JP5328287B2 - Electrophotographic image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrophotographic image forming apparatus that has a developer carrier including Si-O bond and Si-C bond and suppressing a change in developing performance with time, and that stably forms a high quality electrophotographic image. <P>SOLUTION: The electrophotographic image forming apparatus applies a bias voltage between a photoreceptor and a developing roller and develops an electrostatic latent image with toner. The developing roller includes a surface layer having a predetermined layer thickness. The surface layer is formed from a film of silicon oxide containing a carbon atom chemically bonding with a silicon atom. The total of Si, O, C, and H atoms that are present are 90% or more relative to all atoms. The abundance ratio (O/Si) is 0.65 to 1.95. The abundance ratio (C/Si) in the surface of the surface layer is 0.05 to 0.70. In addition, the surface layer has a predetermined capacitance. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to an electrophotographic image forming apparatus.

  In a conventional printer using an electrophotographic system, a developing device is installed inside, and an image is formed through processes of charging, latent image formation, development, transfer, residual transfer cleaning, and fixing. . The developing device includes an electrophotographic photosensitive member, and includes a cleaning unit, a charging unit, a latent image forming unit, a developing unit, and a transfer unit. The image on the photoconductor formed by this developing device is transferred to a recording material at a transfer portion. Subsequently, the recording material onto which the image has been transferred is conveyed to a fixing unit, heated and pressurized, and discharged as a fixed recorded image. As a printer capable of forming a color image, a color printer that includes a plurality of the developing devices and superimposes a plurality of color images and discharges them as a color image is known.

  Development methods in electrophotography are mainly divided into a one-component development method and a two-component development method. Conventionally, two-component developers have been used to output these full-color images. However, in recent years, a developing device using a one-component developing system is often used for the purpose of reducing the weight and size of the electrophotographic apparatus.

  In the one-component development system, a non-magnetic toner containing no magnetic material and a magnetic toner containing a magnetic material may be used in the toner, but when using for a full color image, the magnetic material is included from the viewpoint of color reproducibility. Non-magnetic single component developers are often used.

As a developing device using a one-component developing method, a jumping developing method developing device is known. In the jumping development method, a developer carrying member having a thin toner layer formed on the surface thereof and the photosensitive drum are opposed to each other with a gap larger than the thickness of the toner layer, and an AC is applied between the developer carrying member and the photosensitive drum. A bias voltage having a voltage component is applied to form an electric field therebetween. Then, development is performed by transferring the toner from the developer carrying member to the photosensitive drum.
Therefore, it is important to control the electrostatic capacity of the surface layer of the developer carrying member used in such a development system in order to further improve the development performance. Specifically, the electrical responsiveness of the developer carrying member can be improved by reducing the capacitance of the surface layer and reducing the time constant τ.
On the other hand, the surface layer plays a role of suppressing wear of the developer carrier that is always in contact with the developer amount regulating blade and the developer supply roller. Therefore, the surface layer is required to have excellent mechanical strength. Patent Document 1 proposes the use of a SiO ₂ thin film as a surface layer having excellent mechanical strength.

Japanese Patent Laid-Open No. 02-32380

When the present inventors examined the invention of Patent Document 1, the surface layer made of the SiO ₂ thin film has a high relative dielectric constant. Therefore, it can be said that it is not necessarily a developer carrier suitable for the jumping development system for the reasons described above. I got the recognition that it was not. In addition, the SiO ₂ thin film includes a strong internal stress depending on the film forming conditions, and cracks resulting from the stress may occur.

In the previous studies, the present inventors have found that a silicon oxide film having a chemical bond of Si—O and Si—C has a lower relative dielectric constant and higher mechanical strength than an SiO ₂ film. In addition, it has been found that since it has good flexibility, it exhibits the characteristic that cracks are unlikely to occur. Therefore, an attempt was made to apply the developer carrier having such a surface layer made of a silicon oxide film to a jumping development system. As a result, although the initial performance is good, a decrease in development performance when the formation of an electrophotographic image is repeated has been found as a new problem. The problem is that the Si—C bond in the silicon oxide film is changed to a Si—O bond by the discharge generated between the photoreceptor and the developer carrying member, and the relative dielectric constant of the surface layer changes over time. We obtained the knowledge that it was caused by the rise.

  Accordingly, an object of the present invention is to provide a developer carrying body that includes Si—O bonds and Si—C bonds and suppresses changes in development performance over time, and stably produces high-quality electrophotographic images. The present invention provides an electrophotographic image forming apparatus that can be formed.

