Resin member and wearable band

1. A resin member having a longitudinal direction and a plane, the resin member comprising:

a first base portion that extends in the longitudinal direction;

a stretchable portion having an extending portion that extends in a direction that crosses the longitudinal direction, the extending portion extending along the plane; and

a second base portion that extends in the longitudinal direction, and is connected to the first base portion through the stretchable portion,

wherein when the resin member is stretched in the longitudinal direction, an angle formed between the longitudinal direction and the direction in which the extending portion extends changes, and

the material of the stretchable portion contains a cellulose fiber and a resin.

2. The resin member according to claim 1 , wherein the cellulose fiber is dyed.

3. The resin member according to claim 1 , wherein the cellulose fiber has a diameter of 4.0 nm or more and 1.0 μm or less.

4. The resin member according to claim 1 , wherein the cellulose fiber has an aspect ratio of 100 or more.

5. The resin member according to claim 1 , wherein the resin is an elastomer.

6. The resin member according to claim 1 , wherein the resin is one type or a mixture of two or more types selected from a urethane-based resin, a silicone-based resin, a styrenic resin, an ester-based resin, an olefinic resin, a fluorine-based resin, and a diene-based resin.

7. The resin member according to claim 1 , wherein the cellulose fiber is contained in an amount of 0.1 mass % or more and 50.0 mass % or less with respect to the total amount of the resin member.

8. The resin member according to claim 1 , wherein the cellulose fiber has a molecular structure represented by the following formula (I):

wherein n represents an integer of 10 or more and 100000 or less.

9. A wearable band, comprising the resin member according to claim 1 .

10. A resin member having a longitudinal direction, the resin member comprising:

a first end; and

an opposite second end that are connected by a stretchable portion, the stretchable portion including:

a first pair of arms that each extend in a direction transverse to the longitudinal direction toward a center of the resin member, and a first connection arm that extends in the longitudinal direction between terminal ends of the first pair of arms; and

a second pair of arms that extend toward the first pair of arms in the direction transverse to the longitudinal direction toward the center of resin member, and a second connection arm that extends in the longitudinal direction between terminal ends of the second pair of arms,

wherein the first and second connection arms extend parallel to each other and are spaced apart by a gap,

wherein, when the resin member is stretched in the longitudinal direction, an angle at which the first and second pair of arms each extend changes, and

the material of the stretchable portion contains a cellulose fiber and a resin.

11. The resin member according to claim 10 , wherein the cellulose fiber is dyed.

12. The resin member according to claim 10 , wherein the cellulose fiber has a diameter of 4.0 nm or more and 1.0 μm or less.

13. The resin member according to claim 10 , wherein the cellulose fiber has an aspect ratio of 100 or more.

14. The resin member according to claim 10 , wherein the resin is an elastomer.

15. The resin member according to claim 10 , wherein the resin is one type or a mixture of two or more types selected from a urethane-based resin, a silicone-based resin, a styrenic resin, an ester-based resin, an olefinic resin, a fluorine-based resin, and a diene-based resin.

16. The resin member according to claim 10 , wherein the cellulose fiber is contained in an amount of 0.1 mass % or more and 50.0 mass % or less with respect to the total amount of the resin member.

17. The resin member according to claim 10 , wherein the cellulose fiber has a molecular structure represented by the following formula (I):

wherein n represents an integer of 10 or more and 100000 or less.

18. A wearable band, comprising the resin member according to claim 10 .