# US 2018/0326680 A1 · Friction transmission belt and manufacturing method therefor

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- Number: US 2018/0326680 A1
- Document ID: US20180326680A1
- Status: Published application
- Kind: A1
- Application number: 16/041,616
- Filed: 2018-07-20
- Published: 2018-11-15
- Earliest claimed: 2016-01-22
- Assignees: Bando Chemical Industries, Ltd.
- Applicants: Bando Chemical Industries, Ltd.
- Inventors: Takayuki Okubo; Hisashi Matsuda; Hideaki Kawahara; Shinji Takahashi
- Web page: https://patentgrep.com/patent/US20180326680A1

## CPC

- B29D 29/08: Toothed driving belts
- B29D 29/103: {Multi-ribbed driving belts}
- F16G 1/10: with textile reinforcement
- F16G 1/12: with metal reinforcement
- F16G 5/08: with textile reinforcement
- F16G 5/10: with metal reinforcement
- F16G 5/20: with a contact surface of special shape, e.g. toothed
- F16G 5/166: {with non-metallic rings (F16G5/18 takes precedence)}
- B29D: PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE (making granules B29B9/00; making preforms B29B11/00)
- F16G: BELTS, CABLES, OR ROPES, PREDOMINANTLY USED FOR DRIVING PURPOSES; CHAINS; FITTINGS PREDOMINANTLY USED THEREFOR

## Abstract

A friction transmission belt has a rubber layer forming a pulley contacting portion. The rubber layer is made of a rubber composition containing a crosslinked rubber component and crosslinked polyolefin particles. Examples of the crosslinked polyolefin particles can contain ultrahigh molecular weight polyolefin particles having an average molecular weight of 500,000 or more.

## Claims

### Claim 1

A friction transmission belt comprising a rubber layer forming a pulley contacting portion, wherein
the rubber layer is made of a rubber composition containing a crosslinked rubber component and crosslinked polyolefin particles.

### Claim 2 (depends on 1)

The friction transmission belt of claim 1, wherein
the crosslinked polyolefin particles contain ultrahigh molecular weight polyolefin particles having an average molecular weight of 500,000 or more and crosslinked.

### Claim 3 (depends on 1)

The friction transmission belt of claim 1, wherein
the crosslinked polyolefin particles contain crosslinked polyethylene particles.

### Claim 4 (depends on 1)

The friction transmission belt of claim 1, wherein
the crosslinked polyolefin particles contain crosslinked polyolefin hollow particles having hollow portions.

### Claim 5 (depends on 1)

The friction transmission belt of claim 1, wherein
a content of the crosslinked polyolefin particles in the rubber composition is 20 parts by mass or more and 100 parts by mass or less with respect to 100 parts by mass of the rubber component.

### Claim 6 (depends on 1)

The friction transmission belt of claim 1, wherein
the rubber composition further contains uncrosslinked polyolefin particles.

### Claim 7 (depends on 1)

The friction transmission belt of claim 1, further comprising
a core rubber portion covered with the rubber layer.

### Claim 8 (depends on 7)

The friction transmission belt of claim 7, wherein
the core rubber portion is made of a rubber composition in which a content of the crosslinked polyolefin particles with respect to 100 parts by mass of a rubber component is smaller than a content of the crosslinked polyolefin particles with respect to 100 parts by mass of the rubber component of the rubber layer, or a rubber composition not containing the crosslinked polyolefin particles.

### Claim 9 (depends on 1)

The friction transmission belt of claim 1, wherein
the rubber layer is made of a porous rubber.

### Claim 10

A method for forming a friction transmission belt comprising a rubber layer forming a pulley contacting portion, wherein
the rubber layer is made of a rubber composition produced by heating and pressing an uncrosslinked rubber composition prepared by mixing a rubber component and crosslinked polyolefin particles, and thereby crosslinking the rubber component.

### Claim 11 (depends on 10)

The method of claim 10, wherein
the crosslinked polyolefin particles are prepared by irradiating uncrosslinked polyolefin particles with radiation.

### Claim 12 (depends on 10)

The method of claim 10, wherein
a state of the crosslinked polyolefin particles before mixture is such that spherical particles coagulate like clusters, and the spherical particles are fused and integrated by the heating and formed into a spherical or ellipsoidal shape.