Patent classifications
G03G5/061473
IMAGE FORMING APPARATUS AND IMAGE FORMING METHOD
An image forming apparatus includes an image bearing member, a charger, and a cleaning member. The charger charges a circumferential surface of the image bearing member to a positive polarity. The cleaning member is pressed against the circumferential surface of the image bearing member and collects a toner remaining on the circumferential surface of the image bearing member. A linear pressure N of the cleaning member on the circumferential surface of the image bearing member is at least 14 N/m and no greater than 40 N/m. A rebound resilience R of the cleaning member at a temperature of 25 C. is at least 38%. The leaner pressure N and the rebound resilience R satisfy mathematical formula (1A). The image bearing member satisfies mathematical formula (1B)
Method of producing an electrophotographic photoreceptor
A method of producing an electrophotographic photoreceptor composed of a photosensitive layer provided on a conductive substrate, includes, in the formation of an outermost layer, controlling slope k of a straight line obtained by plotting the average film density of outermost layer and boiling point of solvent used for the formation of the outermost layer along the ordinate and the abscissa, respectively, to be 1.50E-4 (g/cm.sup.3.Math. C.) or greater, and adjusting the difference in film density of the outermost layer between the surface side and the side close to the conductive substrate to be 0.030 g/cm.sup.3 or less. The electrophotographic photoreceptor has reduced image defects even after long-term use and has excellent wear performance.
ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER AND IMAGE FORMING APPARATUS
An electrophotographic photosensitive member (1) includes a conductive substrate (2) and a photosensitive layer (3) disposed directly or indirectly on the conductive substrate (2). The photosensitive layer (3) has a charge generating layer (3a) and a charge transport layer (3b) disposed in order from the conductive substrate (2). The charge generating layer (3a) contains a charge generating material. The charge transport layer (3b) contains a charge transport material, a binder resin, and a pigment that absorbs light having an irradiation wavelength. The binder resin includes a polyarylate resin including a repeating unit represented by general formula (1):
##STR00001##
In general formula (1), 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):
##STR00002##
The pigment is a naphthalocyanine compound represented by general formula (2) or (3):
##STR00003##
PHOTOSENSITIVE BODY FOR ELECTROPHOTOGRAPHY, METHOD FOR PRODUCING THE SAME, AND ELECTROPHOTOGRAPHIC DEVICE INCLUDING THE SAME
The present invention provides an electrophotographic photoreceptor including a photosensitive layer containing an electron transport material, and having high pressure resistance and suppressed occurrence of a leak phenomenon, a method for producing the same, and an electrophotographic device using the same. The electrophotographic photoreceptor includes an electrically conductive support containing an aluminum alloy; an anodic oxide film formed on a surface of the electrically conductive support; and a photosensitive layer formed on the anodic oxide film. The photosensitive layer contains an electron transport material having an electron mobility of 10.sup.7 cm.sup.2/V/sec or more when field intensity is set to 20 V/m. The surface of the electrically conductive support having the anodic oxide film formed thereon has an admittance value that is 25 S or more and 60 S or less.
POSITIVE CHARGING ELECTROPHOTOGRAPHIC PHOTORECEPTOR, ELECTROPHOTOGRAPHIC CARTRIDGE AND IMAGE FORMING APPARATUS
The object of the present invention is to provide a positive charging electrophotographic photoreceptor having high sensitivity, low residual potential, and excellent chargeability, and relates to a positive charging electrophotographic photoreceptor including a conductive support, a photosensitive layer, and a protective layer in this order, the photosensitive layer containing a charge generation substance, a positive hole transport substance, and an electron transport substance in the same layer, in which the positive hole transport substance includes at least one of the compounds represented by any one of the following formulas (1) to (5), and a binder resin of the protective layer is an alcohol-soluble thermoplastic resin, providing that the symbols in the formula are defined in the specification.
##STR00001##
BIS-BUTADIENE DERIVATIVE AND ELECTROPHOTOGRAPHIC PHOTOSENSITIVE MEMBER
A bis-butadiene derivative is represented by general formula (1) shown below.
##STR00001##
In general formula (1), Ra, Rb, and Rc each represent, independently of one another, an alkyl group having a carbon number of at least 1 and no greater than 8 or an alkoxy group having a carbon number of at least 1 and no greater than 8. l and m each represent, independently of one another, an integer of at least 0 and no greater than 5. n represents an integer of at least 0 and no greater than 4. Chemical groups Ra may be the same as or different from each other. Chemical groups Rb may be the same as or different from each other. Chemical groups Rc may be the same as or different from each other.
