阅读说明：本技术 传动带 (Transmission belt ) 是由 小林正吾 橘博之 土屋大树 松尾圭一郎 于 2018-05-31 设计创作，主要内容包括：传动带的至少一部分由橡胶组合物形成。橡胶组合物含有橡胶成分、纤维素纳米纤维以及炭黑。相对于橡胶成分100质量份,纤维素纳米纤维的添加量为0.1质量份以上且20质量份以下。相对于橡胶成分100质量份,炭黑的添加量为5质量份以上且80质量份以下。将纤维素纳米纤维的添加量的三倍的值和炭黑的添加量的值合计起来的值为15以上且90以下。(At least a portion of the power transmission belt is formed of a rubber composition. The rubber composition contains a rubber component, cellulose nanofibers, and carbon black. The amount of the cellulose nanofibers added is 0.1 to 20 parts by mass per 100 parts by mass of the rubber component. The amount of carbon black added is 5 to 80 parts by mass per 100 parts by mass of the rubber component. The sum of the value obtained by tripling the amount of cellulose nanofibers and the amount of carbon black added is 15 to 90 inclusive.)

1. A power transmission belt, at least a portion of which is formed of a rubber composition, characterized in that:

the rubber composition contains a rubber component, cellulose nanofibers and carbon black,

the amount of the cellulose nanofibers added is 0.1 to 20 parts by mass based on 100 parts by mass of the rubber component,

the amount of the carbon black added is 5 to 80 parts by mass per 100 parts by mass of the rubber component,

the sum of the value three times the amount of the cellulose nanofibers and the value of the amount of the carbon black is 15 to 90 inclusive.

2. The belt of claim 1, wherein:

the cellulose nanofibers have an average fiber diameter of 1nm or more and 200nm or less.

3. A transmission belt according to claim 1 or 2, wherein:

the carbon black has a nitrogen adsorption specific surface area of 120m²The ratio of the carbon atoms to the carbon atoms is less than g.

4. A transmission belt according to any one of claims 1 to 3, wherein:

the rubber comprises the following components: at least one rubber component selected from the group consisting of ethylene-propylene rubber, ethylene-propylene-diene rubber, ethylene-octene copolymer, ethylene-butene copolymer, chloroprene rubber, chlorosulfonated polyethylene rubber, and hydrogenated nitrile rubber.

5. A transmission belt according to any of claims 1 to 4, wherein:

the cellulose nanofibers comprise TEMPO oxidized cellulose nanofibers.

Technical Field

The present disclosure relates to a power transmission belt.

Background

Various substances are added to the rubber composition constituting the transmission belt in order to obtain target characteristics. For example, patent document 1 discloses a technique for forming at least a compression layer in a v-ribbed belt from a rubber composition containing carbon black and short fibers.

Patent document 1: japanese laid-open patent publication No. 2014-167347

Disclosure of Invention

Various requirements are imposed on various characteristics of a power transmission belt made of a rubber composition. The present disclosure describes a technique for improving the wear resistance and temperature rise of a transmission belt made using a rubber composition.

At least a portion of the power transmission belt of the present disclosure is formed of a rubber composition. The rubber composition contains a rubber component, cellulose nanofibers, and carbon black. The amount of the cellulose nanofibers added is 0.1 to 20 parts by mass per 100 parts by mass of the rubber component. The amount of carbon black added is 5 to 80 parts by mass per 100 parts by mass of the rubber component. The sum of the value obtained by tripling the amount of cellulose nanofibers and the amount of carbon black added is 15 to 90 inclusive.

Effects of the invention

According to the transmission belt of the present disclosure, the wear resistance of the transmission belt can be improved and the temperature rise of the transmission belt can be suppressed.

Drawings

Fig. 1 is a perspective view schematically illustrating a v-ribbed belt in an embodiment of the present disclosure;

fig. 2 is a sectional view of a main portion of the v-ribbed belt in the embodiment;

fig. 3 is a first explanatory view showing a manufacturing method of the v-ribbed belt in the embodiment;

fig. 4 is a second explanatory view showing a manufacturing method of the v-ribbed belt in the embodiment;

fig. 5 is a third explanatory view showing a manufacturing method of the v-ribbed belt in the embodiment;

fig. 6 is a fourth explanatory view showing a manufacturing method of the v-ribbed belt in the embodiment;

fig. 7 is a fifth explanatory view showing a manufacturing method of the v-ribbed belt in the embodiment;

fig. 8 is a sixth explanatory view showing a manufacturing method of the v-ribbed belt in the embodiment;

fig. 9 is a perspective view schematically showing a flat belt in the embodiment;

fig. 10 is a first explanatory view showing a manufacturing method of a flat belt in the embodiment;

fig. 11 is a second explanatory view showing a manufacturing method of a flat belt in the embodiment;

fig. 12 is a third explanatory view showing a method of manufacturing a flat belt in the embodiment;

FIG. 13 is a perspective view schematically illustrating a single-sided toothed V-belt in an embodiment;

FIG. 14 is a view schematically showing a wrapping cloth V belt, a trim V belt, and a timing belt in the embodiment;

fig. 15 schematically shows a belt running test machine for evaluating the abrasion resistance and belt temperature of a belt.

Detailed Description

Next, embodiments of the present disclosure will be explained.

