CN-122018265-A - Electrophotographic photoreceptor, process cartridge, and image forming apparatus

CN122018265ACN 122018265 ACN122018265 ACN 122018265ACN-122018265-A

Abstract

An electrophotographic photoreceptor, a process cartridge, and an image forming apparatus, wherein the electrophotographic photoreceptor comprises a conductive substrate, and a photosensitive layer disposed on the conductive substrate, wherein the outermost layer contains a charge transport material, and the polyarylate resin and the polycarbonate resin have a weight average molecular weight MwA of-14 x (MwA-MwB)/MwA of 14 x (MwA-100) or less, wherein the polyarylate resin comprises at least one dicarboxylic acid unit selected from the group consisting of a dicarboxylic acid unit (A2) represented by the following formula (A2), a dicarboxylic acid unit (A3) represented by the following formula (A3), a dicarboxylic acid unit (A4) represented by the formula (A4), and a dicarboxylic acid unit (A5) represented by the formula (A5), and a diol unit represented by the formula (B). [ chemical formula 1] formula (A2) Equation (A3) Formula (A4) Equation (A5) [ Chemical formula 2] formula (B)

Inventors

Okazaki Youdu
IDE KENTA
NARITA KOSUKE
SASAKI TOMOYA
Kusano Kawoo
FUJII RYOUSUKE
IWASAKI MASAHIRO
Kiko Youchi
KANO FUYUKI
OYAMADA YUKI
GAO YANGPING

Assignees

富士胶片商业创新有限公司

Dates

Publication Date: 20260512
Application Date: 20250507
Priority Date: 20241111

Claims (9)

1. An electrophotographic photoreceptor comprising: Conductive matrix, and A photosensitive layer disposed on the conductive substrate, The outermost layer contains a charge transport material, a polyarylate resin and a polycarbonate resin each having at least one dicarboxylic acid unit selected from the group consisting of a dicarboxylic acid unit (A2) represented by the following formula (A2), a dicarboxylic acid unit (A3) represented by the following formula (A3), a dicarboxylic acid unit (A4) represented by the following formula (A4) and a dicarboxylic acid unit (A5) represented by the following formula (A5), and a diol unit represented by the following formula (B), The weight average molecular weight MwA of the polyarylate resin and the weight average molecular weight MwB of the polycarbonate resin satisfy-14 to 100× (MwA-MwB)/MwA to 14, [ Chemical formula 1] [ Chemical formula 2] 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; 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. The electrophotographic photoreceptor according to claim 1, wherein, The weight average molecular weight MwA of the polyarylate resin and the weight average molecular weight MwB of the polycarbonate resin satisfy-8 to 100× (MwA-MwB)/MwA to 8.
3. The electrophotographic photoreceptor according to claim 1 or 2, wherein, The weight average molecular weight MwA of the polyarylate resin is 7 ten thousand or more and 14 ten thousand or less.
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. The electrophotographic photoreceptor according to any of claims 1 to 4, wherein, The polyarylate resin and the polycarbonate resin each have a structural unit comprising biphenyl represented by the following formula (BP), [ Chemical formula 5] 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.
6. The electrophotographic photoreceptor according to any of claims 1 to 5, wherein, The ratio of the polyarylate resin to the total amount of the polyarylate resin and the polycarbonate resin contained in the outermost layer is 25 mass% or more and 75 mass% or less.
7. The electrophotographic photoreceptor according to any of claims 1 to 6, wherein, The photosensitive layer is provided with a charge generation layer and a charge transmission layer, and the charge transmission layer is the surface-most layer.
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. 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 in which a surface layer contains a polyarylate having a viscosity average molecular weight (Ma) of 30000 to 105000, a polycarbonate having a viscosity average molecular weight (Mc) of 25000 to 55000, and Ma > Mc, a polycarbonate, a silicone copolycarbonate, and a graft polymer containing a polymerizable monomer having a silicon atom in a side chain as a constituent component. Patent document 2 discloses a photoreceptor containing at least one of a polyester resin having a structural unit having an aromatic ring and a polycarbonate resin having a structural unit having an aromatic ring in a charge transport layer. Patent document 3 discloses an electrophotographic photoreceptor in which a charge transport layer contains a charge transport material, a polyester resin having a predetermined aromatic structure, and a polycarbonate resin. Patent document 1 Japanese patent laid-open No. 2002-107965 Patent document 2 Japanese patent application laid-open No. 2023-121553 Patent document 3 Japanese patent application laid-open No. 2024-01918 Disclosure of Invention The invention provides an electrophotographic photoreceptor which maintains cleanliness to the end of life and has a surface layer which is not easily peeled off. 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: Conductive matrix, and A photosensitive layer disposed on the conductive substrate, The outermost layer contains a charge transport material, a polyarylate resin and a polycarbonate resin having at least one dicarboxylic acid unit selected from the group consisting of 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), and a diol unit represented by the formula (B), The weight average molecular weight MwA of the polyarylate resin and the weight average molecular weight MwB of the polycarbonate resin satisfy-14 to be less than or equal to 100× (MwA-MwB)/MwA to be less than or equal to 14. <2> The electrophotographic photoreceptor according to <1>, wherein, The weight average molecular weight MwA of the polyarylate resin and the weight average molecular weight MwB of the polycarbonate resin satisfy-8 to 100× (MwA-MwB)/MwA to 8. <3> The electrophotographic photoreceptor according to <1> or <2>, wherein, The weight average molecular weight MwA of the polyarylate resin is 7 ten thousand or more and 14 ten thousand or less. <4> The electrophotographic photoreceptor according to any of <1> to <3>, wherein, The diol unit represented by the formula (B) includes at least one selected from the group consisting of a diol unit (B1) represented by the 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). <5> The electrophotographic photoreceptor according to any of <1> to <4>, wherein, The polyarylate resin and the polycarbonate resin each have a structural unit comprising biphenyl represented by formula (BP). <6> The electrophotographic photoreceptor according to any of <1> to <5>, wherein, The ratio of the polyarylate resin to the total amount of the polyarylate resin and the polycarbonate resin contained in the outermost layer is 25 mass% or more and 75 mass% or less. <7> The electrophotographic photoreceptor according to any of <1> to <6>, wherein, The photosensitive layer is provided with a charge generation layer and a charge transmission layer, and the charge transmission layer is the surface-most layer. <8> A process cartridge comprising an electrophotographic photoreceptor according to any one of <1> to <7>, The process cartridge is attached to and detached from the image forming apparatus. <9> An image forming apparatus includes: The electrophotographic photoreceptor of any one of <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