That is, the present invention
A photosensitive member, and a developing roller that carries the developer on the surface and conveys the developer to a developing region of an electrostatic latent image formed on the photosensitive member,
In an electrophotographic image forming apparatus that applies a bias voltage including an alternating voltage between the photoconductor and the developing roller and develops an electrostatic latent image formed on the photoconductor with toner.
The developing roller includes a surface layer having a film thickness of 50 nm or more and 5000 nm or less.
It consists of a silicon oxide film containing carbon atoms that are chemically bonded to silicon atoms,
The total number of existing elements of Si, O, C, and H measured by high-frequency glow discharge luminescence surface analysis is 90% or more with respect to all elements,
The abundance ratio (O / Si) of oxygen atoms forming chemical bonds with silicon atoms to silicon atoms is 0.65 or more and 1.95 or less,
The abundance ratio (C / Si) of carbon atoms chemically bonded to silicon atoms on the surface of the surface layer is from 0.05 to 0.70, and
An electrophotographic image forming apparatus having a capacitance of 0.10 pF to 10.0 pF.

  The present invention provides an electrophotographic image forming apparatus capable of suppressing the occurrence of filming because the surface layer can achieve high durability and high adhesion and is excellent in toner releasability. I can do it.

  Further, since the developing roller having a low electrostatic capacity is provided, it is possible to provide an electrophotographic image forming apparatus that is excellent in electrical responsiveness and capable of obtaining a high-quality image.

  Furthermore, since it is excellent in corona resistance, it is possible to provide an electrophotographic image forming apparatus excellent in image characteristics even when used for a long time.

  Hereinafter, although the form of this invention is demonstrated, this invention is not limited by this.

  The electrophotographic image forming apparatus according to the present invention includes a photoconductor and a developing roller that carries a developer on the surface and conveys the developer to a developing area of an electrostatic latent image formed on the photoconductor. A bias voltage including an alternating voltage is applied between the photoconductor and the developing roller, and the electrostatic latent image formed on the photoconductor is developed with toner.

  1 and 2 are cross-sectional views for explaining a configuration example of the developing roller in the present invention.

  As shown in FIG. 1, the developing roller of the present invention can be configured to have a shaft core body 11 formed of a conductive material such as metal, and a surface layer 13 on the outer peripheral surface of the shaft core body 11. . Alternatively, as shown in FIG. 2, a shaft core 11 made of a conductive material such as a metal, an elastic layer 12 on the outer peripheral surface of the shaft core 11, and a surface layer 13 on the outer peripheral surface of the elastic layer 12. It can be set as the structure which has these.

(Shaft core)
The shaft core may be columnar or hollow cylindrical, or may be formed of a conductive material other than metal.

  The developing roller is generally used with an electrical bias applied or grounded. Therefore, the shaft core body is a support member, and it is necessary that at least the surface of the shaft body has conductivity as a conductive material. The material of the shaft core is not particularly limited as long as it has sufficient conductivity to apply a predetermined voltage to the elastic layer or the surface layer. For example, a metal or alloy such as Al, Cu alloy, SUS, or iron or synthetic resin plated with Cr or Ni can be used. In a developing roller used in an electrophotographic image forming apparatus, it is usually appropriate that the shaft core has an outer diameter of Φ4 mm to Φ10 mm.

(Elastic layer)
As described above, the developing roller according to the present invention can be configured to have an elastic layer.

  The elastic layer is a molded body using rubber or resin as a raw material main component. That is, the material of the elastic layer (hereinafter referred to as elastic layer material) contains rubber or resin as a main component.

  Various rubbers can be used as the rubber that can be the main component. 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, butadiene rubber (BR), NBR hydride, polysulfide rubber, urethane rubber.

  Resins that can be the main component are mainly thermoplastic resins. Specific examples include the following.

  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 resins; polycarbonate resins; polystyrene resins ABS resin; Polyester resin such as polyethylene terephthalate and polybutylene terephthalate; Fluororesin; Polyamide resin such as polyamide 6, polyamide 66, MXD6;

  And these rubber | gum and resin can be used individually or in mixture of 2 or more types.

  Furthermore, in the developing roller of the present invention, components such as a conductive agent and a non-conductive filler necessary for the function required for the elastic layer itself can be appropriately blended in the elastic layer material. Further, various additive components used when forming a rubber or resin molded body, for example, a crosslinking agent, a catalyst, a dispersion accelerator and the like can be appropriately blended in the elastic layer 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.

