JP2012042880A - Developing roller, electrophotographic process cartridge and electrophotographic image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a developing roller that hardly causes peeling of a surface layer even when image formation at a high speed is repeated.SOLUTION: The developing roller comprises a shaft core body, and an elastic layer, an intermediate layer and a surface layer, layered in this order on a circumference of the shaft core body. The surface layer contains organosiloxane; and in the organosiloxane, an abundance ratio (O/Si) of oxygen atoms that form chemical bonds with silicon atoms to silicon atoms is 0.65 or more and 1.95 or less, and an abundance ratio (C/Si) of carbon atoms that form chemical bonds with silicon atoms to silicon atoms is 0.05 or more and 1.65 or less. The elastic layer has a compound elastic modulus (Ere) of 0.5 MPa or more and 20 MPa or less, while the intermediate layer has a compound elastic modulus (Erm) larger than the compound elastic modulus (Ere) of the elastic layer.

Description

  The present invention relates to a developing roller, an electrophotographic process cartridge, and an electrophotographic image forming apparatus.

  Patent Document 1 has an axial core body, an elastic layer, and a surface layer in this order, and the abundance ratio (O / Si) of oxygen atoms with which the surface layer forms a chemical bond with silicon atoms to silicon atoms is 0. .65 or more and 1.95 or less. And the developing roller containing the silicon oxide film whose abundance ratio (C / Si) of the carbon atom which forms the chemical bond with the silicon atom with respect to the silicon atom is 0.05 or more and 1.65 or less is disclosed. The silicon oxide film can effectively suppress the seepage of low molecular weight components from the elastic layer, has a surface excellent in toner releasability, has sufficient flexibility, and is formed by repeated image formation. Also exhibits the property of not easily causing cracks, and is excellent as a surface layer of a developing roller.

Japanese Patent No. 4165901

  However, the developing roller described in Patent Document 1 may peel off between the surface layer and the elastic layer when image output is repeated in a recent high-speed process speed electrophotographic image forming apparatus.

An object of the present invention is to provide a developing roller that has a surface layer that satisfies the following conditions (1) to (3) at a high level and that does not easily peel off even when high-speed image formation is repeated. Is to provide:
(1) Suppressing exudation of low molecular weight components from the elastic layer (2) Having a surface excellent in toner releasability (3) Showing excellent flexibility and sufficiently following deformation of the elastic layer .

The developing roller according to the present invention is a developing roller having a shaft body, and a laminated body provided around the shaft core body in which an elastic layer, an intermediate layer, and a surface layer are laminated in this order,
The surface layer contains an organosiloxane, and the organosiloxane has an abundance ratio (O / Si) of oxygen atoms to silicon atoms forming chemical bonds with silicon atoms of 0.65 or more and 1.95 or less. Abundance ratio (C / Si) of carbon atoms forming a chemical bond with silicon atoms to silicon atoms is 0.05 or more and 1.65 or less,
The elastic layer has a composite elastic modulus (Ere) of 0.5 MPa or more and 20 Mpa or less,
The intermediate layer is characterized in that the composite elastic modulus (Erm) is larger than the composite elastic modulus Ere of the elastic layer.

An electrophotographic process cartridge according to the present invention is an electrophotographic process cartridge that is detachably attached to an electrophotographic image forming apparatus main body,
The electrophotographic process cartridge includes at least a developing roller, a toner regulating member, and a toner container, and the developing roller is the developing roller.

  The electrophotographic image forming apparatus according to the present invention is an electrophotographic image forming apparatus having a photosensitive member and a developing roller disposed in contact with the photosensitive member, wherein the developing roller is the developing roller. Features.

  In the developing roller of the present invention, the surface layer is not easily peeled even by repeated use under high-speed output, has excellent durability, and can stably obtain a high-quality electrophotographic image over a long period of time.

It is a schematic block diagram which shows an example of the manufacturing apparatus of the developing roller of this invention. It is a schematic side view which shows an example of the manufacturing apparatus of the developing roller of this invention. It is a side view which shows an example of the developing roller of this invention. 1 is a schematic configuration diagram illustrating an example of an electrophotographic process cartridge of the present invention. 1 is a schematic configuration diagram illustrating an example of an electrophotographic image forming apparatus of the present invention.

The developing roller of the present invention includes a shaft core body and a laminated body in which an elastic layer, an intermediate layer, and a surface layer are stacked in this order, provided around the shaft core body.
[Shaft core]
The shaft core used in the developing roller of the present invention may have any strength necessary for the developing roller and conductivity that can serve as an electrode capable of moving the charged toner to the photosensitive member.

[Elastic layer]
The elastic layer is a layer constituting a laminated body provided around the shaft core body, is located on the shaft core body side, and has a composite elastic modulus (Ere) of 0.5 MPa or more and 20 MPa or less. When the elastic layer has a composite elastic modulus in the above range, together with the upper intermediate layer having a higher composite elastic modulus, the developing roller becomes a contact member such as a photoreceptor or a toner regulating member due to the non-use of the apparatus. Even if they are in contact with each other for a long time, it is possible to suppress the occurrence of pressure contact permanent distortion at the contact portion.

  In addition, by having the above-mentioned composite elastic modulus, the pressure applied to the toner passing between the contact member and the developing roller is relieved, and filming due to surface layer peeling and toner deterioration due to long-term use is effective at high speed. Can be suppressed.

  If the composite elastic modulus (Ere) of the elastic layer is 0.5 MPa or more, it is possible to suppress the occurrence of pressure contact permanent distortion at the contact portion of the developing roller, and the amount of deformation in contact with the toner regulating member increases. And the occurrence of image defects such as image streaks can be suppressed. In addition, when the pressure is 20 MPa or less, an excessive increase in stress due to the contact member can be suppressed, and in particular, occurrence of filming due to peeling of the surface layer or toner deterioration under high-speed image output can be suppressed.

  Here, the composite elastic modulus is obtained from a load-displacement curve when a specific indenter is pushed into the measurement sample. As the indenter, a Barkovic diamond indenter can be suitably used, and the elastic modulus can be measured in a measurement area of several hundred nm to several mm depending on the size of the indenter and the control accuracy of the apparatus. A measurement sample is prepared by embedding a small piece of a cut sample in a resin, then freezing it with a cryotramicrotome, and performing ultra-precise cutting to produce a measurement sample.

  The cross section of this sample is measured by single indentation in the indentation depth range of 200 nm to 250 nm using a nano intender (product name: TriboIndenter, manufactured by Hystron). The measurement is performed three times to obtain the arithmetic average value Es, and the composite elastic modulus (Er) is obtained from the following formula. When the measurement sample contains fine particles or the like, the matrix portion is measured.

Er = [(1-νs ² / Es + (1-νi ² ) / Ei) −1
Here, vs is the Poisson ratio of the sample, vi is the Poisson ratio of the indenter, Ei is the elasticity of the indenter, and ν i = 0.07 and E i = 1141 GPa are given for the Barkovic diamond indenter. Although the Poisson's ratio varies depending on the material, νs = 0.18 can be used as the Poisson's ratio of the elastic layer.

  The elastic layer can be molded using rubber or resin as a raw material main component, and may be either a foam or a non-foam. Various rubbers can be used as the raw material rubber, which can be appropriately selected to have a composite elastic modulus in the above range. Specific examples include the following.

  Ethylene-propylene-diene copolymer rubber (EPDM), acrylonitrile-butadiene rubber (NBR), chloroprene rubber (CR), natural rubber (NR), isoprene rubber (IR), styrene-butadiene rubber (SBR), fluorine rubber, silicone Rubber. Epichlorohydrin rubber, NBR hydride, polysulfide rubber, urethane rubber.

  Moreover, as a resin of a raw material main component, it is a thermoplastic resin mainly and the following are mentioned. Polyethylene resins such as low density polyethylene (LDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), and ethylene-vinyl acetate copolymer resin (EVA). Polypropylene resin, polycarbonate resin, polystyrene resin, ABS resin, polyimide. Polyester resins such as polyethylene terephthalate and polybutylene terephthalate. Fluorine resin. Polyamide resins such as polyamide 6, polyamide 66 and MXD6.

