Tubular member, tubular member unit, intermediate transfer member, and image forming apparatus

1. A tubular member formed of a polyamide resin layer, comprising:

carbon black; and

a semi-aromatic polyamide resin, the semi-aromatic polyamide resin being a polyamide-polyether block copolymer formed by polymerizing a monomer with a polycondensate of an aromatic dicarboxylic compound and an aliphatic diamine compound with an alkyl carbon number in a range of from 9 to 13;

wherein

a curve (T-log 10 η curve) indicating a relationship between a temperature (T (° C.)) and a common logarithm (log 10 η) of melt viscosity (η(Pa·s)) at a shear rate of 608 (1/s) in the polyamide resin layer has a slow-sloped region in which a slope (Δ log 10 η/ΔT) of equal to or greater than about −0.010 and equal to or less than about 0 is present in the range of from log 10 200 to log 10 1000, and

the temperature range of the slow-sloped region is equal to or higher than about 15° C.

2. The tubular member according to claim 1 , wherein the tubular member is formed of a single-layered structure of the polyamide resin layer or a multi-layered structure of two or more layers having at least the polyamide resin layer.

3. The tubular member according to claim 1 , wherein the alkyl carbon number in the aliphatic diamine compound is in a range of from 9 to 12.

4. The tubular member according to claim 1 , wherein the polyamide resin layer includes from about 15 parts by mass to about 30 parts by mass of the carbon black with respect to 100 parts by mass of the semi-aromatic polyamide resin.

5. The tubular member according to claim 1 , wherein a primary average particle diameter of the carbon black is equal to or less than about 25 nm.

6. The tubular member according to claim 1 , wherein a crystallinity of the semi-aromatic polyamide resin is equal to or less than about 30%.

7. A tubular member unit comprising:

the tubular member according to claim 1 ; and

a plurality of rolls on which the tubular member is suspended with a tension applied thereto,

wherein the tubular member unit is detachable from an image forming apparatus.

8. An intermediate transfer member formed of the tubular member according to claim 1 .

9. An image forming apparatus comprising:

an image holding member;

a charging unit that charges the surface of the image holding member;

a latent image forming unit that forms a latent image on the charged surface of the image holding member;

a developing unit that develops the latent image formed on the surface of the image holding member with a toner to form a toner image;

the intermediate transfer member according to claim 8 to which the toner image formed on the surface of the image holding member is transferred;

a primary transfer unit that primarily transfers the toner image formed on the surface of the image holding member to the surface of the intermediate transfer member;

a secondary transfer unit that secondarily transfers the toner image transferred to the surface of the intermediate transfer member to a recording medium; and

a fixing unit that fixes the toner image transferred to the recording medium.