubber 11 b ′ for a tooth portion is formed by forming the composition into the shape of the tooth portion forming groove 21 of the belt molding die 20.

  Then, in the forming step, as shown in FIG. 6, after covering the outer periphery of the belt forming die 20 with the tubular tooth portion side reinforcing cloth 12 ′ and along the tooth portion forming groove 21, as shown in FIG. Insert the uncrosslinked rubber 11b 'for the tooth into each tooth forming groove 21 and spirally coil the core 13' from above as shown in FIG. 8, and further over the uncrosslinked for the base from above A laminated molded body B 'is formed by winding the rubber sheet 11a'. In the crosslinking step, crosslinking of the non-crosslinked rubber 11b 'for the tooth portion and the non-crosslinked rubber sheet 11a' for the base in the laminated molded body B 'proceeds, and further with the tooth side reinforcing cloth 12' and the core wire 13 '. Are integrally integrated, and finally, a cylindrical belt slab S similar to that shown in FIG. 5 in the first embodiment is formed.

  The other methods are the same as in the first embodiment.

Third Embodiment
(Toothed belt B)
Since the toothed belt B according to the third embodiment has the same appearance as that of the first embodiment, it will be described below based on FIG. 1.

  In the toothed belt B according to the third embodiment, the rubber composition forming the tooth portion 11 b in the toothed belt main body 10 contains cellulose-based fine fibers including a fiber diameter distribution range of 50 to 500 nm. On the other hand, the rubber composition forming the base 11a does not contain such cellulose-based fine fibers. In addition, the rubber composition which forms the base 11a may contain the cellulose fine fiber whose distribution range of a fiber diameter does not contain 50-500 nm.

  The other configuration is the same as that of the first embodiment.

  According to the toothed belt B according to Embodiment 3 of the above configuration, the rubber composition forming the tooth portion 11b contains cellulose fine fibers including the fiber diameter distribution range of 50 to 500 nm. An excellent reinforcing effect can be obtained, in particular, chipping of the teeth 11b can be suppressed, and excellent oil resistance can also be obtained, and as a result, high durability can be obtained.

(Method of manufacturing toothed belt B)
In the method of manufacturing the toothed belt B according to the third embodiment, in the material preparation step, as in the first embodiment, uncrosslinked rubber for a tooth portion containing cellulose fine fibers including a fiber diameter distribution range of 50 to 500 nm. The composition is kneaded, and a non-crosslinked rubber 11b 'for a tooth portion formed in the shape of the tooth portion forming groove 21 of the belt forming die 20 is produced. In addition, the uncrosslinked rubber composition not containing such cellulose-based fine fibers obtained by blending various rubber compounding agents with the rubber component and kneading with a kneader such as a kneader or a Banbury mixer is formed into a sheet by calendar molding etc. It shape | molds and produces non-crosslinked rubber sheet 11a 'for base parts.

  Then, in the forming step, similarly to the case shown in FIG. 6 in the second embodiment, after covering the outer periphery of the belt forming die 20 with the tubular tooth portion side reinforcing cloth 12 ′ and along the tooth portion forming groove 21, In the same manner as shown in FIG. 7, uncrosslinked rubber 11 b ′ for the tooth portion is inserted into each tooth portion forming groove 21, and in the same manner as shown in FIG. Further, a laminated molded body B 'is formed by winding an uncrosslinked rubber sheet 11a' for the base from above. In the crosslinking step, crosslinking of the non-crosslinked rubber 11b 'for the tooth portion and the non-crosslinked rubber sheet 11a' for the base in the laminated molded body B 'proceeds, and further with the tooth side reinforcing cloth 12' and the core wire 13 '. Are integrally integrated, and finally, a cylindrical belt slab S similar to that shown in FIG. 5 in the first embodiment is formed.

  The other methods are the same as in the first embodiment.

Fourth Embodiment
(Toothed belt B)
Since the toothed belt B according to the fourth embodiment has the same appearance as that of the first embodiment, the following description will be given based on FIG.

  In the toothed belt B according to the fourth embodiment, the tooth portion side reinforcing cloth 12 is subjected to an RFL bonding process of immersing and heating in an RFL aqueous solution. As a result, as shown in FIG. 9, the tooth side reinforcing cloth 12 is adhered to the toothed belt main body 10 through the RFL adhesive layer 14 formed by the RFL adhesion process. In addition, before RFL adhesion processing, the base adhesion processing which consists of the solution which made the base adhesion processing agent such as epoxy resin and isocyanate resin (block isocyanate) dissolve in the solvent such as toluene or disperse it in water. It is preferable that a base adhesion treatment of immersion in liquid and heating is performed, and a base adhesion layer is provided under the RFL adhesion layer 14. Also, after RFL adhesion treatment, one kind of soaking rubber paste adhesion treatment of immersing in rubber paste and drying, and coating rubber paste adhesion treatment of coating and drying rubber paste on the surface to be the side of toothed belt body 10 Alternatively, two types of rubber paste adhesion processes may be applied, and a rubber paste adhesive layer may be provided on the RFL adhesive layer 14.

  The RFL adhesive layer 14 is formed of the solid content contained in the RFL aqueous solution, and contains resorcin / formalin resin (RF resin) and a rubber component derived from a rubber latex. Further, the RFL adhesive layer 14 contains cellulose-based fine fibers including a fiber diameter distribution range of 50 to 500 nm. The cellulose fine fiber contained in the RFL adhesive layer 14 has the same structure as that contained in the toothed belt main body 10 in the first embodiment. As described above, when the RFL adhesive layer 14 contains the cellulose fine fiber including the distribution range of the fiber diameter of 50 to 500 nm, high adhesion to the toothed belt main body 10 of the tooth portion side reinforcing cloth 12 is obtained. Can.

  In the RFL adhesive layer 14, the cellulose fine fibers are not oriented in a specific direction, and are non-oriented.

  The content of the cellulose-based fine fibers in the RFL adhesive layer 14 is preferably 0.5% by mass or more, and more preferably 1. from the viewpoint of obtaining high adhesiveness of the tooth portion side reinforcing cloth 12 to the toothed belt main body 10. The content is 0% by mass or more, more preferably 2.0% by mass or more, preferably 12% by mass or less, more preferably 10% by mass or less, still more preferably 8% by mass or less.