  These rubbers and resins may be used alone or in admixture of two or more. Of these, it is preferable to use silicone rubber because it exhibits weather resistance, chemical inertness, and excellent compression set properties.

  For the elastic layer, components such as a conductive agent and a non-conductive filler necessary for the required function, and various additive components used when forming rubber and resin moldings, for example, a crosslinking agent It is preferable that a catalyst and a dispersion accelerator are appropriately blended in the main rubber material.

  As the conductive agent, there are an ion conductive material based on an ion conductive mechanism and a conductivity imparting agent based on an electronic conductive mechanism, and either one or a combination thereof can be used. In particular, a carbon black-based conductive agent is suitable because it can be obtained relatively inexpensively and easily, and good conductivity can be imparted regardless of the types of the main rubber and resin material. As a means to disperse the fine powdered conductive agent in the main component rubber and resin material, a method using a kneader such as a roll kneader or a Banbury mixer is selected according to the main component rubber and resin material. do it.

The addition amount of the conductive agent is preferably in a range where the volume resistivity of the elastic layer is in the range of 1 × 10 ³ to 1 × 10 ¹¹ Ω · cm, and more preferably in the range of 1 × 10 ³ to 1 ×. 10 ⁸ Ω · cm. When the volume resistivity of the elastic layer is 1 × 10 ³ to 1 × 10 ¹¹ Ω · cm, the toner can be uniformly charged.

  In practice, the thickness of the elastic layer is preferably determined as appropriate in accordance with its hardness in order to achieve the target nip width. Specifically, it is preferably 0.5 mm or more, more preferably 1.0 mm or more. If the thickness of the elastic layer is 0.5 mm or more, it comes into contact with the photosensitive member to ensure a nip width, and in addition, satisfies a suitable setting property.

  The upper limit of the thickness of the elastic layer is not particularly limited as long as the accuracy of the outer diameter of the developing roller to be produced is not impaired, but is suitably 6.0 mm or less, and more preferably 5.0 mm or less. If the thickness of the elastic layer is 6.0 mm or less, even if the developing roller is placed in contact with the contact member for a long period of time, deformation distortion at the contact portion can be suppressed.

  The elastic layer can be formed by extrusion molding, compression molding, injection molding, or the like. Further, the layer configuration of the elastic layer is not limited to a single layer, and a configuration having two or more layers may be employed. When composed of two or more elastic layers, the composite elastic modulus (Ere) is the measured value of the thickest layer.

[Middle layer]
The intermediate layer is a layer constituting the laminate, and is positioned between the elastic layer and the surface layer, and shows a relationship of Ere <Erm when the composite elastic modulus is Erm. Such an intermediate layer functions as a buffer layer between the surface layer and the elastic layer, and suppresses delamination and toner deterioration against repeated image output under high-speed output in the electrophotographic image forming apparatus, and also a contact member. The image defect resulting from the deformation | transformation by long-term contact with is suppressed.

  The intermediate layer has a hardness capable of suppressing the compression set generated at the contact portion with the toner regulating member, but is low in flexibility to relieve stress between the surface layer and the contact member, and to suppress filming due to toner deterioration. It has a function to relieve the hardness difference between the elastic layer of hardness and low elastic modulus. Due to the presence of the intermediate layer, it has intermediate hardness and elastic modulus between the surface layer and the elastic layer, can buffer the difference, reduce friction under high speed, and can cope with further high-speed output. , Delamination can be suppressed. Then, the selection of the mechanical properties and chemical composition of the elastic layer and the surface layer and the selection range of the combination can be expanded.

  The composite elastic modulus (Erm) of the intermediate layer is preferably 50 MPa or more and 5000 MPa or less. If it is 50 MPa or more, it is possible not only to suppress delamination and excellent durability, but also to suppress image defects caused by compressive deformation distortion. Moreover, if it is 5000 MPa or less, an excessive increase in hardness can be suppressed, an image deterioration due to toner deterioration due to repeated image output can be suppressed, and the stress between layers can be relieved due to an excessive difference in elastic modulus with the elastic layer. Can be achieved.

  The thickness of the intermediate layer is preferably 2 μm or more and 100 μm or less. When it is 2 μm or more, it can sufficiently function as a buffer layer and not only obtain good durability peeling performance, but also suppress image adverse effects such as image streaks due to deformation at the contact portion with the toner regulating member. it can. Further, when the thickness is 100 μm or less, it is possible to suppress an excessive increase in hardness and to suppress image defects due to toner deterioration due to repeated image output. Furthermore, the effect of relaxing the stress between the layers can be sufficiently obtained, and good durable peeling performance can be obtained.

  The film thickness of the intermediate layer is a total of 9 using a digital microscope (VH-2450: KEYENCE CORPORATION) in the longitudinal direction of the developing roller at three equal intervals from the end portion and at three equal intervals in the circumferential direction. A place can be measured and it can obtain | require as an arithmetic mean value of the obtained value. Further, when the intermediate layer contains fine particles or the like, the measured value of the matrix portion is adopted.

  As the rubber as the main ingredient of the intermediate layer, the same rubber as exemplified as the rubber used for the elastic layer can be used. Among these, the composite elastic modulus (Ere) larger than the composite elastic modulus (Ere) of the elastic layer can be used. The kind, the crosslinking density, etc. are selected so as to have Erm). Further, the composite elastic modulus (Erm) of the intermediate layer can be adjusted by selection and content of the filler and extender.

  Among these, polyurethane, polyester, nylon and the like can be mentioned as preferable from the viewpoints of wear resistance, mechanical properties, adhesion to the elastic layer, and the like. In particular, polyurethane is preferable from the viewpoint of stress resistance between the surface layer and the elastic layer due to rubbing or contact, and suppression of deformation due to the contact member, since it exhibits wear resistance and excellent mechanical properties. Furthermore, thermosetting polyurethane is particularly preferable because it has excellent compression set, can suppress deformation due to the contact member, and is excellent in stress relaxation and wear resistance.

  Polyurethane is a polymer having a urethane bond, and is composed of two segments, a hard segment and a soft segment. A hard segment is comprised from the segment containing bonds, such as a urethane bond, an allophanate bond, and biuret bond. A soft segment is comprised from the segment which has functional groups, such as an ether group, ester group, a carboxyl group, an alkyl group, and an alkenyl group. These polyurethanes are obtained from a polyol constituting a soft segment and an isocyanate compound. Specific examples of the polyol include the following.

  Polycarbonate polyol, acrylic polyol, caprolactone polyol, polyether polyol, polyester polyol, polyolefin polyol. These may be used as a mixture. In addition, prepolymer polyols obtained by re-elongating these polyols with isocyanate can also be suitably used. Among these, polyether polyol, polyester polyol, polycaprolactone polyol, polycarbonate polyol, or a mixture thereof is particularly preferable.

  Specific examples of the polyether polyol include those using polyethylene glycol (PEG), polypropylene glycol (PPG), polytetramethylene glycol (PTMG), a copolymer of THF and neopentyl glycol (PTXG), and the like.

  As the polyester polyol, a polyester polyol obtained by direct esterification reaction or ring-opening polymerization reaction, or a polyurethane polyol prepolymer obtained by extending the chain of polyester polyol and isocyanate can be suitably used. The polyester polyol synthesized by direct esterification is obtained by dehydrating and condensing a polybasic acid and a polyhydric alcohol as raw materials. Specific examples of the polybasic acid used as the raw material for the polyester polyol include the following.

  Adipic acid, isophthalic acid, tetrachlorophthalic anhydride, het acid, tetrabromophthalic anhydride, phthalic anhydride, hasophthalic acid, terephthalic acid, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, succinic acid, sebacic acid, fumaric acid, tri Merit acid. Dimer acid, maleic anhydride, 1,12-dodecanedioic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 5-sodiosulfoisophthalic acid and the like. Among these, adipic acid, isophthalic acid, terephthalic acid, and sebacic acid are particularly preferable because they are easily available.

