Polyimide tube, method for producing same, and fixing belt

Patent metadata

Field	Value
Publication number	US-9335689-B2
Application number	US-201214111190-A
Country	US
Kind code	B2
Filing date	Nov 14, 2012
Priority date	Nov 29, 2011
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

Provided are a polyimide tube that can be produced at a low cost and has good durability and a good offset property, a method for producing the polyimide tube, and a fixing belt which includes the polyimide tube as a base and which has good durability and a good offset property. Provided are a polyimide tube including a base resin containing a polyimide resin having good rigidity and a soft polyimide resin having good flexibility in a mass ratio of 30:70 to 70:30, 20% to 50% by volume of graphite, 3% by volume or more of a highly conductive carbon black particle, and 0.5% by volume or more of a carbon nanotube relative to the volume of the base resin, a method for producing the polyimide tube, and a fixing belt including the polyimide tube as a base.

First claim

The invention claimed is:

1. A polyimide tube comprising:
a base resin containing a polyimide resin A including, as a main constitutional unit, a repeating unit represented by formula (A) below:

and a polyimide resin B including, as a main constitutional unit, a repeating unit represented by formula (B) below:

and/or a polyimide resin C including, as a main constitutional unit, a repeating unit represented by formula (C) below:

in which a ratio (polyimide resin A):(polyimide resin B +polyimide resin C) is 30:70 to 70:30 in terms of mass ratio;
20% to 50% by volume of graphite; 3% by volume or more of a highly conductive carbon black particle; and 0.5% by volume or more of a carbon nanotube relative to the volume of the base resin,
the highly conductive carbon black particle is a carbon black particle in which a mixture prepared by mixing the carbon black particle with a high-density polyethylene resin in an amount of 10% by mass can have a volume resistance of 20 Ω cm or less.

2. The polyimide tube according to claim 1 , wherein the ratio polyimide resin A:(polyimide resin B +polyimide resin C) is 50:50 to 60:40 in terms of mass ratio.

3. The polyimide tube according to claim 1 , wherein 30% to 40% by volume of the graphite, 5% to 10% by volume of the highly conductive carbon black particle, and 1% to 3% by volume of the carbon nanotube are contained relative to the volume of the base resin.

4. The polyimide tube according to claim 1 , having a thickness of 10 to 150 μm.

5. A method for producing the polyimide tube according to claim 1 , the method comprising:
a step of making/bringing a discharge opening of a supply portion of a dispenser close to/into contact with an outer surface of a columnar core body or an outer surface or an inner surface of a cylindrical core body, and
while rotating the core body and relatively moving the discharge opening in a direction of a rotational axis of the core body,
forming a coating layer by continuously supplying a polyimide varnish from the discharge opening onto the outer surface of the columnar core body or the outer surface or the inner surface of the cylindrical core body;
after the formation of the coating layer, a step of solidifying the coating layer; and
after the solidification, a step of detaching the coating layer from the core body.

6. A fixing belt comprising a belt base including the polyimide tube according to claim 1 , and a fluororesin layer disposed on an outer circumferential surface of the belt base either directly or with an adhesive layer therebetween.

Assignees

• Sumitomo Electric Industries
• Sumitomo Elec Fine Polymer Inc

Inventors

• Nakajima Shingo
• Sugawara Jun
• Ikeda Yoshitaka
• Shoji Daisuke

Classifications

• C08G73/1071

  Wholly aromatic polyimides containing oxygen in the form of ether bonds in the main chain · CPC title

• B32B2270/00

  Resin or rubber layer containing a blend of at least two different polymers · CPC title

• C08G73/1067

  Wholly aromatic polyimides, i.e. having both tetracarboxylic and diamino moieties aromatically bound · CPC title

• G03G15/20

  for fixing, e.g. by using heat · CPC title

• C08K7/24

  inorganic · CPC title