  The content of the cellulose-based fine fiber with respect to 100 parts by mass of the rubber component in the RFL adhesive layer 14 is preferably 1 part by mass or more, from the viewpoint of obtaining high adhesion to the toothed belt main body 10 of the tooth side reinforcing cloth 12 The amount is preferably 3 parts by mass or more, more preferably 5 parts by mass or more, preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 10 parts by mass or less.

  Note that although it is preferable that the RFL adhesive layer 14 does not contain short fibers having a fiber diameter of 10 μm or more, such short lengths do not inhibit adhesion of the tooth portion side reinforcing cloth 12 to the toothed belt main body 10. Fibers may be included.

  The rubber composition forming the base portion 11a of the toothed belt main body 10 may contain cellulose-based fine fibers as in the first and second embodiments, or may not contain cellulose-based fine fibers. ,either will do. The rubber composition forming the tooth portion 11b of the toothed belt main body 10 may contain cellulose-based fine fibers as in the first and third embodiments, or may not contain cellulose-based fine fibers, either will do.

  The other configuration is the same as that of the first embodiment.

  According to the toothed belt B according to Embodiment 4 of the above configuration, the RFL adhesive layer 14 provided between the tooth portion side reinforcing cloth 12 and the toothed belt main body 10 has a fiber diameter distribution range of 50 to 50. By containing the cellulose fine fiber containing 500 nm, high adhesive strength to the toothed belt main body 10 of the tooth side reinforcing cloth 12 can be obtained, so that the excellent reinforcing effect can be obtained, especially the teeth. Chipping of the part 11 b is suppressed, and as a result, high durability can be obtained.

(Method of manufacturing toothed belt B)
In the method of manufacturing the toothed belt B according to the fourth embodiment, in the material preparation step, the tooth portion side reinforcing cloth 12 ′ is subjected to an adhesion process in the preparation of the tooth portion side reinforcing cloth 12 ′. Specifically, the tooth-part-side reinforcing cloth 12 ′ is subjected to an RFL adhesion process of immersing and heating in an RFL aqueous solution. Moreover, it is preferable to perform the base adhesion | attachment process which is immersed and heated in a base | substrate adhesion process liquid before RFL adhesion process. One or more of the soaking rubber paste adhesion process of dipping in rubber paste and drying after the RFL adhesion process, and the coating rubber paste adhesion process of coating and drying the surface of the toothed belt main body 10 with a rubber paste. Two types of rubber paste bonding may be applied.

<< base adhesion processing >>
The base adhesion treatment liquid is, for example, a solution in which a base adhesion treatment agent such as an epoxy resin or an isocyanate resin (blocked isocyanate) is dissolved in a solvent such as toluene, or a dispersion liquid dispersed in water. The liquid temperature of the base adhesion treatment liquid is, for example, 20 to 30 ° C. The solid content concentration of the base adhesion treatment solution is preferably 20% by mass or less.

  The immersion time in the base adhesion treatment solution is, for example, 1 to 3 seconds. The heating temperature (furnace temperature) after immersion in the base adhesion treatment solution is, for example, 200 to 250 ° C. The heating time (duration in the furnace) is, for example, 1 to 3 minutes. The number of times of base adhesion treatment may be one or two or more. The base adhesive treatment agent adheres to the tooth side reinforcing cloth 12 ', but the amount of adhesion (area weight) is, for example, 0.5 to 8 based on the mass of the fiber material forming the tooth side reinforcing cloth 12'. It is mass%.

<< RFL adhesion process >>
The RFL aqueous solution is an aqueous solution prepared by mixing an initial condensation product of resorcinol and formaldehyde with a rubber latex and a dispersion (gel) in which cellulose fine fibers are dispersed in water. The liquid temperature of the RFL aqueous solution is, for example, 20 to 30 ° C.

  The molar ratio of resorcin (R) to formalin (F) is, for example, R / F = 1/1 to 1/2. Examples of the rubber latex include vinylpyridine-styrene-butadiene rubber latex (Vp-St-SBR), chloroprene rubber latex (CR), chlorosulfonated polyethylene rubber latex (CSM) and the like. The solid content mass ratio of the initial condensation product (RF) of resorcin and formaldehyde to the rubber latex (L) is, for example, RF / L = 1/5 to 1/20.

  The solid content concentration of the RFL aqueous solution is preferably 6.0% by mass or more, more preferably 9.0% by mass or more, and preferably 20% by mass or less, more preferably 15% by mass or less.

  The immersion time in the RFL aqueous solution is, for example, 1 to 3 seconds. The heating temperature (furnace temperature) after immersion in the RFL aqueous solution is, for example, 100 to 180. The heating time (duration in the furnace) is, for example, 1 to 5 minutes. The number of times of the RFL bonding process may be one or two or more. The RFL adhesive layer 14 adheres to the tooth side reinforcing cloth 12 ', but the amount of adhesion (area weight) is, for example, 2 to 5% by mass based on the mass of the fiber material forming the tooth side reinforcing cloth 12'. It is.

  The other methods are the same as in the first embodiment.

Fifth Embodiment
Since the toothed belt B according to the fifth embodiment has the same appearance as that of the first embodiment, the following description will be given based on FIG.

  In the toothed belt B according to the fifth embodiment, an RFL adhesion process in which the tooth portion side reinforcing cloth 12 is immersed and heated in an RFL aqueous solution, a soaking rubber paste adhesion process in which it is immersed in rubber paste and dried, and a toothed belt The surface which becomes the main body 10 side is coated with rubber paste and dried. One or two types of rubber paste adhesion processing are applied among the coating rubber paste adhesion processing. As a result, as shown in FIG. 10, the tooth side reinforcing cloth 12 has the toothed belt main body through the RFL adhesive layer 14 formed by the RFL adhesive process and the rubber paste adhesive layer 15 formed by the rubber paste adhesive process. Glued to ten. In addition, before RFL adhesion processing, the base adhesion processing which consists of the solution which made the base adhesion processing agent such as epoxy resin and isocyanate resin (block isocyanate) dissolve in the solvent such as toluene or disperse it in water. It is preferable that a base adhesion treatment of immersion in liquid and heating is performed, and a base adhesion layer is provided under the RFL adhesion layer 14.