  Specific examples of the polyhydric alcohol include the following. 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, ethylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentyl Glycol. Bisphenol A, glycerin, pentaerythritol, trimethylolpropane, trimethylolethane, 1,4-cyclohexanedimethanol, 2,2,4-trimethyl-1,3-pentanediol, 2-butyl-2-ethyl-1, 3-propanediol.

  Hydroxybivalyl hydroxybivalate, 3-methyl-1,5-pentanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 2-methyl-1,3-propanediol, 2,4 -Diethyl-1,5-pentanediol and the like.

  Examples of the polycaprolactone polyol include polycaprolactone diol obtained by ring-opening polymerization reaction using ε-caprolactone as a raw material, or a prepolymer type polyol synthesized by prepolymerizing polycaprolactone diol. Among the polycaprolactone diols, those having non-crystalline or low melting points are particularly preferable from the viewpoint of mechanical properties.

  The intermediate layer may contain carbon black for imparting conductivity and controlling mechanical properties. The content of carbon black in the surface layer is 5 parts by mass or more and 60 parts by mass with respect to 100 parts by mass of the resin component of the intermediate layer from the viewpoint of imparting conductivity in an appropriate range to the developing roller and controlling mechanical properties. Part or less. When the content of carbon black in the intermediate layer is 5 parts by mass or more, not only moderate conductivity can be obtained, but also compression set can be suppressed. On the other hand, if it is 60 parts by mass or less, not only the dispersion uniformity with respect to the resin component can be obtained, but also the hardness increase of the intermediate layer can be suppressed, and a high-quality image can be obtained.

  The average primary particle size of the carbon black is preferably set to 15 to 50 nm in order to maintain the strength of the intermediate layer and exhibit appropriate conductivity. The DBP oil absorption of carbon black is preferably 50 to 300 ml / 100 g, for the same reason. As such carbon black, what was manufactured by the channel method, the furnace method, etc. can be used conveniently. Furthermore, you may mix | blend 2 or more types of carbon black according to a required physical property.

  The intermediate layer may contain fine particles in order to impart an appropriate surface roughness to the surface of the developing roller. By including fine particles in the intermediate layer, the surface roughness of the surface of the developing roller can be controlled, and at the same time, even when the surface layer is worn, fluctuation of the surface roughness is reduced and the surface state is kept constant. Can do. The fine particles preferably have a volume average particle size of 2 to 40 μm.

  For the measurement of the volume average particle diameter of the fine particles, a LS-230 type laser diffraction particle size distribution measuring device manufactured by Coulter, Inc., to which a liquid module is attached can be used. For measurement, a small amount of surfactant is added to about 10 cc of water, about 10 mg of fine particles are added thereto, and the mixture is dispersed for 10 minutes with an ultrasonic disperser, and then measured under the conditions of a measurement time of 90 seconds and a single measurement. . The value measured by the above measurement method can be adopted as the value of the volume average particle diameter. Further, the volume average particle diameter of the particles can be taken out from the intermediate layer using a manipulator or the like and measured.

  As content of microparticles | fine-particles, it is preferable that it is 1-100 mass parts with respect to 100 mass parts of resin of an intermediate | middle layer. Examples of the material of the fine particles include urethane resin, polyester resin, polyether resin, acrylic resin, and polycarbonate resin. These fine particles can be produced, for example, by suspension polymerization or dispersion polymerization.

  As a method for forming the intermediate layer, a composition containing uncured resin and other component materials (referred to as an uncured composition) is prepared, and a coating film is formed on the elastic layer using the composition. The method of hardening can be mentioned. For the preparation of the uncured composition, it is preferable to use a dispersion apparatus using beads such as a sand mill, a paint shaker, a dyno mill, a pearl mill using methyl ethyl ketone, toluene, or alcohol as a solvent.

  A coating method such as spraying, dip coating, or roll coating can be used for forming the coating film. After the coating film is formed on the elastic layer, it is dried to remove the solvent and cure by heating. The method can be used. Curing and drying may be either heating or electron beam irradiation. Furthermore, you may coat | cover the intermediate | middle layer previously shape | molded in the tube shape on the roller in which the elastic layer was formed.

  When dip coating is used for the coating film formation, it is preferable to use a coating apparatus having a paint circulation mechanism shown in the schematic configuration diagram of FIG.

  A dipping tank 6 is provided in the coating apparatus shown in FIG. The immersion tank has a cylindrical shape with an inner diameter slightly larger than the outer diameter of the roller 7 on which the elastic layer 4 is formed and a depth longer than the axial length of the roller 7 and is installed with the axial direction vertical. The An annular liquid receiving portion 9 is provided on the outer periphery of the upper end portion, and the liquid receiving portion is connected to the stirring tank 8 by a pipe 10 connected to the bottom surface thereof.

  On the other hand, the bottom of the immersion tank 6 is connected to a pump 12 that circulates the intermediate layer forming paint 11 through a pipe 14, and is further connected to the stirring tank 8 by a pipe 13 that connects the pump 12 and the stirring tank 8. The stirring tank 8 is provided with a stirring blade 15 for stirring the intermediate layer forming paint 11 accommodated therein.

  This coating apparatus is provided with an elevating device 16 that raises and lowers the elevating plate 17 in the axial direction of the immersing tank in the upper part of the immersing tank, and the roller 7 suspended on the elevating plate 17 can enter and retract into the immersing tank. ing.

  In order to form the intermediate layer on the elastic layer using such a coating apparatus, the pump 12 is driven, and the intermediate layer forming coating material 11 stored in the stirring tank 8 is passed through the pipes 13 and 14 into the immersion tank 6. Supply. The elevating device 16 is driven to lower the elevating plate 17, and the roller 7 is allowed to enter the immersion tank 6 filled with the intermediate layer forming paint 11. The intermediate layer forming coating material 11 overflowing from the upper end 6 a of the immersion tank due to the entrance of the roller 7 is received by the liquid receiving portion 9 and returned to the stirring tank 8 through the pipe 10. Thereafter, the elevating device is driven to raise the elevating plate, and the roller 7 is retracted from the dipping tank at a predetermined speed to form a coating film on the elastic layer.

  During this time, the stirring blade 15 is rotated in the stirring tank to stir the coating solution to suppress sedimentation of the contents and maintain the uniformity of the coating solution. The roller on which the coating film is formed is removed from the elevating plate 17, and the coating film is dried and cured to form the intermediate layer.

[Surface layer]
The above surface layer is a layer constituting the laminate, and is located on the surface side of the laminate, contains organosiloxane, and continuously contains carbon atoms chemically bonded to silicon atoms and oxygen atoms bonded to silicon atoms. (Hereinafter sometimes referred to as “SiOx film”). The silicon atom of the carbon atom in which the abundance ratio (O / Si) of the oxygen atom chemically bonded to the silicon atom is 0.65 or more and 1.95 or less and which forms a chemical bond with the silicon atom The abundance ratio (C / Si) is 0.05 to 1.65.

  The abundance ratio O / Si of oxygen atoms chemically bonded to silicon atoms is more preferably 1.30 or more and 1.80 or less. When the abundance ratio O / Si is 0.65 or more, the surface is prevented from becoming sticky, and when used as a developing roller, it has excellent releasability with respect to toner and can suppress the occurrence of initial filming. it can. If O / Si is 1.95 or less, the SiOx film can be prevented from cracking due to its high hardness, and when used as a developing roller, it is stressed by rubbing against the contact member. It is difficult to suppress the occurrence of delamination and image defects.

  The abundance ratio C / Si of the carbon atom chemically bonded to the silicon atom is more preferably 0.10 or more and 0.70 or less. When the abundance ratio C / Si is 0.05 or more, the adhesion between the silicon oxide film and the intermediate layer is excellent, the occurrence of peeling is suppressed, and a uniform and appropriate surface layer can be obtained. In addition, if the abundance ratio C / Si is 1.65 or less, the film surface is prevented from becoming sticky, and when used as a developing roller, the releasability to toner is good, and initial filming occurs. Can be suppressed.

