Electrophotographic photosensitive member, process cartridge, electrophotographic apparatus, and method of producing electrophotographic photosensitive member

• US 8,956,792 B2
• Filed: 04/10/2012
• Issued: 02/17/2015
• Est. Priority Date: 04/14/2011
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Okuda, Atsushi, Ogaki, Harunobu, Noguchi, Kazunori, Anezaki, Takashi, Shida, Kazuhisa, Murai, Shio
• Primary Examiner(s): Vajda, Peter
• Assistant Examiner(s): GODO, OLATUNJI A
• Application Number:
  US13/443,701
• Publication Number:
  US 20120263494A1
• Time in Patent Office: 1,043 Days
• Field of Search: 430/59.6, 430/58.8, 430/58.2, 430/58.5, 430/58.65, 430/58.75, 430/58.85, 399/159
• US Class Current: 430/58.8
• CPC Class Codes: G03G 5/0564 Polycarbonates
• CPC Class Codes: G03G 5/0578 Polycondensates comprising silicon atoms in the main chain
• CPC Class Codes: G03G 5/14756 Polycarbonates
• CPC Class Codes: G03G 5/14773 Polycondensates comprising silicon atoms in the main chain

Abstract

Provided is an electrophotographic photosensitive member which is excellent in terms of both continuous reduction of contact stress with contact members and the like and potential stability during repeated use. A charge transport layer which serves as a surface layer of an electrophotographic photosensitive member has a matrix-domain structure including a matrix containing a component [β] (polycarbonate resin D having a specific repeating structural unit) and a charge-transporting substance and domains containing a component [α] (polycarbonate resin A having a repeating structural unit including a specific siloxane moiety).

Claims

1. An electrophotographic photosensitive member comprising a support, a charge generation layer provided on the support, and a charge transport layer provided on the charge generation layer, the charge transport layer serving as a surface layer, the electrophotographic photosensitive member being characterized in that

the charge transport layer has a matrix-domain structure including:

a matrix containing a component [β

] described below and a charge-transporting substance, and

domains containing a component [α

] described below,

wherein component [α

] comprises a polycarbonate resin A which has a repeating structural unit represented by the formula (A) below, a repeating structural unit represented by the formula (B) below, and a repeating structural unit represented by the formula (C) below and in which the content of a siloxane moiety is 5% to 40% by mass, the content of the repeating structural unit represented by the formula (B) below is 10% to 30% by mass, and the content of the repeating structural unit represented by the formula (C) below is 25% to 85% by mass;

2. The electrophotographic photosensitive member according to claim 1, wherein the content of the siloxane moiety in the charge transport layer is 1% to 20% by mass relative to the total mass of all the resins in the charge transport layer.

3. A process cartridge characterized by integrally holding the electrophotographic photosensitive member according to claim 1 and at least one means selected from the group consisting of charging means, developing means, transferring means, and cleaning means, and by being detachably mountable to a main body of an electrophotographic apparatus.

4. An electrophotographic apparatus characterized by comprising the electrophotographic photosensitive member according to claim 1, charging means, exposing means, developing means, and transferring means.

5. A method of producing the electrophotographic photosensitive member according to claim 1, the method being characterized by comprising a step of applying a charge transport layer coating solution containing the components [α

] and [β

] and a charge-transporting substance onto the charge generation layer, followed by drying to form the charge transport layer.

6. The electrophotographic photosensitive member according to claim 1,

wherein the charge-transporting substance is at least one selected from the group consisting of:

a compound having a structure represented by the formula (1a),

a compound having a structure represented by the formula (1a′

),

a compound having a structure represented by the formula (1b), and

a compound having a structure represented by the formula (1b′

),