  Similar to Embodiment 1, the RFL adhesive layer 14 contains cellulose fine fibers including a fiber diameter distribution range of 50 to 500 nm, or does not contain such cellulose fine fibers. May be.

  The rubber paste adhesive layer 15 is formed of the solid rubber composition contained in the rubber paste, and the rubber composition forming the rubber paste adhesive layer 15 has a fiber component distribution range of 50 in the rubber component. The uncrosslinked rubber composition in which various rubber compounding agents are blended and kneaded in addition to the cellulose fine fiber containing -500 nm is heated and pressurized, and is crosslinked by the crosslinking agent. As described above, the rubber paste adhesive layer 15 contains cellulose fine fibers including a fiber diameter distribution range of 50 to 500 nm, whereby high adhesion of the tooth portion side reinforcing cloth 12 to the toothed belt main body 10 is obtained. You can get

  As a rubber component of the rubber composition which forms the rubber paste adhesive layer 15, for example, hydrogenated acrylonitrile rubber (H-NBR), hydrogenated acrylonitrile rubber (H-NBR) reinforced with unsaturated carboxylic acid metal salt, ethylene・ Propylene copolymer (EPR), ethylene / propylene / diene terpolymer (EPDM), ethylene / octene copolymer, ethylene-α-olefin elastomer such as ethylene / butene copolymer, chloroprene rubber (CR), and chlorosulfonated polyethylene rubber (CSM Etc.). The rubber component of the rubber composition forming the toothed belt main body 10 is preferably one or two or more of these blended rubbers. The rubber component of the rubber composition forming the rubber paste adhesive layer 15 may be the same as or different from the rubber component of the rubber composition forming the toothed belt main body 10.

  The cellulose-based fine fibers contained in the rubber composition forming the rubber paste adhesive layer 15 have the same configuration as that contained in the toothed belt main body 10 in the first embodiment. In the rubber paste adhesive layer 15, the cellulose fine fibers are not oriented in a specific direction, and are non-oriented.

  The content of the cellulose fine fiber in the rubber paste adhesive layer 15 is preferably 1 mass with respect to 100 mass parts of the rubber component from the viewpoint of obtaining high adhesiveness of the tooth portion side reinforcing cloth 12 to the toothed belt main body 10. The amount is preferably at least 3 parts by mass, more preferably at least 5 parts by mass, and preferably at most 30 parts by mass, more preferably at most 20 parts by mass, and still more preferably at most 10 parts by mass.

  Examples of the rubber compounding agent include a reinforcing material, a friction coefficient reducing material, a crosslinking agent, an antiaging agent and the like.

  As a reinforcing material, for carbon black, for example, channel black; furnace black such as SAF, ISAF, N-339, HAF, N-351, MAF, FEF, SRF, GPF, ECF, N-234, etc .; FT, MT, etc. Thermal black; acetylene black and the like. The reinforcing material also includes silica. The reinforcing material is preferably one or more of these. The content of the reinforcing material is preferably smaller than the content of the reinforcing material in the rubber composition forming the toothed belt main body 10, and for example, 10 to 30 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition. is there.

  Examples of the friction coefficient reducing material include ultra-high molecular weight polyethylene resin powder, fluorocarbon resin powder, and molybdenum. The coefficient of friction reducing material is preferably one or more of these. The content of the friction coefficient reducing material is, for example, 5 to 15 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition.

  Crosslinking agents include sulfur and organic peroxides. As a crosslinking agent, sulfur may be blended, an organic peroxide may be blended, and both of them may be used in combination. The amount of the crosslinking agent is, for example, 0.3 to 5 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition in the case of sulfur, and 100 parts by mass of the rubber component of the rubber composition in the case of an organic peroxide. For example, it is 0.3 to 5 parts by mass.

  As a vulcanization accelerator, for example, thiuram (eg TETD, TT, TRA etc.), thiazole (eg MBT, MBTS etc.), sulfenamide (eg CZ etc), dithiocarbamate (eg BZ-P) Etc.). The vulcanization accelerator is preferably one or more of these. The content of the vulcanization accelerator is, for example, 1 to 3 parts by mass with respect to 100 parts by mass of the rubber component of the rubber composition.

  Examples of the antiaging agent include amine-ketone antiaging agents, diamine antiaging agents, and phenolic antiaging agents. It is preferable that an antiaging agent is 1 type or 2 types or more among these. The content of the antiaging agent is, for example, 1 to 3 parts by mass with respect to 100 parts by mass of the rubber component.

  Although it is preferable that the rubber composition forming the rubber paste adhesive layer 15 does not contain short fibers having a fiber diameter of 10 μm or more, the adhesion of the tooth portion side reinforcing cloth 12 to the toothed belt main body 10 Such short fibers may be included as long as they do not inhibit the

  The rubber composition forming the base portion 11a of the toothed belt main body 10 may contain cellulose-based fine fibers as in the first and second embodiments, or may not contain cellulose-based fine fibers. ,either will do. The rubber composition forming the tooth portion 11b of the toothed belt main body 10 may contain cellulose-based fine fibers as in the first and third embodiments, or may not contain cellulose-based fine fibers, either will do.

  According to the toothed belt B according to Embodiment 5 of the above configuration, the rubber paste adhesive layer 15 provided between the tooth portion side reinforcing cloth 12 and the toothed belt main body 10 has a fiber diameter distribution range of 50. By containing the cellulose fine fiber containing -500 nm, high adhesive strength to the toothed belt main body 10 of the tooth side reinforcing cloth 12 can be obtained, so that the excellent reinforcing effect can be obtained, especially Chipping of the teeth 11b is suppressed, and excellent oil resistance can also be obtained. Furthermore, since the rubber paste adhesive layer 15 contains the cellulose fine fiber containing 50-500 nm of the distribution range of a fiber diameter, the high abrasion resistance of the tooth part side surface can be obtained. As a result, high durability can be obtained.

(Method of manufacturing toothed belt B)
In the method of manufacturing the toothed belt B according to the fifth embodiment, in the material preparation step, the tooth portion side reinforcing cloth 12 ′ is subjected to an adhesion process in the preparation of the tooth portion side reinforcing cloth 12 ′. Specifically, in addition to the RFL adhesion treatment in which the tooth portion side reinforcing cloth 12 'is immersed and heated in an RFL aqueous solution, a soaking rubber paste adhesion treatment in which the rubber paste is immersed and dried, and a toothed belt main body The surface which becomes the 10 side is coated with a rubber paste and dried. In addition, it is preferable to perform the base adhesion process which is immersed in a base adhesion process liquid and heated before RFL adhesion process.