  The abundance ratio of each element in the surface layer can be determined as follows. Using an X-ray photoelectron spectrometer (Quantum2000: ULVAC-PHI Co., Ltd.), measuring the peak due to the binding energy of the 2p orbital of Si and the 1s orbital of O and C with the surface of the surface layer as AlKα. To do. The abundance ratio of each atom is calculated from each peak, and O / Si and C / Si are obtained from the obtained abundance ratio.

Moreover, about the chemical bond of SiOx, the surface of the surface layer is IR-measured with a Fourier transform infrared spectroscopic analysis (FT-IR) apparatus (SpectrumOne: manufactured by PerkinElmer Japan Co., Ltd.). The presence of the Si—O chemical bond is confirmed by the vibration peak at 450 cm ⁻¹ , and the presence of the Si—C chemical bond is confirmed by the stretching peak at 800-820 cm ⁻¹ . In the surface layer formed by the method described later, there is almost no variation at the O / Si and C / Si values, so it is sufficient to perform the measurement at one location on the surface layer.

  The method for forming the surface layer is not particularly limited, and can be formed by the following method. Wet coating methods such as dip coating, spray coating, roll coating, and ring coating; physical vapor deposition (PVD) methods such as vacuum deposition, sputtering, and ion plating; chemical vapor deposition such as plasma CVD, thermal CVD, and laser CVD Phase growth (CVD) method. Among these, the plasma CVD method is preferable in consideration of adhesion between the elastic layer and the surface layer, processing time and processing temperature, simplicity of the apparatus, and uniformity of the obtained surface layer.

Hereinafter, as an example of a method for forming the SiOx film by the plasma CVD method, a method using the plasma CVD apparatus shown in the schematic diagram of FIG. 2 will be described. The plasma CVD apparatus includes a vacuum chamber 18, a plate electrode 19 placed in parallel, a raw material gas cylinder and a raw material liquid tank 20, a raw material supply switching valve 21, a gas exhaust means 22 in the chamber, a high frequency power supply 23 for supplying high frequency, It has a rotation support device 24 for the roller of the processing body. The surface layer is formed by the following procedure.
(1) An elastic roller in which an elastic layer and an intermediate layer are formed on a shaft core body is installed between the flat plate electrodes 19, and the rotation support device 24 is driven so that the obtained SiOx film is uniform, whereby the elastic roller Rotate in the circumferential direction.
(2) The vacuum chamber 18 is evacuated by the exhaust means.
(3) The source gas is introduced from the source gas introduction port, high frequency power is supplied to the flat plate electrode 19 by the high frequency power supply 23, plasma is generated, and film formation is performed on the elastic roller.
(4) After a predetermined time has elapsed, the supply of the source gas and the high-frequency power is stopped, air or nitrogen is introduced (leaked) into the vacuum chamber 18 to atmospheric pressure, and the elastic roller is taken out.

  A developing roller having a surface layer made of a SiOx film containing carbon can be manufactured by the above procedure. As long as a uniform plasma atmosphere is formed, many elastic rollers subjected to plasma CVD processing can be processed simultaneously. As a raw material gas, a gaseous or gaseous organosilicon compound is usually introduced together with a hydrocarbon compound, if necessary, in the presence or absence of a gas such as an inert gas or an oxidizing gas. Examples of the hydrocarbon compound include toluene, xylene, methane, ethane, propane, acetylene, and the like.

  Examples of the organosilicon compound include the following. 1,1,3,3-tetramethyldisiloxane, hexamethyldisiloxane, vinyltrimethylsilane, methyltrimethoxysilane, hexamethyldisilane, methylsilane, dimethylsilane, trimethylsilane, tetramethylsilane, diethylsilane, propylsilane. Phenylsilane, vinyltriethoxysilane, vinyltrimethoxysilane, tetramethoxysilane, tetraethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, octamethylcyclotetrasiloxane.

  Of these, 1,1,3,3-tetramethyldisiloxane, hexamethyldisiloxane, and tetramethylsilane are preferable from the viewpoint of safety in handling.

  The silane source is not limited to the organosilicon compound, and silane, aminosilane, and silazane can also be used.

If the organosilicon compound is in a gaseous state, it is used as it is, and if it is liquid at room temperature, it is heated and vaporized and transported with an inert gas, or is bubbled with an inert gas and transported. Furthermore, in the case of a solid at room temperature, it is heated and vaporized, and is transported by an inert gas. Moreover, vaporization may be promoted in a reduced pressure state of the raw material. When the organic silicon compound as a raw material is an oxygen-containing compound, it is not necessary to supply oxygen gas. However, together with the raw material gas, an oxidizing gas such as oxygen or oxygen-containing gas (N ₂ O, CO _2, etc.) is used. Introduce. In addition, an inert gas such as helium, argon, or nitrogen can also be used as a dilution gas as appropriate.

  The abundance ratio of silicon atoms, oxygen atoms chemically bonded to silicon atoms, and carbon atoms chemically bonded to silicon atoms in the SiOx film should be controlled by the mixing ratio of the raw material gas to be introduced, the high frequency power supplied, etc. Is possible.

  Specifically, for example, in the blending ratio of the organosilicon compound and oxygen gas, the value of O / Si can be increased by increasing the ratio of oxygen gas. The value of C / Si can be increased by reducing the ratio of oxygen gas. Moreover, the value of O / Si and C / Si can be reduced by increasing the high frequency power. Further, by using the hydrocarbon compound in combination, the values of O / Si and C / Si can be increased according to the amount of the hydrocarbon compound used.

  Moreover, the following method can be mentioned as a manufacturing method of the SiOx film | membrane by a wet method. A mixture of an inorganic polymer precursor solution (for example, perhydropolysilazane solution) and a polymer solution having a hydroxyl group (for example, 2-hydroxyethyl methacrylate) is uniformly applied on the elastic layer, and then heated or irradiated with ultraviolet rays. The coating of the mixture is cured by irradiation. The values of O / Si and C / Si can be controlled by changing the molar ratio between the inorganic polymer precursor solution and the polymer solution.

  Prior to applying the raw material paint for the SiOx film on the intermediate layer, as in the formation of the intermediate layer, in order to improve the wettability of the intermediate layer surface with respect to the paint, ultraviolet irradiation, electron beam irradiation, flame treatment or Activation processing such as plasma processing may be performed.

  The thickness of the surface layer is preferably 15 nm or more and 5000 nm or less. More preferably, it is 300 nm or more and 3000 nm or less. If the film thickness is within this range, it will have good durability against wear associated with long-term use, and even when the surface layer is formed by the CVD method, the elastic layer will be excessively heated and its characteristics will be It is possible to suppress the change. The film thickness of the surface layer is a total of 9 using a thin film measuring apparatus (F20-EXR; manufactured by FILMETRICS) at three locations at equal intervals in the longitudinal direction of the developing roller and at equal intervals in the circumferential direction. A place can be measured and it can obtain | require as an arithmetic mean value of the obtained value.

[Development roller]
The developing roller preferably has an Asker C hardness of 50 degrees or more and less than 80 degrees, and more preferably 55 or more and 70 or less. If the Asker C hardness is 50 degrees or more, the stress relaxation effect between the layers can be sufficiently obtained, a good durability peeling performance can be obtained, and an image due to compression set due to long-term pressure contact with the toner regulating member can be obtained. Generation of streaks can be suppressed. In addition, if the Asker C hardness is less than 80 degrees, it is possible to reduce damage to the contacted photoconductor, toner regulating member, toner, etc., and filming due to surface layer peeling or toner deterioration under high-speed image output. Can be suppressed.

  The Asker C hardness is a hardness measured using an Asker-C hardness type spring type rubber hardness meter (manufactured by Kobunshi Keiki Co., Ltd.) in accordance with the Japan Rubber Association standard SRIS101. The measurement condition is that the developing roller is left in an environment of normal temperature and normal humidity (temperature 23 ° C., humidity 50% RH) for 12 hours or more and then measured 30 seconds after the hardness meter is brought into contact with a force of 10 N. The sample for measuring Asker C hardness is obtained by cutting out and stacking an elastic layer, an intermediate layer, and a surface layer, and the thickness may be at least 5 mm. The developing roller having such hardness can be obtained by appropriately selecting the surface layer having the above-described configuration, a filler such as carbon black, and the like.

