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CN-122018260-A - Electrophotographic photoreceptor, process cartridge, and image forming apparatus

CN122018260ACN 122018260 ACN122018260 ACN 122018260ACN-122018260-A

Abstract

An electrophotographic photoreceptor, a process cartridge, and an image forming apparatus, the electrophotographic photoreceptor comprising a conductive substrate, and a laminated photosensitive layer disposed on the conductive substrate and having a charge generation layer and a charge transport layer, wherein the charge transport layer contains a polyarylate resin having a dicarboxylic acid unit (A) represented by the following formula (A) and a diol unit (B) represented by the following formula (B), the charge generation layer contains chlorogallium phthalocyanine as a charge generation material, and the content of a binder resin in the charge generation layer/the total content of the binder resin and the charge generation material has a value of more than 0.4 and less than 0.7.[ chemical formula 1] formula ((A) Equation (B)

Inventors

  • GAO YANGPING
  • IDE KENTA
  • Kiko Youchi
  • KANO FUYUKI
  • SASAKI TOMOYA
  • IWASAKI MASAHIRO
  • OYAMADA YUKI

Assignees

  • 富士胶片商业创新有限公司

Dates

Publication Date
20260512
Application Date
20250430
Priority Date
20241111

Claims (9)

  1. 1. An electrophotographic photoreceptor comprising: Conductive matrix, and A laminated photosensitive layer disposed on the conductive substrate and having a charge generation layer and a charge transport layer, wherein, The charge transport layer contains a polyarylate resin having a dicarboxylic acid unit (A) represented by the following formula (A) and a glycol unit (B) represented by the following formula (B), The charge generation layer contains chlorogallium phthalocyanine as a charge generation material, The content of the binder resin in the charge generating layer/the total content of the binder resin and the charge generating material has a value of more than 0.4 and less than 0.7, [ Chemical formula 1] In the formula (a), ar A1 and Ar A2 are each independently an aromatic ring which may have a substituent, L A is a single bond or a 2-valent linking group, and n A1 is 0,1 or 2; In the formula (B), ar B1 and Ar B2 are each independently an aromatic ring which may have a substituent, L B is a single bond, an oxygen atom, a sulfur atom or-C (Rb 1 )(Rb 2 )-,n B1 is 0, 1 or 2; rb 1 and Rb 2 are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, or Rb 1 and Rb 2 may be bonded to form a cyclic alkyl group.
  2. 2. The electrophotographic photoreceptor according to claim 1, wherein, The content of the binder resin in the charge generating layer/the total content of the binder resin and the charge generating material has a value of more than 0.43 and less than 0.60.
  3. 3. The electrophotographic photoreceptor according to claim 1 or 2, wherein, The dicarboxylic acid unit represented by the formula (A) comprises at least one selected from the group consisting of a dicarboxylic acid unit (A1) represented by the following formula (A1), a dicarboxylic acid unit (A2) represented by the following formula (A2), a dicarboxylic acid unit (A3) represented by the formula (A3), a dicarboxylic acid unit (A4) represented by the formula (A4) and a dicarboxylic acid unit (A5) represented by the formula (A5), [ Chemical formula 2] In the formula (A1), n 101 is an integer of 0 to 4, and n 101 Ra 101 are each independently an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; In formula (A2), n 201 and n 202 are each independently an integer of 0 to 4, and n 201 Ra 201 and n 202 Ra 202 are each independently an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; In formula (A3), n 301 and n 302 are each independently an integer of 0 to 4, and n 301 Ra 301 and n 302 Ra 302 are each independently an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; In the formula (A4), n 401 is an integer of 0 to 6, and n 401 Ra 401 are each independently an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms; In formula (A5), n 501 、n 502 and n 503 are each independently an integer of 0 to 4, and n 501 Ra 501 、n 502 Ra 502 and n 503 Ra 503 are each independently an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms.
  4. 4. The electrophotographic photoreceptor according to any of claim 1 to 3, wherein, The diol unit represented by the formula (B) comprises at least one selected from the group consisting of a diol unit (B1) represented by the following formula (B1), a diol unit (B2) represented by the formula (B2), a diol unit (B3) represented by the formula (B3), a diol unit (B4) represented by the formula (B4), a diol unit (B5) represented by the formula (B5), a diol unit (B6) represented by the formula (B6), a diol unit (B7) represented by the formula (B7) and a diol unit (B8) represented by the formula (B8), [ Chemical formula 3] [ Chemical formula 4] In the formula (B1), rb 101 is a branched alkyl group having 4 to 20 carbon atoms, rb 201 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Rb 401 、Rb 501 、Rb 801 and Rb 901 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom; In the formula (B2), rb 102 is a linear alkyl group having 4 to 20 carbon atoms, rb 202 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Rb 402 、Rb 502 、Rb 802 and Rb 902 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom; In formula (B3), rb 113 and Rb 213 are each independently a hydrogen atom, a linear alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom, d is an integer of 7 to 15, and Rb 403 、Rb 503 、Rb 803 and Rb 903 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom; In the formula (B4), rb 104 and Rb 204 are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Rb 404 、Rb 504 、Rb 804 and Rb 904 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom; In the formula (B5), ar 105 is an aryl group having 6 to 12 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, rb 205 is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Rb 405 、Rb 505 、Rb 805 and Rb 905 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms or a halogen atom; In formula (B6), rb 116 and Rb 216 are each independently a hydrogen atom, a linear alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom, e is an integer of 4 to 6, and Rb 406 、Rb 506 、Rb 806 and Rb 906 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom; In the formula (B7), rb 407 、Rb 507 、Rb 807 and Rb 907 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom; In formula (B8), rb 408 、Rb 508 、Rb 808 and Rb 908 are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom.
  5. 5. The electrophotographic photoreceptor according to any of claims 1 to 4, wherein, The binder resin in the charge generation layer is a vinyl acetate resin or a polyvinyl butyral resin.
  6. 6. The electrophotographic photoreceptor according to any of claims 1 to 5, wherein, The binder resin in the charge generation layer is a vinyl chloride-vinyl acetate copolymer or a polyvinyl butyral resin.
  7. 7. The electrophotographic photoreceptor according to any of claims 1 to 6, wherein, The charge transport layer also contains a polycarbonate resin.
  8. 8. A process cartridge provided with the electrophotographic photoreceptor as claimed in any one of claim 1 to 7, The process cartridge is attached to and detached from the image forming apparatus.
  9. 9. An image forming apparatus includes: The electrophotographic photoreceptor of any one of claims 1 to 7; A charging device for charging a surface of the electrophotographic photoreceptor; An electrostatic latent image forming device that forms an electrostatic latent image on a surface of the charged electrophotographic photoreceptor; a developing device for developing an electrostatic latent image formed on the surface of the electrophotographic photoreceptor by a developer containing a toner to form a toner image, and And a transfer device for transferring the toner image onto the surface of the recording medium.