  The base adhesion process is the same as in the fourth embodiment.

<< RFL adhesion process >>
The RFL aqueous solution is an aqueous solution in which a rubber latex is mixed with an initial condensation product of resorcin and formaldehyde. In the case where the cellulose fine fiber is included in the RFL adhesive layer 14, the dispersion (gel) in which the cellulose fine fiber is dispersed in water may be included in the RFL aqueous solution as in the fourth embodiment. The liquid temperature of the RFL aqueous solution is, for example, 20 to 30 ° C. The solid content concentration of the RFL aqueous solution is preferably 30% by mass or less.

  The molar ratio of resorcin (R) to formalin (F) is, for example, R / F = 1/1 to 1/2. Examples of the rubber latex include vinylpyridine-styrene-butadiene rubber latex (Vp-St-SBR), chloroprene rubber latex (CR), chlorosulfonated polyethylene rubber latex (CSM) and the like. The solid content mass ratio of the initial condensation product (RF) of resorcin and formaldehyde to the rubber latex (L) is, for example, RF / L = 1/5 to 1/20.

  The immersion time in the RFL aqueous solution is, for example, 1 to 3 seconds. The heating temperature (furnace temperature) after immersion in the RFL aqueous solution is, for example, 100 to 180 ° C. The heating time (duration in the furnace) is, for example, 1 to 5 minutes. The number of times of the RFL bonding process may be one or two or more. The RFL adhesive layer 14 adheres to the tooth side reinforcing cloth 12 ', but the amount of adhesion (area weight) is, for example, 2 to 5% by mass based on the mass of the fiber material forming the tooth side reinforcing cloth 12'. It is.

Rubber adhesive bonding process
The rubber paste is a solution obtained by dissolving the uncrosslinked rubber composition before crosslinking of the rubber composition containing the cellulose fine fiber forming the rubber paste adhesive layer 15 in a solvent such as toluene. Preparation of rubber paste is performed as follows.

  First, cellulose fine fibers are added to the masticated rubber component and dispersed by kneading.

  Here, as a method of dispersing the cellulose fine fiber in the rubber component, for example, a dispersion (gel) in which the cellulose fine fiber is dispersed in water is added to the rubber component masticated with an open roll, Method of vaporizing water while kneading them, Master of cellulose-based fine fiber / rubber obtained by vaporizing water by mixing dispersion (gel) in which cellulose fine fiber is dispersed in water and rubber latex A method of charging a batch to a rubber component being masticated, a dispersion obtained by dispersing a hydrophobized cellulose fine fiber in a solvent and a solution in which a rubber component is dissolved in a solvent are mixed to obtain a solvent. Method of introducing the master batch of cellulose fine fiber / rubber into the masticating rubber component, lyophilizing a dispersion (gel) in which the cellulose fine fiber is dispersed in water A material obtained by pulverizing, a method of introducing the rubber component is masticated, methods and the like to introduce cellulosic microfibers made hydrophobic in rubber component is masticated.

  Next, while kneading the rubber component and the cellulose fine fiber, various rubber compounding agents are added and kneading is continued to produce an uncrosslinked rubber composition.

  Then, the uncrosslinked rubber composition is put into a solvent and stirred until a uniform solution is obtained to produce a rubber paste. The liquid temperature of the rubber paste is, for example, 20 to 30 ° C.

  The solid content concentration of the rubber paste is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 30% by mass or less, more preferably 20% by mass or less for soaking rubber paste adhesion treatment. is there. For coating rubber paste adhesion processing, it is preferably 10% by mass or more, more preferably 20% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less.

  In the case of the soaking rubber paste adhesion process, the immersion time in the rubber paste is, for example, 1 to 3 seconds. The drying temperature (furnace temperature) after immersion in the rubber paste is, for example, 50 to 100 ° C. The drying time (duration in the furnace) is, for example, 1 to 3 minutes. The number of times of soaking rubber paste adhesion treatment may be one or two or more. The rubber paste adhesive layer 15 adheres to the tooth side reinforcing cloth 12 ', but the amount of adhesion (area weight) is, for example, 2 to 5 mass based on the mass of the fiber material forming the tooth side reinforcing cloth 12'. %.

  In the case of the coating rubber paste adhesion process, the drying temperature (furnace temperature) after coating is, for example, 50 to 100 ° C. The drying time (duration in the furnace) is, for example, 1 to 3 minutes. The number of times of the coating rubber paste adhesion treatment may be one or two or more. The rubber paste adhesive layer 15 adheres to the tooth side reinforcing cloth 12 ', but the amount of adhesion (area weight) is, for example, 2 to 5 mass based on the mass of the fiber material forming the tooth side reinforcing cloth 12'. %.

  The other methods are the same as in the first embodiment.

(Uncrosslinked rubber composition)
The following rubbers 1 to 7 of the uncrosslinked rubber composition for forming a toothed belt main body and rubbers 8 to 14 of the noncrosslinked rubber composition for the rubber paste adhesive layer of the tooth side reinforcing cloth were prepared. Each formulation is also shown in Tables 1 and 2.

<Rubber 1>
First, a dispersion of powdered cellulose (trade name: KC floc W-GK manufactured by Nippon Paper Industries Co., Ltd.) dispersed in toluene is prepared, and the dispersions are made to collide with each other using a high pressure homogenizer to make the powdered cellulose into cellulose fine fibers. By defibrillation, a dispersion liquid in which cellulose fine fibers were dispersed in toluene was obtained. Therefore, cellulose fine fibers are produced by mechanical disintegration means and are not subjected to hydrophobization treatment.

  Next, a dispersion in which cellulose fine fibers are dispersed in toluene, H-NBR (trade name: Zetpol 2020 manufactured by Nippon Zeon Co., Ltd.) is dissolved in toluene, and a plasticizer (trade name: W-260 manufactured by DIC) is added. The resulting solution was mixed, and the toluene and the plasticizer were vaporized to produce a cellulose fine fiber / H-NBR masterbatch. The content of each component in the masterbatch was 25% by mass of cellulose fine fiber, 25% by mass of plasticizer, and 50% by mass of H-NBR.