  The surface roughness of the developing roller is preferably 0.10 μm or more and 2.5 μm or less, more preferably 0.30 μm or more and 2.0 μm or less, in terms of centerline average roughness Ra. If Ra is 0.10 μm or more, it is possible to suppress an increase in the adhesiveness of the surface of the developing roller, and it is possible to suppress the occurrence of delamination due to an increase in friction with the contact member. Further, it is possible to suppress the toner transportability from being lowered, and to suppress the occurrence of image streaks due to compression set by the contact member.

  Further, if Ra is 2.5 μm or less, the adhesiveness of the surface is lowered, but the friction with the contact member is increased due to the influence of the surface irregularity shape, thereby suppressing the tendency for delamination to occur. it can. Furthermore, it is possible to suppress the occurrence of filming due to toner deterioration due to excessive toner transportability. Depending on the combination with the toner and the electrophotographic image forming process, if Ra is within the above numerical range, it is particularly excellent in durability peeling performance, and defects caused by toner fixation, filming, compression set by contact members, etc. The balance to suppress the image becomes good.

  In order to obtain a developing roller having such a surface roughness, a method of polishing the surface after forming an elastic layer or an intermediate layer, a method of containing spherical fine particles of an arbitrary particle size in the intermediate layer or the elastic layer, etc. Can be.

  Ra is based on JIS standard (JISB0601-2001), measured using a surfcoder SE-3400 manufactured by Kosaka Laboratory, under conditions of a feed rate of 0.5 mm / s, a cutoff of 0.8 mm, and a measurement length of 2.5 mm. To do. This measurement is performed at any three locations in the roller generatrix direction, and a value obtained as an arithmetic mean can be adopted.

  The developing roller preferably has a current value of 5 μA or more and 3000 μA or less measured when the developing roller is rotated and DC 50 V is applied. This current value is obtained by applying a load of 500 g to both ends of the shaft core of the developing roller, pressing it against a metal drum rotating at 24 rpm, and measuring the current flowing through an internal resistance of 10 kΩ connected in series with the developing roller. This is the value obtained. The measurement is performed at 23 ° C. and 50% RH, and the developing roller is rotated to measure one round, and the average value is obtained. Controlling the current value of the developing roller appropriately and uniformly is important from the viewpoint of maintaining the electric field strength for moving the toner appropriately and uniformly.

  An example of the developing roller of the present invention is shown in FIG. The developing roller shown in FIG. 3 has an intermediate layer 4 in which an elastic layer 3 is fixed to the outer peripheral surface of a columnar or cylindrical conductive shaft core 2 and an intermediate layer 4 is laminated on the outer peripheral surface of the elastic layer 3. 4 has a configuration in which a surface layer 5 is laminated on the outer peripheral surface of the substrate 4. Further, the elastic layer 3, the intermediate layer 4, and the surface layer 5 may have a multilayer structure having different materials and compositions. When there are two or more intermediate layers, the layer in contact with the surface layer 5 is the intermediate layer in the developing roller of the present invention.

[Electrophotographic process cartridge]
The electrophotographic process cartridge of the present invention is detachably attached to the main body of the electrophotographic image forming apparatus, has at least a developing roller, a toner regulating member, and a toner container, and the developing roller is the developing roller. An example of an electrophotographic process cartridge according to the present invention is shown in FIG.

  The electrophotographic process cartridge 25 is an all-in-one process cartridge in which a photoconductor 26, a cleaning blade 34, a waste toner container 33, and a charging member 32 are integrated with a developing device 30. The developing device 30 includes the developing roller 1, the toner regulating member 29, the toner supply roller 27, and a toner container 28 for storing the toner 28a.

[Electrophotographic image forming apparatus]
The electrophotographic image forming apparatus of the present invention has a photosensitive member and a developing roller disposed in contact with the photosensitive member, and the developing roller is the developing roller. An example of the electrophotographic image forming apparatus of the present invention is shown in FIG. In this electrophotographic image forming apparatus, the electrophotographic process cartridge 25 is detachably mounted for each color, but the photosensitive member 26, the cleaning blade 34, the waste toner container 33, and the charging member 32 are included in the main body. It may be deployed.

  The photosensitive member 26 rotates in the direction of the arrow, and is uniformly charged by a charging member 32 for charging the photosensitive member 26. An electrostatic latent image is formed. The electrostatic latent image is developed by applying a toner 28a by a developing device 30 disposed in contact with the photoreceptor 26, and visualized as a toner image.

  The development is so-called reversal development in which a toner image is formed on the exposed portion. The visualized toner image on the photoreceptor 26 is transferred to a paper 42 as a recording medium by a transfer roller 37 as a transfer member. The paper 42 is fed into the apparatus through a paper feed roller 43 and a suction roller 44, and is conveyed between the photoconductor 26 and the transfer roller 37 by an endless belt-like transfer conveyance belt 40.

  The transfer conveyance belt is suspended from a driven roller 41, a drive roller 36, and a tension roller 39, and moves endlessly in the direction of the arrow. A voltage is applied to the transfer roller 37 and the suction roller 44 from a bias power source 38, the toner image on the photoconductor is transferred onto the paper 42, and the toner images of the respective colors are sequentially superimposed on the paper 42, and are fixed by the fixing device 35. The paper on which the toner image has been heat-fixed is discharged out of the apparatus, and the printing operation is completed.

  On the other hand, the untransferred toner remaining on the photosensitive member 26 without being transferred is scraped off by the cleaning blade 34 and stored in the waste toner container 33, and the cleaned photosensitive member 26 repeats the above operation.

  The developing device 30 is a developing container containing a toner 28a of a one-component developer, and developing as a developer carrying member that is located in an opening extending in the longitudinal direction in the developing container and is placed opposite to the photosensitive member 26. A roller 1. As the toner regulating member 29, a member in which a rubber elastic body is fixed to a metal sheet metal, a thin plate member having a spring property of SUS or phosphor bronze, or a member in which resin or rubber is laminated on the surface thereof is used, which is higher than the developing roller. A voltage is applied to control the toner layer on the developing roller.

  The voltage applied from the bias power source 38 to the developing roller and the toner regulating member 29 is preferably 100 V to 300 V larger in absolute value than the developing roller with respect to the toner regulating member 29.

  The developing process in the developing device 30 will be described below. Toner is applied onto the developing roller 1 by a toner supply roller 27 that is rotatably supported. The toner applied on the developing roller 1 is rubbed against the toner regulating member 29 as the developing roller 1 rotates. Here, the toner applied on the developing roller is uniformly coated on the developing roller by the bias applied to the toner regulating member 29. The developing roller 1 is in contact with the photosensitive member 26 while rotating, and the toner coated on the developing roller 1 is attached to the electrostatic latent image formed on the photosensitive member 26 to form a toner image.