Polyarylate resin and electrophotographic photosensitive member
A polyarylate resin is represented by general formula (1) shown below. In general formula (1), R.sup.1 represents a hydrogen atom or methyl group. R.sup.2 and R.sup.3 each represent a hydrogen atom or an alkyl group having a carbon number of at least 1 and no greater than 4. R.sup.2 and R.sup.3 are not the same as one another. When R.sup.1 represents a hydrogen atom, R.sup.2 and R.sup.3 are not bonded to one another. When R.sup.1 represents a methyl group, R.sup.2 and R.sup.3 are optionally bonded to one another to form a ring. r and s each represent a number greater than or equal to 0 and less than or equal to 49. t and u each represent a number greater than or equal to 1 and less than or equal to 50. r+s+t+u=100. r+t=s+u. ##STR00001##
IMAGE FORMING APPARATUS AND PROCESS CARTRIDGE
An image forming apparatus includes an electrophotographic photoreceptor that has a photosensitive layer constituting a surface of the electrophotographic photoreceptor, a charging device that charges the surface of the electrophotographic photoreceptor, an electrostatic charge image forming device that forms an electrostatic charge image on the charged surface of the electrophotographic photoreceptor, a developing device that accommodates a developer containing a toner which contains toner particles and an external additive, and develops the electrostatic charge image formed on the surface of the electrophotographic photoreceptor by the developer as a toner image, a transfer device that transfers the toner image formed on the surface of the electrophotographic photoreceptor to a surface of a recording medium, and a cleaning device that includes a cleaning blade coming into contact with the surface of the electrophotographic photoreceptor and cleaning at least residual toner particles on the surface of the electrophotographic photoreceptor
ELECTROPHOTOGRAPHIC PHOTORECEPTOR, PROCESS CARTRIDGE, AND IMAGE FORMING APPARATUS
An electrophotographic photoreceptor includes a conductive substrate, and a lamination type photosensitive layer disposed on the conductive substrate and including a charge generation layer and a charge transport layer, in which the charge transport layer contains a charge transport material, at least one of a polyester resin (PEz) or a polycarbonate resin (PCz) that has at least one of a structure (Z1) represented by Formula (Z1) or a structure (Z2) represented by Formula (Z2) at at least one terminal, and a resin (X) that has at least one of a unit (X1) represented by Formula (X1) or a unit (X2) represented by Formula (X2), a mass proportion of the resin (X) in a total amount of the polyester resin (PEz), the polycarbonate resin (PCz), and the resin (X) in the charge transport layer is 0.5% by mass or greater and 30% by mass or less, and the charge transport layer has an average thickness of greater than 30 ?m and less than 50 ?m,
##STR00001## in Formula (Z1), Ar.sup.1 represents an aromatic ring that may have a substituent, in Formula (Z2), Ar.sup.2 represents an aromatic ring that may have a substituent,
##STR00002## in Formula (X1), R.sup.101, R.sup.102, and R.sup.103 each independently represent a hydrogen atom or an alkyl group having 1 or more and 5 or less carbon atoms, L.sup.101 represents a single bond, an alkylene group having 1 or more and 5 or less carbon atoms, O, C(?O), C(?O)O, an aromatic ring that may have a substituent, or a combination thereof, L.sup.102 represents a single bond, an alkylene group having 1 or more and 5 or less carbon atoms, O, C(?O), C(?O)O, or a combination thereof, R.sup.104 and R.sup.105 each independently represent an alkyl group having 1 or more and 5 or less carbon atoms, n represents an integer of 0 or greater and 300 or less, R.sup.106, R.sup.107, and R.sup.108 each independently represent an alkyl group having 1 or more and 5 or less carbon atoms or O[Si(R.sup.109)(R.sup.110)O].sub.mSi(R.sup.111)(R.sup.112)(R.sup.113), R.sup.109, R.sup.110, R.sup.111, R.sup.12, and R.sup.113 each independently represent an alkyl group having 1 or more and 5 or less carbon atoms, and m represents an integer of 0 or greater and 20 or less, in Formula (X2), R.sup.201, R.sup.202, and R.sup.203 each independently represent a hydrogen atom or an alkyl group having 1 or more and 5 or less carbon atoms, L.sup.201 represents a single bond, an alkylene group having 1 or more and 5 or less carbon atoms, O, C(?O), C(?O)O, an aromatic ring that may have a substituent, or a combination thereof, L.sup.202 represents a single bond, an alkylene group having 1 or more and 5 or less carbon atoms, O, C(?O), C(?O)O, or a combination ther
Image forming apparatus and process cartridge
An image forming apparatus includes an electrophotographic photoreceptor that has a photosensitive layer constituting a surface of the electrophotographic photoreceptor, a charging device that charges the surface of the electrophotographic photoreceptor, an electrostatic charge image forming device that forms an electrostatic charge image on the charged surface of the electrophotographic photoreceptor, a developing device that accommodates a developer containing a toner which contains toner particles and an external additive, and develops the electrostatic charge image formed on the surface of the electrophotographic photoreceptor by the developer as a toner image, a transfer device that transfers the toner image formed on the surface of the electrophotographic photoreceptor to a surface of a recording medium, and a cleaning device that includes a cleaning blade coming into contact with the surface of the electrophotographic photoreceptor and cleaning at least residual toner particles on the surface of the electrophotographic photoreceptor.