  Then, while masticating H-NBR, the masterbatch was thrown there and it knead | mixed. When the mixing mass ratio of H-NBR and the masterbatch was 98: 4, and the total H-NBR was 100 parts by mass, the content of the cellulose fine fibers was 1 part by mass.

  Then, H-NBR, cellulose fine fibers, and a plasticizer are kneaded, and 40 parts by mass of FEF carbon black as a reinforcing material (trade name: SEAST SO) with respect to 100 parts by mass of H-NBR. 1 part by mass of stearic acid (trade name: made by NOF Corporation), processing aid, and 5 parts by mass of zinc oxide (trade name: two kinds of zinc oxide manufactured by Fuso Chemical Industry Co., Ltd.) 24 parts by mass of a plasticizer, 5 parts by mass of liquid NBR (Nippon Zeon Co., Ltd., trade name: Nipol 1312) as a co-crosslinking agent, and sulfur of a crosslinking agent (trade name: Oil Sulfur) (0. 5 parts by mass, 2 parts by mass of a thiuram-based vulcanization accelerator (manufactured by Ouchi Emerging Chemical Co., Ltd., trade name: Noxselalar TET-G), and an amine-ketone antioxidant (manufactured by Ouchi Emerging Co., Ltd., trade name: Nocrack 224) 2 mass To prepare uncrosslinked rubber composition by continuing kneading the respective charged. The uncrosslinked rubber composition was designated as rubber 1. In addition, content of the plasticizer in the rubber | gum 1 is 25 mass parts with respect to 100 mass parts of H-NBR combining what was contained in the masterbatch and what was added after that.

<Rubber 2>
An uncrosslinked rubber composition produced in the same manner as the rubber 1 except that the content of the cellulose fine fibers was 3 parts by mass with respect to 100 parts by mass of H-NBR was taken as a rubber 2.

<Rubber 3>
An uncrosslinked rubber composition produced in the same manner as the rubber 1 except that the content of the cellulose fine fibers was 5 parts by mass with respect to 100 parts by mass of H-NBR was taken as a rubber 3.

<Rubber 4>
An uncrosslinked rubber composition produced in the same manner as the rubber 1 except that the content of the cellulose fine fibers was 10 parts by mass with respect to 100 parts by mass of H-NBR was taken as a rubber 4.

<Rubber 5>
An uncrosslinked rubber composition produced in the same manner as the rubber 1 except that the content of the cellulose fine fibers was 15 parts by mass with respect to 100 parts by mass of H-NBR was taken as a rubber 5.

<Rubber 6>
An uncrosslinked rubber composition produced in the same manner as the rubber 1 except that the content of cellulose fine fibers was 25 parts by mass with respect to 100 parts by mass of H-NBR was taken as rubber 6.

<Rubber 7>
While masticating H-NBR, 40 parts by mass of FEF carbon black as a reinforcing material, 1 part by mass of stearic acid as a processing aid, and zinc oxide as a vulcanization accelerating aid with 100 parts by mass of H-NBR 5 parts by mass, 10 parts by mass of plasticizer, 5 parts by mass of liquid NBR of co-crosslinking agent, 0.5 parts by mass of sulfur of crosslinking agent, 2 parts by mass of thiuram vulcanization accelerator, and amine-ketone system An uncrosslinked rubber composition was prepared by charging 2 parts by mass of the anti-aging agent and kneading. The uncrosslinked rubber composition was designated as rubber 7. Thus, the rubber 7 does not contain cellulose fibrils.

<Rubber 8>
Zinc methacrylate reinforced H-NBR (Nippon Zeon Co., Ltd. trade name: Zeoforte ZSC 2295) and H-NBR (Nippon Zeon Co., Ltd. trade name: Zetpole 2020) were mixed with the former and the latter at a mixing mass ratio of 50: 50. And 20 parts by mass of a reinforcing material, FEF carbon black (product name: SEAT SO) manufactured by Tokai Carbon Co., based on 100 parts by mass of these rubber components, and ultra high molecular weight polyethylene powder (Mitsui Made by CHEMICAL Co., Ltd. Brand name: 10 parts by mass of MIPERON XM-220), 0.5 part by mass of sulfur as a crosslinking agent (trade name: Oil Sulfur) manufactured by Nippon Drip Kogyo Co., Ltd. Thiuram-based vulcanization accelerator (Ouchi emerging chemicals 2 parts by mass of Noxceler TET-G), and 2 parts by mass of amine-ketone based anti-aging agent (manufactured by Ouchi Shinko Co., Ltd., trade name: Nocrac 224) An uncrosslinked rubber composition was prepared by kneading and kneading. The uncrosslinked rubber composition was designated as rubber 8. Thus, the rubber 8 does not contain cellulose fibrils.

<Rubber 9>
The zinc methacrylate reinforced H-NBR and H-NBR were masticated, and a masterbatch was added thereto and kneaded. The content of cellulose fine fibers is 1 part by mass when the mixing mass ratio of zinc methacrylate reinforced H-NBR, H-NBR, and masterbatch is 50: 48: 4, and the total H-NBR is 100 parts by mass. It was made to become.

  Then, while kneading the zinc methacrylate reinforced H-NBR, H-NBR, cellulose fine fiber, and plasticizer, there is reinforcement to 100 parts by mass of the zinc methacrylate reinforced H-NBR and H-NBR rubber components. 20 parts by mass of FEF carbon black, 10 parts by mass of ultrahigh molecular weight polyethylene powder, 0.5 parts by mass of sulfur as a crosslinking agent, 2 parts by mass of thiuram-based vulcanization accelerator, and amine-ketone based antioxidant 2 parts by mass of each was charged and kneaded to prepare an uncrosslinked rubber composition. The uncrosslinked rubber composition was designated as rubber 9.

<Rubber 10>
An uncrosslinked rubber composition produced in the same manner as the rubber 9 except that the content of the cellulose fine fibers was 3 parts by mass with respect to 100 parts by mass of the rubber component was used as rubber 10.

<Rubber 11>
An uncrosslinked rubber composition produced in the same manner as the rubber 9 except that the content of the cellulose fine fibers was 5 parts by mass with respect to 100 parts by mass of the rubber component was used as the rubber 11.