(rubber composition)

The rubber composition according to the present embodiment is a rubber composition in which an uncrosslinked rubber composition containing cellulose nanofibers (hereinafter, referred to as "CNF") and carbon black (hereinafter, referred to as "CB") is dispersed in a rubber component, and the rubber component is crosslinked by heating and pressurizing the uncrosslinked rubber composition. The content of CNF is preferably 0.1 part by mass or more and 20 parts by mass or less, and more preferably 1 part by mass or more and 10 parts by mass or less, with respect to 100 parts by mass of the rubber component. The content of CB is preferably 5 parts by mass or more and 80 parts by mass or less, and more preferably 10 parts by mass or more and 40 parts by mass or less, with respect to 100 parts by mass of the rubber component.

A value obtained by summing up a value three times the content (parts by mass) of CNF with respect to 100 parts by mass of the rubber component and a value of the content (parts by mass) of CB with respect to 100 parts by mass of the rubber component is preferably 15 or more and 90 or less, and more preferably 25 or more and 70 or less.

According to the rubber composition of the above embodiment, heat generation of the transmission belt can be suppressed during dynamic use, and excellent wear resistance can be obtained.

Examples of the rubber component include ethylene- α -olefin elastomers such as ethylene-propylene rubber (EPR), ethylene-propylene-diene rubber (EPDM), ethylene-octene copolymers, and ethylene-butene copolymers, Chloroprene Rubber (CR), chlorosulfonated polyethylene rubber (CSM), and hydrogenated nitrile rubber (H-NBR).

In the case of using CR as the rubber component, it is preferable that CR is a main component and the content of CR in the rubber component is more than 50 mass%. Further, from the viewpoint of suppressing heat generation and obtaining excellent abrasion resistance, the content of CR in the rubber component is preferably 80% by mass or more, more preferably 90% by mass or more, and most preferably 100% by mass.

Examples of CR include G-type sulfur-modified CR, W-type thiol-modified CR, A-type highly crystalline CR, low viscosity CR, and carboxylated CR. The CR contained in the rubber component preferably contains one or two or more of the above-mentioned CRs, and from the viewpoint of suppressing heat generation during dynamic use and obtaining excellent abrasion resistance, it more preferably contains sulfur-modified CR, further preferably contains sulfur-modified CR as a main component, and further more preferably consists of only sulfur-modified CR. Most preferably, the rubber component consists only of sulfur-modified CR.

CNF is composed of a skeletal component of plant cell walls obtained by breaking apart plant fibers very finely. As the raw material slurry of CNF, for example, slurry of wood, bamboo, pefurazone (straw), potato, sugar cane (bagasse), waterweed, seaweed, and the like is given. Among them, wood pulp is preferred.

Examples of CNF include TEMPO oxidation CNF and mechanical defibration CNF. The CNF preferably contains one or two of the CNFs, more preferably TEMPO-oxidized CNF, still more preferably TEMPO-oxidized CNF as a main component, and still more preferably consists of only TEMPO-oxidized CNF.

TEMPO oxidation CNF is CNF obtained by selectively oxidizing a hydroxyl group at C6 in a cellulose molecule to a carboxyl group by allowing a co-oxidant to act on cellulose contained in a raw material slurry with an N-oxyl compound as a catalyst, and mechanically refining the carboxyl group. Examples of the N-oxyl compound include radicals of 2,2,6, 6-tetramethylpiperidin-1-oxyl (TEMPO) and 4-acetamido-TEMPO. Examples of the co-oxidizing agent include hypohalous acids and salts thereof, perhalogenic acids and salts thereof, hydrogen peroxide, and perhydroorganic acids. The mechanical defibration CNF is a CNF obtained by pulverizing a raw material slurry by a defibrating apparatus such as a kneader such as a twin-screw kneader, a high-pressure homogenizer, a grinder, or a bead mill.

The fiber diameter of the TEMPO oxidized CNF is, for example, 1nm to 10nm, and the distribution is narrow. On the other hand, the fiber diameter of the mechanical defibration CNF is several tens nm to several hundreds nm, and the distribution thereof is wide. Therefore, it is possible to clearly distinguish between the TEMPO oxidized CNF and the mechanical defibered CNF according to the size of the fiber diameter and the distribution thereof.

The average fiber diameter of the CNF contained in the rubber composition in the present embodiment is 1nm or more and 200nm or less. More preferably 1nm to 50nm, still more preferably 1nm to 20 nm.

The CNF may contain hydrophobized CNF that has been subjected to a hydrophobization treatment. Examples of the hydrophobized CNF include a CNF in which a part or all of carboxyl groups in cellulose are replaced with a hydrophobic group, and a CNF subjected to a hydrophobization surface treatment with a surface treatment agent. Examples of hydrophobization for obtaining CNF in which a part or all of the hydroxyl groups in cellulose are replaced with hydrophobic groups include esterification, alkylation, tosylation, epoxidation, and arylation. Among them, esterification is preferable. Specifically, the esterified hydrophobized CNF is a CNF obtained by acylating a part or all of hydroxyl groups in cellulose with a carboxylic acid such as acetic acid, acetic anhydride, propionic acid, or butyric acid, or a halide thereof. Examples of the surface treatment agent for obtaining the CNF subjected to the hydrophobic surface treatment with the surface treatment agent include a silane coupling agent.

As the CB, CB having an iodine adsorption specific surface area of 120 or less is used. More preferably, CB having an iodine adsorption specific surface area of 80 or less, and still more preferably CB having an iodine adsorption specific surface area of 50 or less. Examples include: channel black; furnace black such as ISAF, N-339, HAF, N-351, MAF, FEF, SRF, GP and the like; thermal cracking carbon black such as FT and MT; acetylene black, and the like. The CB preferably contains one or two or more of the above carbon blacks. More preferably, the composition contains FEF, still more preferably contains FEF as a main component, and still more preferably consists of FEF alone.