  Examples of the conductive agent based on the electronic conductive mechanism include the following.

  Carbon-based materials such as carbon black and graphite; metals or alloys such as aluminum, silver, gold, tin-lead alloys, copper-nickel alloys; zinc oxide, titanium oxide, aluminum oxide, tin oxide, antimony oxide, indium oxide or oxide Conductive metal oxides obtained by surface treatment of particles such as silver; substances obtained by conducting surface treatment with copper, nickel or silver on various fillers.

  Moreover, the following are mentioned as an example of the electroconductivity imparting agent by an ion conduction mechanism.

_{LiCF 3 SO 3, NaClO 4,} LaClO 4, LiAsF 6, LiBF 4, NaSCN, KSCN, Group 1 metal salts periodic table, such as _{NaCl; NH 4 Cl, (NH} 4) 2 SO 4, NH 4 NO 3 Ammonium salts such as: salts of Group 2 metals of the periodic table such as Ca (ClO ₄ ) ₂ , Ba (ClO ₄ ) ₂ ; these salts and 1,4-butanediol, ethylene glycol, polyethylene glycol, propylene glycol, Complexes of polyhydric alcohols such as polypropylene glycol and their derivatives; complexes of these salts with monools such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, polyethylene glycol monomethyl ether, polyethylene glycol monoethyl ether; Cations such as quaternary ammonium salts Anionic surfactants such as aliphatic sulfonates, alkyl sulfates and alkyl phosphates; amphoteric surfactants such as betaines.

  These conductive agents can be used alone or in admixture of two or more.

  Among these conductive agents, carbon black-based conductive agents are suitable because they can be obtained relatively inexpensively and easily, and good conductivity can be imparted regardless of the type of main component rubber or resin material. is there. As a means for dispersing the fine powdered conductive agent in the elastic layer material, a conventionally used means such as a roll kneader, a Banbury mixer, or a twin screw extruder may be appropriately selected and used.

  Examples of the filler and extender include the following.

  Silica, quartz fine powder, diatomaceous earth, zinc oxide, basic magnesium carbonate, activated calcium carbonate, magnesium silicate, aluminum silicate, titanium dioxide, talc, mica powder, aluminum sulfate, calcium sulfate, barium sulfate, glass fiber, organic Reinforcing agent, organic filler.

  These fillers may be hydrophobized by treating the surface with an organosilicon compound.

  Antioxidants are used for polymer compounds such as hindered phenolic antioxidants, phenolic antioxidants, phosphorus antioxidants, amine antioxidants, sulfur antioxidants, and the like. Any known one can be selected and used.

  A known material can be used as the processing aid. Specific examples include fatty acids such as stearic acid and oleic acid, and metal salts and esters of fatty acids.

  For example, when the elastic layer is made of silicone rubber as a main component, liquid silicone rubber is used as a main component, polyorganohydrogensiloxane is used as a cross-linking component, and a platinum-based catalyst is used to cross-link rubber components. it can.

  The elastic layer can be formed by a conventionally known extrusion molding method or injection molding method, and is not particularly limited. If it has the characteristic described in this invention, it will not specifically limit, For example, an elastic layer can also be set as the structure of two or more layers.

(Surface layer)
The surface layer 13 satisfies the following requirements (1) to (6).
(1) It consists of a silicon oxide film containing a carbon atom having a chemical bond with a silicon atom.
(2) The total number of existing elements of Si, O, C, and H measured by the high-frequency glow discharge luminescence surface analysis method is 90% or more with respect to all elements.
(3) The abundance ratio (O / Si) chemically bonded to the silicon atom is 0.65 or more and 1.95 or less.
(4) The abundance ratio (C / Si) of carbon atoms chemically bonded to silicon atoms on the surface is from 0.05 to 0.70.
(5) It has a capacitance of 0.10 pF to 10.0 pF.
(6) The film thickness is 50 nm or more and 5000 nm or less.

  Hereinafter, each requirement will be sequentially described.

  (1) It is assumed that the surface layer 13 is made of a silicon oxide film containing carbon atoms chemically bonded to silicon atoms. Thereby, the surface layer 13 is excellent in mechanical strength, has sufficient flexibility, and can have a capacitance that can be suitably used for jumping development.