Hereinafter, the developing roller, electrophotographic process cartridge, and electrophotographic image forming apparatus of the present invention will be described in detail. Hereinafter, “part” means “part by mass”.
[Preparation of elastic layer roller 1]
As a reactive group, the following liquid silicone rubber base material A having vinyl groups and liquid silicone rubber base material B having vinyl groups and SiH groups are mixed at a mass ratio of 1: 1, and the unvulcanized silicone rubber is thermally cured. Thus, the elastic layer roller 1 was produced.
(Liquid silicone rubber base material A having vinyl group)
Dimethylpolysiloxane having vinyl groups at both ends and having a weight average molecular weight (Mw) of 85000: 100 parts by mass Carbon black (trade name: Ketjen Black EC-DJ600, manufactured by Ketjen Black International): 2 parts by mass Carbon black (trade name: Printex L, manufactured by Evonik Degussa Japan): 3 parts by mass (liquid silicone rubber base material B having SiH group and vinyl group)
Dimethylpolysiloxane having vinyl groups at both ends and having a weight average molecular weight (Mw) of 85000: 100 parts by mass Carbon black (trade name: Ketjen Black EC-DJ600, manufactured by Ketjen Black International): 2 parts by mass Carbon black (trade name: Printex L, manufactured by Evonik Degussa Japan): 3 parts by mass Curing catalyst (2% by mass of isopropanol solution of chloroplatinic acid in 10 ppm with respect to dimethylpolysiloxane): 0. 5 parts by mass / methyl hydrogen polysiloxane: 3 parts by mass (the amount of SiH groups is 1.1 mol with respect to 1 mol of vinyl groups contained in base materials A and B)
As a shaft core, a primer (trade name: DY35-051, manufactured by Toray Dow Corning Co., Ltd.) is applied to a SUS304 core metal with a diameter of 8 mm so as to have a thickness of about 1 μm and baked at 150 ° C. for 30 minutes. Was used. Next, the shaft core was placed in a mold, and the unvulcanized silicone rubber was injected into a cavity formed in the mold. Subsequently, the mold was heated to cure and cure the unvulcanized silicone rubber at 150 ° C. for 15 minutes, and then demolded after cooling. Thereafter, the mixture was further heated at 180 ° C. for 1 hour to complete the curing reaction, and an elastic layer was provided around the shaft core body. The produced elastic layer roller 1 had a diameter of 12 mm and a composite elastic modulus (Ere) of 0.5 MPa.

[Production of Elastic Layer Roller 2]
The following materials were kneaded using a twin screw extruder having a diameter of 30 mm and L / D32, and extruded to prepare a resin mixture.
Styrene butadiene elastomer (trade name: SL563, manufactured by JSR Corporation): 100 parts by mass Polyolefin polyol (trade name: G-3000, manufactured by Nippon Soda Co., Ltd.): 30 parts by mass Carbon black (trade name: Printex U , Manufactured by Evonik Degussa Japan): 40 parts by mass, calcium carbonate (trade name: Nanox # 30, manufactured by Maruo Calcium Co., Ltd.): 60 parts by mass, polyethylene glycol (trade name: PEG # 4000, manufactured by NOF Corporation) : 1 part by mass-Zinc oxide (trade name: activated zinc white, manufactured by Sakai Chemical Industry Co., Ltd.): 5 parts by mass-Zinc stearate (trade name: SZ-P, manufactured by Sakai Chemical Industry Co., Ltd.): 2 parts by mass Vulcanization accelerator 1 (trade name: Noxeller M, manufactured by Ouchi Shinsei Co., Ltd.): 0.5 parts by mass ・ Vulcanization accelerator 2 (trade name: Noxeller TRA, emerging Ouchi) 1.2 parts by mass of sulfur (trade name: Sulfax PMC, manufactured by Tsurumi Chemical Co., Ltd.): 1.6 parts by mass Next, the resin mixture was pelletized. This pellet was extruded on a shaft core (diameter 6 mm, length 250 mm) using a crosshead extruder to form an elastic layer. The elastic layer 2 having an elastic layer having a thickness of 3 mm was obtained by cutting the end portion of this elastic layer and further polishing the elastic layer portion using a rotating grindstone (GC # 80) under the following conditions. The produced elastic layer roller 2 had a diameter of 12 mm and a composite elastic modulus (Ere) of 20 MPa.

[Production of Elastic Layer Roller 3]
An elastic layer roller 3 was produced in the same manner as the elastic layer roller 1 except that the following silicone rubber base materials A and B were used.
(Silicon rubber base material A having vinyl group)
Dimethylpolysiloxane having vinyl groups at both ends and having a weight average molecular weight (Mw) of 85000: 100 parts by mass Carbon black (trade name: Raven 860 Ultra, manufactured by Columbian Chemical): 8 parts by mass Silica (trade name: Leolosil MT -10, manufactured by Tokuyama Corporation): 10 parts by mass (liquid silicone rubber base material B having SiH group and vinyl group)
Dimethylpolysiloxane having vinyl groups at both ends and having a weight average molecular weight (Mw) of 85000: 100 parts by mass Carbon black (trade name: Raven 860 Ultra, manufactured by Columbian Chemical): 8 parts by mass Silica (trade name: Leolosil MT -10, manufactured by Tokuyama Corporation): 10 parts by mass / curing catalyst (2% by mass of an isopropanol solution of chloroplatinic acid mixed with 10 ppm with respect to dimethylpolysiloxane): 0.5 parts by mass / methyl hydrogen polysiloxane: 3 parts by mass (the amount of SiH group is 1.1 mol with respect to 1 mol of vinyl group contained in base materials A and B)
The produced elastic layer roller 3 had a diameter of 12 mm and a composite elastic modulus (Ere) of 2.0 MPa.

[Production of Elastic Layer Roller 4]
An elastic layer roller 5 was produced in the same manner as the elastic layer roller 1 except that the following silicone rubber base materials A and B were used.
(Silicon rubber base material A having vinyl group)
Dimethylpolysiloxane having vinyl groups at both ends and having a weight average molecular weight (Mw) of 85000: 100 parts by mass Carbon black (trade name: Ketjen Black EC-DJ600, manufactured by Ketjen Black International): 3 parts by mass (Liquid silicone rubber base material B having SiH group and vinyl group)
Dimethylpolysiloxane having vinyl groups at both ends and having a weight average molecular weight (Mw) of 85000: 100 parts by mass Carbon black (trade name: Ketjen Black EC-DJ600, manufactured by Ketjen Black International): 3 parts by mass・ Curing catalyst (2 mass% of isopropanol solution of chloroplatinic acid mixed with 10 ppm with respect to dimethylpolysiloxane): 0.5 part by mass ・ Methyl hydrogen polysiloxane: 3 parts by mass (contained in base materials A and B) The amount of SiH group becomes 1.1 mol per 1 mol of vinyl group)
The produced elastic layer roller 5 had a diameter of 12 mm and a composite elastic modulus (Ere) of 0.4 MPa.

[Production of Elastic Layer Roller 5]
The elastic layer roller 5 was produced in the same manner as the elastic layer 2 except that the amount of polyolefin polyol (trade name: G-3000, manufactured by Nippon Soda Co., Ltd.) was changed from 30 parts by mass to 28 parts by mass. The produced elastic layer roller 5 had a diameter of 12 mm and a composite elastic modulus (Ere) of 22 MPa.

[Production of Elastic Layer Roller 6]
The elastic layer roller 6 was produced in the same manner as the elastic layer 2 except that the amount of polyolefin polyol (trade name: G-3000, manufactured by Nippon Soda Co., Ltd.) was changed from 30 parts by mass to 5 parts by mass. The produced elastic layer roller 6 had a diameter of 12 mm and a composite elastic modulus (Ere) of 50 MPa.

Subsequently, intermediate layer forming coating liquids in Examples and Comparative Examples of the present invention were prepared.
[Preparation of intermediate layer forming coating liquid (1)]
Ester diol (trade name: P-5010, manufactured by Kuraray Co., Ltd.): 100 parts by mass Ester-modified isocyanate (trade name: Coronate 4076, manufactured by Nippon Polyurethane Industry Co., Ltd.): 89 parts by weight Material for coating liquid for forming an intermediate layer As above, the above components were mixed to obtain a resin component. Subsequently, 20 parts by mass of carbon black (trade name: MA-11, manufactured by Mitsubishi Chemical Corporation) and MEK were added to 100 parts by mass of the solid content of the resin component, and the mixture was stirred with a motor for one hour. Subsequently, MEK was further added so that the total solid content ratio was 33% by mass, and the mixture was further stirred with a motor for one hour.

  Subsequently, the above mixed solution was uniformly dispersed with a horizontal dispersion NVM-03 (trade name, manufactured by IMEX) under conditions of a peripheral speed of 7 m / sec, a flow rate of 1 cc / min, and a dispersion temperature of 15 ° C. for 3 hours. During the dispersion, glass beads having a diameter of 1.5 mm (trade name: DMB503B, manufactured by Hotters Ballotinis) were used. Next, 30 parts by mass of crosslinked urethane beads (trade name: Art Pearl C-800 transparent, manufactured by Negami Kogyo Co., Ltd.) are added as resin particles for adjusting the roughness to 100 parts by mass of the solid content of the resin component. Dispersed for 30 minutes.