<Rubber 12>
An uncrosslinked rubber composition produced in the same manner as the rubber 9 except that the content of the cellulose fine fibers was 10 parts by mass with respect to 100 parts by mass of the rubber component was used as a rubber 12.

<Rubber 13>
An uncrosslinked rubber composition produced in the same manner as the rubber 9 except that the content of the cellulose fine fibers was 15 parts by mass with respect to 100 parts by mass of the rubber component was used as a rubber 13.

<Rubber 14>
An uncrosslinked rubber composition produced in the same manner as the rubber 9 except that the content of the cellulose fine fibers was 25 parts by mass with respect to 100 parts by mass of the rubber component was used as the rubber 14.

(Toothed belt for trial evaluation)
The toothed belts for test evaluation (the tooth pitch 8 mm and the belt width 10 mm) of the following Examples 1 to 13 and Comparative Example 1 were produced. Each configuration is also shown in Table 3.

Example 1
For the toothed belt of Example 1, as the non-crosslinked rubber composition forming the toothed belt main body, rubber 1 containing cellulose fine fibers was used.

  As a tooth side reinforcing cloth, a covering yarn obtained by winding an aramid fiber (trade name: Technora, manufactured by Teijin Ltd.) around urethane yarn to give stretchability as weft and a nylon twist as a warp were used. The woven fabric of the tooth portion side reinforcing cloth was subjected to base adhesion treatment in which it was immersed in an epoxy resin solution and then heated as an adhesion treatment, and RFL adhesion treatment in which it was heated after being immersed in an RFL aqueous solution. In addition, a soaking rubber paste adhesion process of dipping in a rubber paste and drying was repeated twice to the woven fabric of the tooth side reinforcing cloth subjected to the RFL adhesion process. As the rubber paste, one having a solid content concentration of 10% by mass obtained by dissolving the rubber 8 containing no cellulose fine fiber in toluene as a solvent was used. The liquid temperature of the rubber paste was 25 ° C. The immersion time in the rubber paste was 5 seconds. The drying temperature after immersion in the rubber paste was 100 ° C. and the drying time was 40 seconds.

  As the core wire, one made of glass fiber was used.

Example 2
A toothed belt of Example 2 was produced in the same manner as Example 1 except that the rubber 2 containing cellulose fine fibers was used as the non-crosslinked rubber composition forming the toothed belt main body.

Example 3
A toothed belt of Example 3 was produced in the same manner as in Example 1 except that the rubber 3 containing cellulose fine fibers was used as the non-crosslinked rubber composition forming the toothed belt main body.

Example 4
A toothed belt of Example 4 was produced in the same manner as in Example 1 except that the rubber 4 containing cellulose fine fibers was used as the non-crosslinked rubber composition forming the toothed belt main body.

Example 5
A toothed belt of Example 5 was produced in the same manner as in Example 4 except that the rubber paste of the rubber 9 containing cellulose fine fibers was used in the soaking rubber paste adhesion treatment of the tooth side reinforcing cloth.

Example 6
A toothed belt of Example 6 was produced in the same manner as in Example 4 except that the rubber paste of the rubber 10 containing cellulose fine fibers was used in the soaking rubber paste adhesion treatment of the tooth portion side reinforcing cloth.

Example 7
A toothed belt of Example 7 was produced in the same manner as in Example 4 except that the rubber paste of the rubber 11 containing cellulose fine fibers was used in the soaking rubber paste adhesion treatment of the tooth side reinforcing cloth.

Example 8
A toothed belt of Example 8 was produced in the same manner as in Example 4 except that the rubber paste of the rubber 12 containing cellulose fine fibers was used in the soaking rubber paste adhesion treatment of the tooth portion side reinforcing cloth.

Example 9
A toothed belt of Example 9 was produced in the same manner as in Example 4 except that the rubber paste of the rubber 13 containing cellulose fine fibers was used in the soaking rubber paste adhesion treatment of the tooth side reinforcing cloth.

Example 10
A toothed belt of Example 10 was produced in the same manner as in Example 4 except that the rubber paste of the rubber 14 containing cellulose fine fibers was used in the soaking rubber paste adhesion treatment of the tooth portion side reinforcing cloth.

Example 11
A toothed belt of Example 11 was produced in the same manner as in Example 1 except that the rubber 5 containing cellulose fine fibers was used as the non-crosslinked rubber composition forming the toothed belt main body.

Example 12
The toothed belt of Example 12 was produced in the same manner as Example 1 except that the rubber 6 containing cellulose fine fibers was used as the non-crosslinked rubber composition forming the toothed belt main body.

Example 13
As a non-crosslinked rubber composition for forming a toothed belt main body, a rubber paste of rubber 12 containing cellulose fine fibers is used for soaking rubber paste adhesion treatment of reinforcing cloth on tooth side using rubber 7 containing no cellulose fine fibers The toothed belt of Example 13 was produced in the same manner as Example 1 except for the above.

Comparative Example
As a non-crosslinked rubber composition forming the toothed belt main body, a rubber paste of rubber 8 not containing cellulose fine fibers is used for soaking rubber paste adhesion treatment of reinforcing cloth on the tooth side using rubber 7 not containing cellulose fine fibers A toothed belt of a comparative example was produced in the same manner as in Example 1 except for the above.

(Test evaluation method)
<Average fiber diameter and fiber diameter distribution of cellulose fine fiber>
A sample of the rubber composition obtained by crosslinking the rubbers 1 to 6 and the rubbers 9 to 14 is collected from the toothed belt main body and the rubber paste adhesive layer of the toothed belt of Examples 1 to 13, and the sample of the rubber composition is obtained After freeze-pulverizing, the cross section was observed with a scanning electron microscope (SEM), and 50 fibers were arbitrarily selected to measure the fiber diameter, and the number average was determined to obtain the average fiber diameter. Moreover, the maximum value and the minimum value of the fiber diameter were calculated | required among 50 cellulose fine fibers.

<Belt running test>
FIG. 11 shows a pulley layout of the belt travel tester 30.

  The belt traveling test apparatus 30 has a drive pulley 31, a driven pulley 32, and an idler pulley 33. The drive pulley 31 is provided with 21 teeth meshing grooves at the periphery of the pulley. The driven pulley 32 is provided with 42 teeth meshing grooves at the periphery of the pulley. The idler pulley 33 has a flat pulley peripheral edge so as to press the back of the belt. The drive pulley 31, the driven pulley 32, and the idler pulley 33 are all made of carbon steel (S45C).

