G03G5/061443

POLYARYLATE RESIN AND ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER

An electrophotographic photosensitive member includes a photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, and a binder resin. The binder resin contains a polyarylate resin represented by general formula (1). In general formula (1), r and s each represent an integer of at least 0 and no greater than 49 and t and u represents an integer of at least 1 and no greater than 50. Furthermore, r+s+t+u=100 and r+t=s+u. X and Y each represent, independently of one another, a divalent group represented by chemical formula (1-1), (1-2), (1-3), or (1-4).

##STR00001##

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 photosensitive layer. The photosensitive layer contains a charge generating material, a hole transport material, an electron transport material, and a binder resin. The binder resin contains a polyarylate resin. The polyatylate resin is represented by general formula (1). The hole transport material contains a compound represented by general formula (HTM1), (HTM2), (HTM3), (HTM4), (HTM5), (HTM6), or (HTM7). The photosensitive layer has a scratch resistance depth of no greater than 0.50 m. The photosensitive layer has a Vickers hardness of at least 17.0 HV.

##STR00001## ##STR00002##

Electrophotographic photoreceptor and image forming apparatus
09880477 · 2018-01-30 · ·

The invention provides an image forming apparatus and an electrophotographic photoreceptor, comprising: a conductive support; and at least a charge generation layer and a charge transport layer on the conductive support, wherein said charge generation layer contains a hydroxygallium phthalocyanine synthesized using a halogen solvent, said charge transport layer contains a polyester resin having a specific structural unit, and said charge transport layer is formed using a non-halogen solvent.

Electrophotographic photoreceptor and image formation device
09874824 · 2018-01-23 · ·

An electrophotographic photoreceptor comprising at least a photosensitive layer on a conductive substrate, wherein the photosensitive layer is a laminate having a charge transport layer and a charge generation layer, the charge transport layer contains four or more types of compounds each having a maximum absorption wavelength falling within a wavelength range of from 300 nm to 600 nm in a tetrahydrofuran solution at 25? C., and maximum absorption wavelengths falling within the wavelength range of at least four types of the compounds of said four or more types of the compounds are separated from each other by 10 nm or more.

Electrophotographic photoreceptor, process cartridge, image forming apparatus, and conductive substrate that may be included in electrophotographic photoreceptor
09846378 · 2017-12-19 · ·

An electrophotographic photoreceptor includes a conductive substrate including an outer peripheral surface treated with a silazane; and a photosensitive layer on the outer peripheral surface of the conductive substrate. The photosensitive layer includes a charge generating material and a charge transporting material.

Benzidine derivative, method for producing benzidine derivative, and electrophotographic photosensitive member
09817325 · 2017-11-14 · ·

A benzidine derivative is represented by general formula (1). In the general formula (1), R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9, and R.sub.10 each represent, independently of one another, a hydrogen atom, a halogen atom, an optionally substituted alkyl group having a carbon number of at least 1 and no greater than 6, an optionally substituted alkoxy group having a carbon number of at least 1 and no greater than 6, or an optionally substituted aryl group having a carbon number of at least 6 and no greater than 14. n represents an integer of at least 0 and no greater than 2. ##STR00001##

Image forming method, process cartridge, and electrophotographic apparatus

An image forming method in which a surface layer of an electrophotographic photosensitive member contains a compound having a specific structure in an amount of 0.1% to 10% by mass based on the total mass of the surface layer, and in a charged region of the surface of the electrophotographic photosensitive member charged in a charging step, a non-image forming region in which an electrostatic latent image is not formed is not irradiated with destaticizing light or is irradiated with reduced destaticizing light.

Electrophotographic photoreceptor, electrophotographic apparatus comprising the same, and package of electrophotographic photoreceptor

In a negatively-chargeable laminate-type electrophotographic photoreceptor, a charge generation layer and another charge transport layer are arranged on a conductive substrate directly or via an intermediate layer. The charge transport layer contains at least a hole-transporting substance, an electron-transporting substance and a binder resin; the mass ratio (R.sub.PN) [% by mass] between mass (P) of the hole-transporting substance and mass (N) of the electron-transporting substance is represented by the following equation (1), and satisfies the following equation (2):
R.sub.PN=(N/(P+N))100(1)
1R.sub.PN40(2); and
when a voltage of +6 kV is applied to the photoreceptor for 5 seconds via a resin sheet having a thickness of 50 m and a surface resistivity of 210.sup.7 /cm.sup.2, the surface potential difference (Vo) and half-tone potential difference (Vh) between before and after the voltage application are both 15 V or less.

COMPOUND, ELECTROPHOTOGRAPHIC PHOTORECEPTOR, AND PROCESS CARTRIDGE
20170277049 · 2017-09-28 · ·

A compound has a structure represented by the following formula (C1):

##STR00001## wherein R.sub.a1, R.sub.a2, R.sub.a3, R.sub.a41, R.sub.a42, R.sub.a43, R.sub.a44, R.sub.a45, R.sub.a5, R.sub.a6, R.sub.a7, R.sub.a8, R.sub.a9, R.sub.a10, and R.sub.a11 each independently represent a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an aralkyl group, an aryl group, a cyano group, a halogen atom, or a group obtained by combining two or more of the above groups, and a combination of R.sub.a1 and R.sub.a2, R.sub.a41 and R.sub.a42, R.sub.a42 and R.sub.a43, R.sub.a43 and R.sub.a44, R.sub.a44 and R.sub.a45, R.sub.a5 and R.sub.a6, R.sub.a8 and R.sub.a9, or R.sub.a10 and R.sub.a11 each independently may form a ring.

IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD
20170255113 · 2017-09-07 · ·

An image forming apparatus includes an electrophotographic photoreceptor that includes a photosensitive layer that contains a charge generation material, a charge transport material, and a binder resin; a charging unit; an electrostatic latent image forming unit; a developing unit; and a transfer unit. A charge amount Q(C/m.sup.2), which is accumulated in the photosensitive layer by exposure conducted by using the electrostatic latent image forming unit, per unit area of a surface of the electrophotographic photoreceptor, a charge potential VH(V) after the surface of the electrophotographic photoreceptor is charged by using the charging unit, and an exposure potential VL(V) of a portion of the surface of the electrophotographic photoreceptor exposed by using the electrostatic latent image forming unit satisfy the following formula: 20(V.Math.m.sup.2/C)[VHVL](V)/Q(C/m.sup.2)60(V.Math.m.sup.2/C)