  Next, this solution was diluted with MEK so as to have a solid content of 27% by mass, and this solution was filtered through a 300-mesh net to prepare an intermediate layer forming coating liquid (1).

[Preparation of intermediate layer forming coating liquids (2) to (12)]
The resin main raw material, carbon black, roughness-adjusting resin particles, and dilution solvent were selected from those shown below and used as shown in Table 1 in the same manner as in the intermediate layer-forming coating liquid (1). Intermediate layer forming coating liquids (2) to (12) were prepared.
[Resin component]
[Polyol]
Polyester diol (trade name: P-5010, 3-methyl, 1,5-pentanediol and adipic acid, manufactured by Kuraray Co., Ltd.)
Polyester diol (trade name: P-6010, 3-methyl, 1,5-pentanediol and adipic acid, manufactured by Kuraray Co., Ltd.)
・ Polycaprolactone diol (trade name: L-212AL, manufactured by Daicel Chemical Industries, Ltd.)
・ Polycaprolactone diol (trade name: L-205AL, manufactured by Daicel Chemical Industries, Ltd.)
Polycarbonate diol (trade name: T-5650J, manufactured by Asahi Kasei Chemicals Corporation)
[One-part curable polymer]
・ Thermoplastic polyester resin (trade name: NIPPOLAN 5111, manufactured by Nippon Polyurethane Industry Co., Ltd.)
・ Soluble copolymer nylon resin (trade name: CM8000, manufactured by Toray Industries, Inc.)
・ Soluble copolymer nylon resin (trade name: CM4000, manufactured by Toray Industries, Inc.)
[Isocyanate compound]
・ Polyester-modified isocyanate (trade name: Coronate 4076, manufactured by Nippon Polyurethane Industry Co., Ltd.)
・ Polyester-modified isocyanate (trade name: Coronate 4047, manufactured by Nippon Polyurethane Industry Co., Ltd.)
-Polyether-modified isocyanate (trade name: Coronate 4192, manufactured by Nippon Polyurethane Industry Co., Ltd.)
・ Polyester-modified isocyanate (trade name: Coronate 4048, manufactured by Nippon Polyurethane Industry Co., Ltd.)
[Carbon black]
-Product name: MA-11, manufactured by Mitsubishi Chemical Corporation-Product name: Printex 35, manufactured by Evonik Degussa Japan [Roughness adjusting resin particles]
・ Cross-linked urethane beads (trade name: Art Pearl C-800 transparent, manufactured by Negami Kogyo Co., Ltd.)
・ Cross-linked acrylic beads (trade name: J-4PY, manufactured by Negami Industrial Co., Ltd.)

Example 1 Preparation of Developing Roller 1 First, the elastic layer roller 1 was subjected to a surface treatment by excimer UV treatment. Surface treatment is performed by irradiating UV light having a wavelength of 172 nm with a capillary excimer lamp (manufactured by Harrison Toshiba Lighting Co., Ltd.) so that the integrated light quantity becomes 150 mJ / cm ² while rotating the shaft core of the elastic layer roller 1 at 30 rpm. Was done. The distance between the elastic layer surface and the excimer lamp at the time of irradiation was 2 mm.

  Thereafter, the intermediate layer-forming coating material 1 was applied using a dipping coating method to form an intermediate layer. In the formation of the intermediate layer, 250 cc of the intermediate layer forming coating (1) with the liquid temperature maintained at 23 ° C. was injected from the bottom of the cylinder having an inner diameter of 32 mm and a length of 300 mm per minute, and the liquid overflowing from the upper end of the cylinder Was again circulated down the cylinder. After the elastic layer roller 1 is immersed in the cylinder at a penetration speed of 100 mm / s and stopped for 10 seconds, the elastic layer roller 1 is pulled up under conditions of an initial speed of 300 mm / s and an final speed of 200 mm / s for 60 minutes. Let dry naturally.

  Next, the raw material of the intermediate layer was cured by heat treatment at 150 ° C. for 2 hours to form an intermediate layer having a thickness of 2 μm, and the elastic roller 1 with the intermediate layer (1) was obtained.

  Subsequently, a surface layer was formed on the elastic roller 1 with the intermediate layer (1) to produce a developing roller 1. The elastic roller 1 with the intermediate layer (1) was installed in the plasma CVD apparatus shown in FIG. Thereafter, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 3 sccm of hexamethylsiloxane vapor was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was set to 2 Pa.

  After the pressure became constant, power with a frequency of 13.56 MHz and 200 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 with the intermediate layer (1) installed in the vacuum chamber was rotated at 24 rpm and treated for 50 seconds. After the processing, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, air was introduced into the vacuum chamber until atmospheric pressure was reached, a surface layer was formed, and the developing roller 1 was obtained.

[Examples 2 to 69, Comparative Examples 1 to 17, 19 to 23] Preparation of developing rollers 2 to 86 and 88 to 92 Elastic layer roller, intermediate layer forming coating liquid, elasticity immersed in the intermediate layer forming coating The developing rollers 2 to 86 are the same as in Example 1 except that the pulling speed of the layer roller, the raw material for preparing the surface layer, and the plasma CVD processing conditions are changed as shown in Tables 2-1, 2-2, and 2-3. 88-92 were prepared. In the table, HMS represents hexamethylsiloxane, TMDS represents 1,1,3,3-tetramethyldisiloxane, and Ar represents argon.

  For the developing rollers 58, 59, 62, 63, 66, and 67, in the preparation of the intermediate layer, the elastic layer roller was immersed in the intermediate layer forming coating material as follows. The elastic layer roller immersed in the coating material for forming the intermediate layer is pulled up at the speed shown in the table, and after naturally drying for 120 minutes, dip coating is performed again, and heat treatment is performed at 150 ° C. for 2 hours. Was repeated once, and dip coating was performed four times in total, and then heated at 150 ° C. for 2 hours.

[Comparative Examples 18 to 20] Preparation of developing rollers 87 to 89 Methyl ethyl ketone prepared by adjusting a thermosetting silicone adhesive sealant (trade name TSE3251-C; manufactured by Momentive Performance Materials) to a concentration of 5% in terms of solid content A mixed solution as a main solvent was prepared. To this mixed solution, carbon black (trade name: Denka Black powder product; manufactured by Denki Kagaku Kogyo Co., Ltd.) is added in an amount of 21 parts by mass with respect to the resin component, and sufficiently stirred to prepare a coating solution for forming the surface layer. did.

  This coating solution was applied to the elastic rollers 1 to 3 with the intermediate layer (1) subjected to surface treatment with excimer light instead of the plasma CVD treatment, using the dip coating method. Further, thereafter, developing rollers 87 to 89 were produced in the same manner as in Example 1 except that the surface layer was formed by heat treatment at 140 ° C. for 2 hours.

[Development roller physical property evaluation]
When the abundance ratio O / Si and the abundance ratio C / Si were determined on the surface of the developing roller 1 obtained with an X-ray photoelectron spectrometer, they were 0.65 and 0.05, respectively. Moreover, when the film thickness of the surface layer of the developing roller was measured using a thin film measuring apparatus (trade name: F20-EXR; manufactured by FILMETRICS), the film thickness was 250 nm. The measurement was performed at a total of nine places, that is, three places equally divided in the longitudinal direction of the developing roller and three places equally divided in the circumferential direction, and the arithmetic average value of the obtained values was taken as the film thickness.

  Further, the measurement roller was cut out to a size of 1 mm until the developing roller reached the core with a razor, and the thickness of the intermediate layer was measured to find that the thickness of the intermediate layer was 2 μm. For the measurement, observation was performed using a digital microscope (trade name: VH-2450: Keyence Corporation). As with the film thickness of the surface layer, the measurement was performed at a total of nine locations, that is, three locations equally divided in the longitudinal direction of the developing roller and three locations equally divided in the circumferential direction. It was.

