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CN-122018258-A - Electrophotographic photoreceptor, process cartridge, and image forming apparatus

CN122018258ACN 122018258 ACN122018258 ACN 122018258ACN-122018258-A

Abstract

An electrophotographic photoreceptor, a process cartridge, and an image forming apparatus, the electrophotographic photoreceptor including a conductive substrate, a charge generation layer disposed on the conductive substrate, and a charge transport layer disposed on the charge generation layer, wherein the charge transport layer contains a phenol compound, a polyarylate resin, a polycarbonate resin, and a charge transport material, and a vector distance DIS HT （J/cm 3 ） 1/2 between an HSP value of the charge transport material and an HSP value of the polyarylate resin and a vector distance DIS PC （J/cm 3 ） 1/2 between an HSP value of the polycarbonate resin and an HSP value of the polyarylate resin calculated from Hansen solubility parameters satisfy the following formulas (1) and (2), respectively. Formula (1) DIS HT is less than or equal to 3.9 formula (2) 9.2 is less than or equal to DIS PC <12.0

Inventors

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

Assignees

  • 富士胶片商业创新有限公司

Dates

Publication Date
20260512
Application Date
20251010
Priority Date
20241111

Claims (13)

  1. 1. An electrophotographic photoreceptor comprising a conductive substrate, a charge generation layer disposed on the conductive substrate, and a charge transport layer disposed on the charge generation layer, The charge transport layer contains a phenol compound, a polyarylate resin, a polycarbonate resin, and a charge transport material, wherein a vector distance DIS HT （J/cm 3 ） 1/2 between the HSP value of the charge transport material and the HSP value of the polyarylate resin and a vector distance DIS PC （J/cm 3 ） 1/2 between the HSP value of the polycarbonate resin and the HSP value of the polyarylate resin calculated according to Hansen solubility parameters satisfy the following formulas (1) and (2), respectively, Formula (1) DIS HT is less than or equal to 3.9 Formula (2) is that DIS PC <12.0 is more than or equal to 9.2.
  2. 2. The electrophotographic photoreceptor according to claim 1, wherein, The vector distance DIS OHCT （J/cm 3 ） 1/2 between the HSP value of the phenol compound and the HSP value of the charge transport material calculated from hansen solubility parameters satisfies the following formula (3), Formula (3) is 3.6-DIS OHCT -7.0.
  3. 3. The electrophotographic photoreceptor according to claim 1 or 2, wherein, The vector distance DIS OHPA （J/cm 3 ） 1/2 between the HSP value of the phenol compound and the HSP value of the polyarylate resin calculated from hansen solubility parameters satisfies the following formula (4), Formula (4): DIS OHPA to 8.0.
  4. 4. The electrophotographic photoreceptor according to any of claim 1 to 3, wherein, The hydrogen bond term δh OH （J/cm 3 ） 1/2 of the phenol compound calculated from hansen solubility parameters satisfies the following formula (5), The delta H OH is more than or equal to 3.5 and less than or equal to 7.7.
  5. 5. The electrophotographic photoreceptor according to any of claims 1 to 4, wherein, The phenolic compound comprises a hindered phenolic compound.
  6. 6. The electrophotographic photoreceptor according to claim 5, wherein, The phenol compound contains a phenol compound having 3 or less phenol functional groups and a molecular weight of 300 or more.
  7. 7. The electrophotographic photoreceptor according to any of claims 1 to 6, wherein, The polyarylate resin has a dicarboxylic acid unit represented by the following formula (A) and a diol unit represented by the following formula (B), [ 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 divalent linking group, 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.
  8. 8. The electrophotographic photoreceptor according to any of claims 1 to 7, wherein, The polyarylate resin and the polycarbonate resin each have a structural unit comprising biphenyl represented by the following formula (BP), [ Chemical formula 2] In the formula (BP), j is an integer of 0 to 4, j R 1 are each independently methyl or ethyl, k is an integer of 0 to 4, and k R 2 are each independently methyl or ethyl.
  9. 9. A process cartridge provided with the electrophotographic photoreceptor as claimed in any one of claim 1 to 8, The process cartridge is attached to and detached from the image forming apparatus.
  10. 10. An image forming apparatus includes: the electrophotographic photoreceptor of any one of claims 1 to 8; 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 with a developer containing a toner to form a toner image, and And a transfer device for transferring the toner image to the surface of the recording medium.
  11. 11. The image forming apparatus according to claim 10, further comprising: And a cleaning device having a cleaning blade in contact with the surface of the electrophotographic photoreceptor and cleaning the surface of the electrophotographic photoreceptor.
  12. 12. The image forming apparatus according to claim 11, wherein, The contact portion of the cleaning blade with the electrophotographic photoreceptor is composed of a member containing a urethane rubber obtained by polymerizing at least a polyol component and a polyisocyanate component, and having a ratio M100/Re of 100% modulus M100 (MPa) to a modulus of resilience Re (%) of 0.25 or more, a modulus of resilience Re of less than 25%, and a tensile stress at 200% strain of 15MPa or more.
  13. 13. The image forming apparatus according to claim 12, wherein, The ratio M100/Re is 0.28 or more and 1.0 or less.

