G03G5/0609

IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD

An image forming apparatus includes an image bearing member, a charger, a light exposure device, a development device, a transfer belt, a primary transfer device, a secondary transfer device, and a cleaning member. The cleaning member is pressed against a circumferential surface of the image bearing member and collects residual toner remaining on the circumferential surface of the image bearing member as a result of primary transfer of a toner. The transfer belt has a surface resistivity of at least 6 Log Ω and no greater than 11 Log Ω. A linear pressure of the cleaning member on the circumferential surface of the image bearing member is at least 10 N/m and no greater than 40 N/m. The image bearing member includes a conductive substrate and a photosensitive layer of a single layer. The image bearing member satisfies formula (1):

[00001] 0.60 V ( Q / S ) × ( d / .Math. r .Math. .Math. 0 ) ( 1 )

Electrophotographic photoreceptor, method for manufacturing same, and electrophotographic device

An electrophotographic photoreceptor, including a photosensitive layer formed on an electroconductive substrate. The photosensitive layer includes a charge-generating material and an electron-transporting material, and the electron-transporting material includes first and second electron-transporting materials. A difference in lowest unoccupied molecular orbital (LUMO) energy between the first electron-transporting material and the charge-generating material is in a range from 1.0 to 1.5 eV, and a difference in LUMO energy between the second electron-transporting material and the charge-generating material is in a range from 0.6 to 0.9 eV. A ratio of mass of the second electron-transporting material to a total of mass of the first electron-transporting material and the mass of the second electron-transporting material is in a range from 3 to 40%.

UNDERCOAT LAYER, METHOD FOR MANUFACTURING UNDERCOAT LAYER, ELECTROPHOTOGRAPHIC PHOTORECEPTOR, AND IMAGE FORMING APPARATUS
20210286277 · 2021-09-16 ·

The undercoat layer contains metal particles and a polyamide resin. The metal particle has a core and a coat layer covering at least a part of the core. The core contains titanium oxide. The coat layer contains at least a metal oxide different from titanium oxide. The metal oxide different from the titanium oxide is located on the outermost surface of the metal particles. The polyamide resin has an amide bond and an alkylene group. The absorption rate of the first peak derived from the amide bond to the second peak derived from the alkylene group to the first absorbance measured by infrared spectroscopy is ≥0.70.

ELECTROPHOTOGRAPHIC PHOTOCONDUCTOR, METHOD OF MANUFACTURING THE SAME, AND ELECTROPHOTOGRAPHIC DEVICE

Provided are an electrophotographic photoconductor being resistant to abrasion even in long-term use, having highly sensitive electric characteristics, being capable of maintaining a high retention rate, and being capable of providing a stable image without filming, a method of manufacturing the same, and an electrophotographic device. The photoconductor includes an electroconductive substrate (1), a charge generation layer (3), and a charge transport layer (4); the charge transport layer contains a hole transport material, a resin binder, an electron transport material, and an inorganic oxide; the charge generation layer contains a charge generation material; the masses of the hole transport material, the resin binder, the electron transport material, and the inorganic oxide in the charge transport layer respectively denoted by a to d satisfy 1.5≤b/a≤5.7, 0.005≤c/a≤0.35, 0.05≤d/a≤0.70, a≥c+d, and c/d≥0.01; the hole transport material contains a compound expressed by formula (A-1); and the charge generation material contains titanyl phthalocyanine having an exothermic peak at 251±5° C., a half-value width of the exothermic peak equal to or less than 15° C., and a heating value equal to or greater than 1.0 mJ/mg when a temperature rise condition is 20° C./min in differential scanning calorimetry, and having an X-ray diffraction peak at 27.2±0.3°.