Furthermore, when the composite elastic modulus of the elastic layer and the intermediate layer of the developing roller 1 was measured in an environment of a temperature of 23 ° C. and a humidity of 50% RH, they were 0.5 MPa and 50 MPa, respectively. Sample of composite elastic modulus of the elastic layer (Ere), as cross section shown in FIG. 3 is measuring unit, after cutting the elastic layer, produced by fixing to a support, a measurement area is 4 mm ² It was. In addition, the composite elastic modulus (Erm) measurement sample of the elastic layer of the intermediate layer was cut into an intermediate layer and embedded in a resin so that the cross section shown in FIG. It was prepared by ultra-precision cutting and adjusting the cross section, and the measurement area was 1 μm ² .

Further, the Asker C hardness of the developing roller (1) in the same environment was 52 degrees. Furthermore, when the center line average roughness Ra of the developing roller 1 was measured, Ra was 1.5 μm. For both Asker C hardness and centerline roughness Ra, measurement was performed at a total of nine locations, ie, three locations equally divided in the longitudinal direction of the developing roller and three locations equally divided in the circumferential direction. Was measured. The developing rollers 2 to 92 of Examples 2 to 69 and Comparative Examples 1 to 23 were also evaluated in the same manner. The results are shown in Tables 3-1 to 3-3.
[Image evaluation]
The obtained developing roller was subjected to image evaluation by the following method. The results are shown in Tables 3-1 to 3-3. The laser printer used for the evaluation of the front image was obtained by modifying the output speed of the recording medium of a commercially available laser printer (trade name: HP Color LaserJet CP3505dn, manufactured by Hured Packard) to 48 ppm (also called a modified printer). .) Further, the contact pressure and the approach amount of the developing roller to the toner amount regulating blade were adjusted so that the toner carrying amount on the developing roller was 0.40 mg / cm ² .
[Evaluation of initial toner adhesion image]
The developing roller was incorporated into an electrophotographic process cartridge Q6470A (trade name, manufactured by Hured Packard, color: black) (hereinafter referred to as cartridge Q6470A) and left in an environment of a temperature of 40 ° C. and a humidity of 95% RH for 30 days. Thereafter, the developing roller was remounted on the newly prepared cartridge Q6470A, and further left in an environment of a temperature of 30 ° C. and a humidity of 85% RH for 24 hours. After leaving, in the same environment, the cartridge Q6470A was incorporated into a modified printer and 10 solid white images were output. In this solid white image, the image layer harmful effect due to the initial toner fixing during the standing was evaluated according to the following criteria.
A: No image defects such as fogging due to initial toner fixation are observed in the solid white image. B: Image defects such as fogging caused by initial toner fixation are confirmed in the solid white image, but disappear after the initial output of three images.
C: Image defects such as fogging caused by initial toner fixation are confirmed in the solid white image, but disappear in the image output of the initial 4 sheets or more and 10 sheets or less.
D: Image defects such as fogging caused by initial toner fixation are confirmed in the solid white image, and it does not disappear within 10 sheets of the initial solid white image output.

[Evaluation of image streaks due to long-term contact of developing blade under high temperature and high humidity]
After image evaluation of initial fixation, image streaks were evaluated by long-term contact with the developing blade. After the evaluation, three solid black images were output. In this solid black image, image streaks due to the deformation of the developing roller due to contact with the developing blade being left untreated were evaluated according to the following criteria. The developing roller in which the fixing did not disappear in the image evaluation of the initial toner fixing was evaluated after wiping with a cloth soaked with isopropyl alcohol.
A: In a solid black image, almost no image streaks due to deformation of the developing roller can be confirmed.
B: Slight image streaks due to deformation of the developing roller can be confirmed in the solid black image.
C: In the solid black image, the image streaks due to the deformation of the developing roller can be clearly confirmed, but the cartridge is left for 24 hours in a normal temperature and humidity environment (temperature 23 ° C., humidity 50% RH) and solid black is again displayed. When the image is formed, no image streak is recognized.
D: In the solid black image, the image streaks due to the deformation of the developing roller can be clearly confirmed, and the cartridge is left for 24 hours in a normal temperature and humidity environment (temperature 23 ° C., humidity 50% RH), and again a solid black image. Even when formed, image streaks are observed.

[Endurance filming evaluation]
After image streak evaluation by long-term contact with the developing blade in a high-temperature and high-humidity environment, the developing roller was assembled in a new cartridge Q6470A and left in an environment of a temperature of 23 ° C. and a humidity of 50% RH for 48 hours. In the same environment, the cartridge Q6470A was installed in the modified printer and the continuous image output was performed at a printing rate of 1%. Durability fogging was evaluated by measuring the number of output sheets in which fogging exceeding 3% was observed in the solid white portion, and according to the following criteria.

Also, using a reflection densitometer made by Macbeth for every 5000 outputs, the reflectance of the non-printed portion (reference) and the solid white portion of the print range is measured, and the amount of decrease in reflectance (%) relative to the reference is expressed as “fogging”. " Further, when the number of continuous prints exceeded 10,000, the developing roller was incorporated into a new cartridge Q6470A, and continuous filming was evaluated.
A: The fog of 3% or more is not confirmed even when printing 20000 sheets by continuous printing.
B: Fog of 3% or more was confirmed on 15000 sheets or more and less than 20000 sheets of continuous printing.
C: Fog of 3% or more was confirmed on continuous printing of 10,000 sheets or more and less than 15,000 sheets.
D: Fog of 3% or more was confirmed on less than 10,000 continuous prints.

[Evaluation of durability peelability]
Simultaneously with the above image evaluation, the surface layer of the developing roller was observed with a digital microscope (trade name: VH-8000; manufactured by Keyence Corporation) for every 5000 image outputs, and the following standards for durability peelability and durability were as follows: It was evaluated with.
A: No peeling of the surface layer was observed after continuous 20000 printing.
B: After the continuous printing of 20000 sheets, slight peeling of the surface layer was observed.
C: Peeling of the surface layer was confirmed on 10000 to less than 20000 continuous prints.
D: Peeling of the surface layer was confirmed on less than 10,000 continuous prints.

DESCRIPTION OF SYMBOLS 1 Developing roller 2 Shaft core body 3 Elastic layer 4 Intermediate layer 5 Surface layer

Claims (8)

A developing roller having a shaft core, and a laminated body provided around the shaft core, in which an elastic layer, an intermediate layer, and a surface layer are stacked in this order,
The surface layer contains an organosiloxane, and the organosiloxane has an abundance ratio (O / Si) of oxygen atoms to silicon atoms forming chemical bonds with silicon atoms of 0.65 or more and 1.95 or less. Abundance ratio (C / Si) of carbon atoms forming a chemical bond with silicon atoms to silicon atoms is 0.05 or more and 1.65 or less,
The elastic layer has a composite elastic modulus (Ere) of 0.5 MPa or more and 20 Mpa or less,
The developing roller, wherein the intermediate layer has a composite elastic modulus (Erm) larger than a composite elastic modulus (Ere) of the elastic layer.   The developing roller according to claim 1, wherein the composite elastic modulus (Erm) of the intermediate layer is 50 MPa or more and 5000 MPa or less.   The developing roller according to claim 1, wherein the intermediate layer has a thickness of 2 μm or more and 100 μm or less.   The developing roller according to claim 1, wherein the Asker C hardness is 50 degrees or more and less than 80 degrees.   The developing roller according to claim 1, wherein the intermediate layer includes polyurethane.   The developing roller according to claim 1, wherein a film thickness of the surface layer is 15 nm or more and 5000 nm or less. An electrophotographic process cartridge that is detachably attached to an electrophotographic image forming apparatus main body,
The electrophotographic process cartridge includes at least a developing roller, a toner regulating member, and a toner container, and the developing roller is the developing roller according to any one of claims 1 to 6. Photo process cartridge.   An electrophotographic image forming apparatus having a photosensitive member and a developing roller disposed in contact with the photosensitive member, wherein the developing roller is the developing roller according to any one of claims 1 to 6. An electrophotographic image forming apparatus.

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