Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus

• US 6,093,515 A
• Filed: 08/27/1998
• Issued: 07/25/2000
• Est. Priority Date: 08/29/1997
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yoshida, Akira, Anayama, Hideki
• Primary Examiner(s): GOODROW, JOHN L
• Application Number:
  US09/141,416
• Time in Patent Office: 698 Days
• Field of Search: 430/48, 430/58, 430/59, 430/66, 430/96, 399/159
• US Class Current: 430/96
• 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

An electrophotographic photosensitive member, comprising a support and a photosensitive layer disposed on the support. The photosensitive member has a surface layer comprising a siloxane polymer which comprises at least two polysiloxane units each independently represented by a formula (1) (shown in the specification) and has a molecular structure such that adjacent two polysiloxane units of the formula (1) are connected with each other at their side chains by --O--Pc--CO--O-- where Pc denotes a polycarbonate chain. Such a molecular structure of the siloxane polymer is effective in improving lubricating properties of the surface of the photosensitive member while retaining a mechanical strength thereof.

Claims

1. An electrophotographic photosensitive member, comprising:

a support and a photosensitive layer disposed on the support, wherein

said photosensitive member has a surface layer comprising a siloxane polymer which comprises at least two polysiloxane units each independently represented by a formula (1) shown below and has a molecular structure such that adjacent two polysiloxane units of the formula (1) are connected with each other at their side chains by --O--Pc--CO--O-- where Pc denotes a polycarbonate chain;

##STR17## wherein R₁, R₂, R₅ and R₆ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group;

R₃ and R₄ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, or a divalent group represented by the following formula (2);

##STR18## wherein R₇ to R₁₁ independently denote a single bond, hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group;

one of R₇ to R₁₁ being a single bond and at least one of R₃ and R₄ groups connected with (SiO)_n being said divalent group of the formula (2); and

m and n independently denote a positive integer.

2. A member according to claim 1, wherein said polycarbonate chain Pc has a recurring unit represented by the following formula (3):

##STR19## wherein X₁ denotes a single bond, --O--, --S--, or substituted or unsubstituted alkylidene group; and

R₁₂ to R₁₉ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group.

3. A member according to claim 1, wherein said siloxane polymer comprises a product obtained from a siloxane compound represented by a formula (4) shown below, a bisphenol compound represented by a formula (5) shown below, and phosgene:

##STR20## wherein R₂₀ to R₂₇ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group, at least one of R₂₃ and R₂₄ groups connected with (SiO)_q being substituted or unsubstituted phenyl group having hydroxyl group, and p and q independently denote a positive integer; and

##STR21## wherein X₂ denotes a single bond, --O--, --S--, substituted or unsubstituted alkylidene group; and

R₂₈ to R₃₅ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group.

4. A member according to claim 1, wherein said surface layer further comprises a polycarbonate resin.

5. A member according to claim 4, wherein said polycarbonate resin has a recurring unit represented by the following formula (6):

##STR22## wherein X₃ denotes a single bond, --O--, --S--, substituted or unsubstituted alkylidene group; and

R₃₆ to R₄₃ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group.

6. A process cartridge detachably mountable to an electrophotographic apparatus main body, comprising:

an electrophotographic photosensitive member and at least one means selected from the group consisting of charging means, developing means and cleaning means, wherein

said electrophotographic photosensitive member, comprises a support and a photosensitive layer disposed on the support, and

said photosensitive member has a surface layer comprising a siloxane polymer which comprises at least two polysiloxane units each independently represented by a formula (1) shown below and has a molecular structure such that adjacent two polysiloxane units of the formula (1) are connected with each other at their side chains by --O--Pc--CO--O-- where Pc denotes a polycarbonate chain;

##STR23## wherein R₁, R₂, R₅ and R₆ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group;

R₃ and R₄ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, or a divalent group represented by the following formula (2);

##STR24## wherein R₇ to R₁₁ independently denote a single bond, hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group;

one of R₇ to R₁₁ being a single bond and at least one of R₃ and R₄ groups connected with (SiO)_n being said divalent group of the formula (2); and

m and n independently denote a positive integer.

7. An electrophotographic apparatus, comprising:

an electrophotographic photosensitive member, charging means, exposure means, developing means and transfer means, wherein

said electrophotographic photosensitive member, comprises a support and a photosensitive layer disposed on the support, and

said photosensitive member has a surface layer comprising a siloxane polymer which comprises at least two polysiloxane units each independently represented by a formula (1) shown below and has a molecular structure such that adjacent two polysiloxane units of the formula (1) are connected with each other at their side chains by --O--Pc--CO--O-- where Pc denotes a polycarbonate chain;

##STR25## wherein R₁, R₂, R₅ and R₆ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group;

R₃ and R₄ independently denote hydrogen, halogen, substituted or unsubstituted alkyl group, substituted or unsubstituted aryl group, or a divalent group represented by the following formula (2);

##STR26## wherein R₇ to R₁₁ independently denote a single bond, hydrogen, halogen, substituted or unsubstituted alkyl group, or substituted or unsubstituted aryl group;

one of R₇ to R₁₁ being a single bond and at least one of R₃ and R₄ groups connected with (SiO)_n being said divalent group of the formula (2); and

m and n independently denote a positive integer.