Method for preparing electrophotographic photosensitive member

• US 7,629,102 B2
• Filed: 02/04/2008
• Issued: 12/08/2009
• Est. Priority Date: 07/17/2007
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Noguchi, Kazunori, Ochi, Atsushi, Uematsu, Hiroki, Ogaki, Harunobu, Kawahara, Masataka
• Primary Examiner(s): LE, HOA VAN
• Application Number:
  US12/025,399
• Publication Number:
  US 20090023091A1
• Time in Patent Office: 673 Days
• Field of Search: 430/127, 430/132
• US Class Current: 430/127
• CPC Class Codes: G03G 5/047 characterised by the charge-generation layers or charge transport layers G03G5/0433 and G03G5/0436 take precedence
• CPC Class Codes: G03G 5/0525 Coating methods
• CPC Class Codes: G03G 5/147 Cover layers

Abstract

A method for preparing in high productivity and stably an electrophotographic photosensitive member having depressed portions on its surface, is provided. The method is characterized in that a coating liquid for a surface layer which includes a solvent including a hydrophilic solvent and a hydrophobic solvent and a polymer compound soluble in the hydrophobic solvent is used; the hydrophilic solvent has a boiling point equal to or higher than that of the hydrophobic solvent; the hydrophilic solvent has a dipole moment of 0 or more and less than 2.8, obtained by a structure optimized calculation using a semiempirical molecular orbital calculation; the total mass of the hydrophobic solvent is 50 mass % or more and less than 100 mass % of the total mass of the solvent included in the coating liquid for a surface layer; and after the coating liquid for a surface layer is applied, the depressed portions are formed by condensation on the surface on which the coating liquid for a surface layer is applied.

Claims

1. A method for preparing an electrophotographic photosensitive member having depressed portions on a surface thereof, wherein a coating liquid for a surface layer which comprises a solvent comprising a hydrophilic solvent and a hydrophobic solvent and a polymer compound soluble in the hydrophobic solvent is used;

the hydrophilic solvent has a boiling point equal to or higher than that of the hydrophobic solvent;

the hydrophilic solvent has a dipole moment of 0 or more and less than 2.8, obtained by a structure optimized calculation using a semiempirical molecular orbital calculation;

the total mass of the hydrophobic solvent is 50 mass % or more and less than 100 mass % of the total mass of the solvent comprised in the coating liquid for a surface layer; and

after the coating liquid for a surface layer is applied, the depressed portions are formed by condensation on the surface on which the coating liquid for a surface layer is applied.

2. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophobic solvent has a dipole moment of 0 or more and 1.0 or less, obtained by the structure optimized calculation using the semiempirical molecular orbital calculation.

3. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophobic solvent has a boiling point equal to or higher than 100°

C.

4. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophobic solvent is an aromatic organic solvent.

5. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the polymer compound soluble in the hydrophobic solvent is either one or both of a polycarbonate resin and an aromatic polyester resin.

6. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophobic solvent is at least one solvent selected from the group consisting of methylbenzene, ethylbenzene, 1,2-dimethylbenzene, 1,3-dimethylbenzene, 1,4-dimethylbenzene, 1,3,5 -trimethylbenzene and chlorobenzene.

7. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophilic solvent is a compound comprising at least one of at least one kind of functional groups selected from the group consisting of a carbonyl group, a hydroxyl group and an amide group.

8. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophilic solvent is a compound comprising at least two hydroxyl groups, two amide groups or a hydroxyl group and an amide group.

9. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophilic solvent is a polymer comprising either one or both of a hydroxyl group and an amide group as a repeating unit.

10. The method for preparing an electrophotographic photosensitive member according to claim 1, wherein the hydrophilic solvent is at least one solvent selected from the group consisting of diethylene glycol diethyl ether, N,N,N′

,N′

-tetramethylurea, 2-ethoxyethanol, 2-(methoxymethoxy) ethanol, 2-butoxyethanol, tetrahydrofurfuryl alcohol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol, polyethylene glycol and N,N,N′

,N′

-tetramethylethylenediamine.