Description

Electrophotographic photoreceptor, process cartridge, and image forming apparatus Technical Field The invention relates to an electrophotographic photoreceptor, a process cartridge, and an image forming apparatus. Background Patent document 1 discloses an electrophotographic photoreceptor comprising a charge generating layer and a charge transporting layer in this order on a support, wherein at least one of binder resins in the charge transporting layer is a polyarylate resin, and the thickness of the charge transporting layer is 28 μm or more, and the electrophotographic photoreceptor is characterized in that the charge generating layer contains gallium phthalocyanine and the charge transporting layer contains 5 mass% or more and less than 40 mass% of an antioxidant with respect to the total mass of the binder resins in the charge transporting layer. Patent document 2 discloses an electrophotographic photoreceptor including a conductive substrate and a layered photosensitive layer disposed on the conductive substrate and having a charge generation layer and a charge transport layer, wherein the charge transport layer contains a charge transport material, a polyester resin, and a polycarbonate resin, and the polyester resin contains a polyester resin having a specific structure. Patent document 3 discloses a layered electrophotographic photoreceptor having at least 2 layers of a charge generation layer and a charge transport layer on a conductive support, the electrophotographic photoreceptor being characterized in that the charge generation layer contains a phthalocyanine pigment and a polyarylate resin of a specific structure. Patent document 1 Japanese patent laid-open publication No. 2005-164936 Patent document 2 Japanese patent application laid-open No. 2024-11918 Patent document 3 Japanese patent laid-open No. 2003-202683 Disclosure of Invention The object of the present invention is to provide an electrophotographic photoreceptor having excellent local deterioration inhibition of electrical characteristics after long-term printing, as compared with a case where a charge transport layer contains a polyarylate resin having a dicarboxylic acid unit (a) represented by the following formula (a) and a diol unit (B) represented by the following formula (B), and a charge generation layer contains chlorogallium phthalocyanine as a charge generation material, and the content of a binder resin in the charge generation layer/the total content of the binder resin and the charge generation material is 0.4 or less or 0.7 or more. The means for solving the above problems include the following means. An electrophotographic photoreceptor includes a conductive substrate, and a laminated photosensitive layer disposed on the conductive substrate and having a charge generation layer and a charge transport layer, wherein the charge transport layer contains a polyarylate resin having a dicarboxylic acid unit (A) represented by the following formula (A) and a diol unit (B) represented by the following formula (B), the charge generation layer contains chlorogallium phthalocyanine as a charge generation material, and the value of the content of a binder resin in the charge generation layer/the total content of the binder resin and the charge generation material is greater than 0.4 and less than 0.7. [ Chemical formula 1] In formula (a), ar A1 and Ar A2 are each independently an aromatic ring which may have a substituent, L A is a single bond or a 2-valent linking group, and n A1 is 0, 1 or 2. In the formula (B), ar B1 and Ar B2 are each independently an aromatic ring which may have a substituent, L B is a single bond, an oxygen atom, a sulfur atom or-C (Rb 1)(Rb2)-,nB1 is 0, 1 or 2.rb 1 and Rb 2 are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 12 carbon atoms or an aralkyl group having 7 to 20 carbon atoms, or Rb 1 and Rb 2 may be bonded to form a cyclic alkyl group. <2> The electrophotographic photoreceptor according to <1>, wherein the value of the content of the binder resin in the charge generation layer/the total content of the binder resin and the charge generation material is more than 0.43 and less than 0.60. <3> The electrophotographic photoreceptor according to <1> or <2>, wherein the dicarboxylic acid unit represented by the formula (A) comprises at least one selected from the group consisting of a dicarboxylic acid unit (A1) represented by the following formula (A1), a dicarboxylic acid unit (A2) represented by the formula (A2), a dicarboxylic acid unit (A3) represented by the formula (A3), a dicarboxylic acid unit (A4) represented by the formula (A4) and a dicarboxylic acid unit (A5) represented by the formula (A5). [ Chemical formula 2] In the formula (A1), n 101 is an integer of 0 to 4, and n 101 Ra 101 are each independently an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an alkoxy group having 1 to 6 carbon a