  With respect to each of the toothed belts B of Examples 1 to 13 and the comparative example, the tooth chipping resistance and the abrasion resistance were evaluated as follows using this belt running tester 30.

-Evaluation of chipping resistance-
The mass of the toothed belt B was measured in advance. Thereafter, the toothed belt B was wound around the belt traveling test machine 30, and a load was applied rearward on the driven pulley 32 to apply a tension of 216 N to the toothed belt B. Then, the tension applied to the toothed belt B is set to 550 N, and the drive pulley 31 is rotated at a rotational speed of 3000 rpm to run the belt, and the running time until the loss of the teeth occurs is the tooth life And The belt running test was performed at room temperature for all of Examples 1 to 13 and Comparative Example, and was also performed at 80 ° C. for Examples 1 to 4, 11 and 12 and Comparative Example.

-Abrasion resistance evaluation-
The toothed belt B was allowed to run for 300 hours under the same conditions as the above-described measurement of the abrasion resistance. After running of the belt, the mass of the toothed belt B was measured again, and the mass difference before and after traveling was calculated as the worn mass.

<Oil resistance test>
About each toothed belt of Examples 1-13 and a comparative example, after measuring mass, it was immersed in new engine oil at 140 ° C for 168 hours. After that, the adhered oil was sufficiently removed by an air gun, and the mass was measured again. The percent change in mass before and after immersion was calculated.

(Test evaluation result)
The test results are shown in Tables 4 and 5. In addition, content of a cellulose fine fiber means the mass part with respect to 100 mass parts of rubber components even if it does not describe in particular below.

<Average fiber diameter and fiber diameter distribution of cellulose fine fiber>
According to Table 4, it can be seen that the cellulose fine fibers contained in the rubber composition obtained by crosslinking the rubbers 1 to 6 and the rubbers 9 to 14 all have a wide distribution of fiber diameters.

<Belt running test>
-Tooth chipping resistance (room temperature)-
In Comparative Example 1 in which no cellulose fine fiber was contained in any of the toothed belt main body and the rubber paste adhesive layer, the tooth portion durable life at room temperature was 384 hours.

  On the other hand, cellulose fine fibers are contained only in the toothed belt main body, and the content thereof is 0 parts by mass, 1 part by mass, 3 parts by mass, 5 parts by mass, 10 parts by mass, 15 parts by mass, and In Examples 1 to 4 and 11 to 12, which are 25 parts by mass, the tooth life of the tooth portion at room temperature was 528 hours, 696 hours, 792 hours, 864 hours, 936 hours, and 1056 hours, respectively. That is, in the range of the present Example, it turns out that tooth part durable life becomes long as content of a cellulose fine fiber increases.

  Moreover, in Examples 4 to 10 in which the content of cellulose fine fibers in the toothed belt main body is the same 10 parts by mass, the tooth life is basically the durable life as the content of cellulose fine fibers in the rubber paste adhesive layer increases. You can see that it is getting longer. Specifically, the content of cellulose fine fibers in the rubber paste adhesive layer in Examples 4 to 10 is 0 parts by mass, 1 part by mass, 3 parts by mass, 5 parts by mass, 10 parts by mass, 15 parts by mass, and The tooth part durability life at room temperature was 864 hours, 912 hours, 960 hours, 1032 hours, 1080 hours, 1128 hours, and 1128 hours, in contrast to 25 parts by mass. In addition, in Example 9 and 10, since tooth part durable life is the same, when content of a cellulose fine fiber is 15 mass parts or more, possibility that the effect which improves tooth part durability is saturated is considered. .

  In addition, in Example 13 in which 10 parts by mass of cellulose fine fiber is contained only in the rubber paste adhesive layer, the tooth part durable life is 456 hours, which is somewhat longer than 384 hours in Comparative Example 1. However, in the case of Example 8 in which the content of cellulose fine fibers in the toothed belt main body is 10 parts by mass, the content of cellulose fine fibers in the rubber paste adhesive layer is the same as in Example 13, but the tooth life It is clear that it is significantly superior to 1080 hours.

  From the above, even when cellulose fine fibers are contained in any of the toothed belt main body and the rubber paste adhesive layer, although the tooth part durable life is improved, the effect is more remarkable when contained in the toothed belt main body I understand that.

-Tooth chipping resistance (80 ° C)-
In Comparative Example 1 in which no cellulose fine fiber is contained in any of the toothed belt main body and the rubber paste adhesive layer, the tooth portion durable life at 80 ° C. is 240 hours.

  On the other hand, cellulose fine fibers are contained only in the toothed belt main body, and the content thereof is 0 parts by mass, 1 part by mass, 3 parts by mass, 5 parts by mass, 10 parts by mass, 15 parts by mass, and In Examples 1 to 4 and 11 to 12 which are 25 parts by mass, the tooth portion durable life at 80 ° C. was in order of 432 hours, 624 hours, 744 hours, 792 hours, 888 hours, and 9126 hours. That is, in the range of the present Example, it turns out that tooth part durable life in high temperature becomes long as content of a cellulose fine fiber increases.

  Moreover, the tooth part durable life at high temperature (80 ° C.) is shorter than that of the tooth part at room temperature. However, it is understood that the deterioration is reduced by containing the cellulose fine fiber. That is, in the comparative example 1, the tooth part durable life at room temperature is 384 hours, whereas the tooth part durable life at 80 ° C. is 240 hours, which is degraded by about 38%. On the other hand, in Example 1 in which 1 part by mass of cellulose fine fibers was contained in the toothed belt main body, the tooth portion durable life at room temperature was 528 hours, whereas the tooth portion durable life at 80 ° C. was 432 It is time, and the deterioration is about 18%. Also in Examples 2, 3, 4, 11 and 12, the deterioration is about 10%, 6%, 8%, 5% and 14% in order, and in any case, when cellulose fine fiber is not included. You can see that it is greatly reduced by comparison.