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 organic electrophotographic photoreceptor comprising a conductive substrate and a layered photosensitive layer having a charge generating layer and a charge transporting layer disposed on the conductive substrate, wherein the charge transporting layer contains a polyester resin and a polycarbonate resin each having a charge transporting material and a specific structural unit. Patent document 2 discloses an electrophotographic photoreceptor including a conductive substrate and a photosensitive layer, wherein the photosensitive layer contains at least a charge generating agent, a charge transporting agent, and a binder resin, the binder resin includes a polyarylate resin and a polycarbonate resin, the polyarylate resin and the polycarbonate resin have specific structural units, and a ratio (m PAR/（mPAR+mPC)) of a content m PAR of the polyarylate resin to a total amount of a content m PAR of the polyarylate resin and a content m PC of the polycarbonate resin is 0.10 or more and 0.90 or less. Patent document 1 Japanese patent application laid-open No. 2024-01918 Patent document 2 Japanese patent application laid-open No. 2017-211448 Disclosure of Invention The object of the present embodiment is to provide an electrophotographic photoreceptor in which image density unevenness is reduced as compared with a case where "the charge transport layer does not contain a phenol compound" or "the charge transport layer does not satisfy the formula (1) or (2)" in an electrophotographic photoreceptor provided with a conductive substrate, a charge generation layer, and a charge transport layer containing a charge transport material, a polyarylate resin, and a polycarbonate resin. Specific means for solving the above problems include the following means. The formulae are the same as those of the same numbers described below. <1> An electrophotographic photoreceptor comprising a conductive substrate, a charge generation layer disposed on the conductive substrate, and a charge transport layer disposed on the charge generation layer, The charge transport layer contains a phenol compound, a polyarylate resin, a polycarbonate resin, and a charge transport material, and the vector distance DIS HT（J/cm3）1/2 between the HSP value of the charge transport material and the HSP value of the polyarylate resin and the vector distance DIS PC（J/cm3）1/2 between the HSP value of the polycarbonate resin and the HSP value of the polyarylate resin calculated from hansen solubility parameters satisfy the following formulas (1) and (2), respectively. Formula (1) DIS HT is less than or equal to 3.9 Formula (2) DIS PC <12.0 with a value of 9.2 <2> The electrophotographic photoreceptor according to the <1>, wherein the vector distance DIS OHCT（J/cm3）1/2 between the HSP value of the phenol compound and the HSP value of the charge transporting material calculated according to hansen solubility parameters satisfies the following formula (3). Formula (3) DIS OHCT is 3.6-7.0 <3> The electrophotographic photoreceptor according to the <1> or <2>, wherein a vector distance DIS OHPA（J/cm3）1/2 between the HSP value of the phenol compound and the HSP value of the polyarylate resin calculated according to hansen solubility parameters satisfies the following formula (4). Formula (4) DIS OHPA -8.0 <4> The electrophotographic photoreceptor according to any one of the <1> to <3>, wherein the hydrogen bond term δh OH（J/cm3）1/2 of the phenol compound calculated according to hansen solubility parameters satisfies the following formula (5). The delta H OH is more than or equal to 3.5 and less than or equal to 7.7 <5> The electrophotographic photoreceptor according to any one of <1> to <4>, wherein the phenol compound comprises a hindered phenol compound. <6> The electrophotographic photoreceptor according to the <5>, wherein the phenol compound contains a phenol compound having 3 or less phenol functional groups and a molecular weight of 300 or more. <7> The electrophotographic photoreceptor according to any one of <1> to <6>, wherein the polyarylate resin has a dicarboxylic acid unit represented by the following formula (a) and a diol unit represented by the formula (B). [ 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 divalent 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