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IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD
20210165337 · 2021-06-03 ·

An image forming apparatus in which no image smearing occurs even under high-temperature and high-humidity conditions while durability and low-temperature fixability are maintained. The image forming apparatus comprises: an electrophotographic photosensitive member comprising a support and a photosensitive layer formed on the support; an image forming unit configured to form an electrostatic image on the electrophotographic photosensitive member; a developing unit comprising a toner and configured to supply the toner to the electrostatic image formed on the electrophotographic photosensitive member for forming a toner image; and a transferring unit configured to transfer the toner image from the electrophotographic photosensitive member, wherein a surface layer of the electrophotographic photosensitive member is a surface layer comprises a binder resin (A), the toner is a toner including toner particles each containing a binder resin (B) and a wax, and the binder resin (A) has a specific structure I.

Electrophotographic photosensitive member, process cartridge, and image forming apparatus

An electrophotographic photosensitive member includes a conductive substrate and a photosensitive layer. The photosensitive layer is a single layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The hole transport material includes a compound represented by chemical formula (1-1) or (1-2). The photosensitive layer further contains an n-type pigment. The n-type pigment is preferably an azo pigment or a perylene pigment. ##STR00001##

Electrophotographic photosensitive member, process cartridge, and image forming apparatus

A photosensitive layer included in an electrophotographic photosensitive member contains at least a charge generating material, a hole transport material, and a binder resin. The hole transport material includes a compound (1). The binder resin includes a polyarylate resin having at least one repeating unit (10) and at least one repeating unit (11). Alternatively, the binder resin includes a polycarbonate resin having a repeating unit (20) and a repeating unit (21). The general formulas (1), (10), (11), (20), and (21) are as follows ##STR00001##

Electrophotographic photoconductor, process cartridge, and image forming apparatus

An electrophotographic photoconductor includes: a conductive substrate; and a single-layer-type photoconductive layer that is provided on the conductive substrate, contains a binder resin, a charge generating material, a hole transporting material, and an electron transporting material, and has an index A represented by the following equation (1) in a range of 7.98 or more and 7.28 or less, Equation (1): A=(0.057M)(0.002F)(0.252), in which, in the equation (1), M represents a Martens hardness of the single-layer-type photoconductive layer, F represents a Young's modulus of the single-layer-type photoconductive layer, and represents an elastic deformation ratio of the single-layer-type photoconductive layer.

ELECTROPHOTOGRAPHIC PHOTOCONDUCTOR, METHOD OF MANUFACTURING THE SAME, AND ELECTROPHOTOGRAPHIC DEVICE INCLUDING THE SAME

An electrophotographic photoconductor includes a conductive substrate; and a photosensitive layer provided on the conductive substrate and containing a charge generation material, a hole transport material, a first electron transport material, from 3% by mass to 40% by mass of a second electron transport material, a resin binder, and an inorganic oxide filler surface-treated with a silane coupling agent. In a dipole-dipole force component (a Hansen solubility parameter), the first electron transport material and the silane coupling agent have a difference of SPa<2.50; the second electron transport material and the silane coupling agent have a difference of SPb<2.50; and the first electron transport material and the second electron transport material have a difference of 0.30<SPc<1.00. In a London dispersion force component (a Hansen solubility parameter), the resin binder and the silane coupling agent have a difference of SPd<2.00.

Image forming apparatus and image forming method

In an image forming apparatus, a cleaning member is pressed against a circumferential surface of an image bearing member and collects a toner remaining on the circumferential surface of the image bearing member. The toner has a number average roundness of 0.965 to 0.998. The toner has a D.sub.50 of 4.0 m to 7.0 m. A linear pressure of the cleaning member on the circumferential surface of the image bearing member is 10 N/m to 40 N/m. The image bearing member includes a single-layer photosensitive layer containing a charge generating material and a hole transport material. Ionization potential Ip.sub.HTM of the hole transport material and ionization potential Ip.sub.CGM of the charge generating material satisfy mathematical formula (1) Ip.sub.HTM5.30 eV, mathematical formula (2) Ip.sub.CGM5.30 eV, and mathematical formula (3) 0.09 eV|Ip.sub.HTMIp.sub.CGM|0.30 eV.