  Thus, as a factor by which deterioration of the tooth part durable life in high temperature due to the fact that cellulose fine fiber is contained is reduced, decrease of coefficient of linear expansion is considered. That is, the linear expansion coefficient of the toothed belt is reduced by containing the cellulose fine fibers. When the coefficient of linear expansion decreases, the expansion of the teeth at high temperatures is suppressed. As a result, the meshing accuracy between the teeth and the pulleys is maintained even at high temperatures, and an increase in the load on the teeth due to the temperature rise is suppressed, and as a result, deterioration of the tooth life of the teeth at high temperatures is not suppressed. It is guessed.

-Abrasion resistance-
In Comparative Example 1 in which no cellulose fine fiber was contained in any of the toothed belt main body and the rubber paste adhesive layer, the abrasion mass was 4.1 g. Moreover, in Examples 1-4 and 11-12 in which the cellulose fine fiber is contained only in the toothed belt main body, the abrasion mass was 3.9 g to 4.3 g. Therefore, it can be seen that no special improvement in the abrasion resistance can be seen even if the cellulose fine fibers are contained only in the toothed belt main body.

  On the other hand, in Examples 4 to 10 in which the content of cellulose fine fibers in the toothed belt main body is the same 10 parts by mass, the content of cellulose fine fibers in the rubber paste adhesive layer is 0 parts by mass and 1 part by mass, respectively. , 3 parts by weight, 5 parts by weight, 10 parts by weight, 15 parts by weight and 25 parts by weight, while the wear mass is 4.2 g, 3.3 g, 2.5 g, 2.1 g, 1.8 g in order , 1.4 g, and 1.3 g. That is, it can be seen that the wear mass decreases as the content of cellulose fine fibers in the rubber paste adhesive layer increases. Here, if the wear mass is 3.5 g or less, it is considered that the improvement is made to the prior art.

  Moreover, in Example 13 in which the cellulose fine fiber is not contained in the toothed belt main body, 10 parts by mass of the cellulose fine fiber is contained in the rubber paste adhesive layer, and the abrasion mass is 2.0 g, and the resistance is remarkable. It can be seen that the wear resistance is improved.

  From the above, it is considered that the effect of improving the wear resistance is exhibited by the inclusion of the cellulose fine fibers in the rubber paste adhesive layer of the tooth portion side reinforcing cloth.

<Oil resistance test>
In Comparative Example 1 in which no cellulose fine fiber is contained in any of the toothed belt main body and the rubber paste adhesive layer, the mass change before and after oil swelling as an oil resistance evaluation index was 4.4%.

  On the other hand, cellulose fine fibers are contained only in the toothed belt main body, and the content thereof is 0 parts by mass, 1 part by mass, 3 parts by mass, 5 parts by mass, 10 parts by mass, 15 parts by mass, and In Examples 1 to 4 and 11 to 12, which are 25 parts by mass, the mass change amounts are 3.9%, 3.7%, 3.1%, 2.8%, 1.9%, and 1.5 in order. %Met. That is, in the range of the present Example, it turns out that mass change amount becomes small as content of a cellulose fine fiber increases, and oil resistance improves.

  Moreover, in Examples 4 to 10 in which the content of cellulose fine fibers in the toothed belt main body is the same 10 parts by mass, the content of cellulose fine fibers in the rubber paste adhesive layer is 0 parts by mass, 1 part by mass, 3 respectively The mass change amount is 2.8%, 2.8%, 2.7%, 2.6% in order with respect to the parts by mass, 5 parts by mass, 10 parts by mass, 15 parts by mass, and 25 parts by mass. It was 2.3%, 2.2% and 2.1%. That is, it can be seen that, as the content of the cellulose fine fibers in the rubber paste adhesive layer increases, the mass change rate decreases and the oil resistance is improved.

  Moreover, in Example 13 in which 10 parts by mass of cellulose fine fiber is contained only in the rubber paste adhesive layer, the mass change is 4.3%, which is slightly suppressed to 4.4% of Comparative Example 1. There is. In the case of Example 8 in which the content of cellulose fine fibers in the toothed belt main body is 10 parts by mass, the content of cellulose fine fibers in the rubber paste adhesive layer is the same as Example 13 but the mass change is 2.3 %.

  From the above, oil resistance can be improved by containing cellulose fine fibers in the toothed belt main body, and even when cellulose fine fibers are contained only in the rubber paste adhesive layer of the tooth side reinforcing cloth, the effect is obtained Even if it is small, it is understood that oil resistance improves. In addition, when cellulose fine fibers are contained in the rubber paste adhesive layer in addition to the toothed belt main body, it is understood that the oil resistance is more significantly improved.

  The present disclosure is useful in the technical field of toothed belts.

B Toothed Belt 10 Toothed Belt Body 11a Base 11b Teeth 12 Core Wire 13 Teeth Side Reinforcement Cloth 14 RFL Adhesive Layer 15 Rubber Glue Adhesive Layer

Claims (6)

A toothed belt main body formed of a rubber composition having a flat belt-like base and a plurality of teeth integrally provided on the surface on one side of the base at intervals in the belt length direction;
A tooth side reinforcing cloth attached to the toothed belt main body so as to cover the tooth side surface through an adhesive layer containing a rubber component;
A toothed belt provided with
The rubber composition forming the base, the rubber composition forming the teeth, and at least one of the adhesive layers are teeth containing cellulose-based fine fibers including a fiber diameter distribution range of 83 to 390 nm. Belt attached. In the toothed belt described in claim 1,
A toothed belt, wherein the cellulose fine fiber is produced by mechanical disintegration means. The toothed belt according to claim 1 or 2
The content of the cellulose fine fiber in at least one of the rubber composition forming the base, the rubber composition forming the teeth, and the adhesive layer is 1 to 30 parts by mass with respect to 100 parts by mass of the rubber component Toothed belt that is part by mass. The toothed belt according to any one of claims 1 to 3
A toothed belt, wherein the rubber component of the rubber composition forming the toothed belt main body contains hydrogenated acrylonitrile rubber. The toothed belt according to any one of claims 1 to 4,
A toothed belt comprising a rubber component contained in the adhesive layer comprising hydrogenated acrylonitrile rubber and hydrogenated acrylonitrile rubber reinforced with metal salt of unsaturated carboxylic acid.   The toothed belt according to any one of claims 1 to 5,
  A toothed belt characterized in that a distribution range of fiber diameter of the cellulose fine fiber includes 83 to 400 nm.

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