(2) [Number of existing elements with respect to the total number of elements]
The silicon oxide film constituting the surface layer 13 has an abundance ratio of Si, O, C and H of 90.00% or more with respect to all elements.

  In addition, the number of existing elements of Si, O, C, and H contained in the surface layer can be obtained using the following measuring device.

  The abundance ratio of all elements including light elements is measured using a glow discharge emission spectrometer “GD-PROFILER 2 type GD-OES” (trade name, manufactured by Horiba, Ltd.).

Specifically, measurement can be performed under the following measurement conditions.
Measurement mode: Pulse sputtering Anode diameter (analysis area): Diameter φ4mm
Discharge power: 35W
Ar gas pressure: 600 Pa

(3), (4) [(O / Si), (C / Si)]
The abundance ratio (O / Si) of oxygen atoms chemically bonded to silicon atoms in the silicon oxide film constituting the surface layer 13 to silicon atoms is 0.65 or more and 1 over the entire thickness direction of the surface layer 13. .95 or less.

  When (O / Si) is within the above numerical range, the silicon oxide film has a sufficient amount of siloxane bonds necessary to support the surface layer 13 with practically sufficient wear resistance and flexibility. Because it will be. When (O / Si) is less than 0.65, the surface layer 13 does not have sufficient wear resistance, and the surface is likely to be tacky (adhesive). When used as a developing roller, In some cases, the releasability to toner is lowered and filming is likely to occur. On the other hand, when (O / Si) exceeds 1.95, the silicon oxide film itself becomes hard and cracks are likely to occur.

  In the present invention, the surface layer has an abundance ratio (C / Si) of carbon atoms forming a chemical bond with silicon atoms to silicon atoms of 0.05 to 0.70. Moreover, it is preferable that they are 0.05 or more and 0.30 or less.

  When the abundance ratio (C / Si) on the surface of the surface layer 13 is greater than 0.70, the electric resistance value of the developing roller greatly fluctuates when used for a long time, and the image density is different between the start of use and the end of the developing device life. It can be very different. This is because, in the jumping development method, due to a discharge phenomenon that occurs between the developing roller and the electrophotographic photosensitive member, the Si—C bond having a low binding energy is easily cut off, and other elements (mainly hydrogen and oxygen) are regenerated. It is thought that it is due to the bonding and the composition changing. If C / Si is less than 0.05, the film becomes hard and cracks are likely to occur in the surface layer due to pressure contact with a pressure contact member such as a toner regulating member. Further, when the surface layer is formed on the elastic layer, the low molecular weight substance contained in the elastic layer is oozed out, which causes the pressure contact member to be contaminated. The leakage of the low molecular weight substance contaminates the pressure contact member and causes the toner to adhere to the contaminated part. Further, the filming causes toner adhesion (fogging) to the non-printing part and density unevenness in the printing part. It tends to occur.

[Chemical bonding state and abundance ratio]
The abundance ratio of oxygen atoms and carbon atoms to silicon atoms and the chemical bonding state of silicon atoms were determined using the following measuring apparatus.

  The X-ray photoelectron spectrometer “Quantum 2000” (trade name, manufactured by ULVAC-PHI Co., Ltd.) can measure the atomic ratio of all elements except light elements by X-ray photoelectron spectroscopy. Therefore, the peak due to the binding energy of the silicon 2p orbital and oxygen and carbon 1s orbitals on the surface of the surface layer of the developing roller is measured with AlKα as the X-ray source. The chemical bond state and abundance ratio (O / Si) and (C / Si) of each atom are determined from each peak.

  Here, in the chemical bond state obtained from the silicon and carbon peaks, only the bond with silicon was confirmed as the chemical bond state of carbon.

  As for oxygen, the film itself is formed as silicon oxide, so oxygen exists in a state of being bonded to silicon.

  The glow discharge emission spectrometer and the X-ray photoelectron spectrometer can perform measurement at a desired depth because the surface layer can be measured by sputtering the surface layer with Ar plasma.

(5) [Capacitance]
The capacitance of the surface layer is 0.10 pF or more and 10.0 pF or less. If the capacitance is greater than 10.0 pF, image unevenness due to a decrease in toner followability tends to occur. This is because the time constant of the developing roller increases as the capacitance of the surface layer increases, so that the response of the developing bias in which a DC voltage and an AC voltage are superimposed between the developing roller and the photosensitive member is reduced. Conceivable.

  Regarding this phenomenon, the change in the current value when a DC voltage of 50 V is applied to the developing roller is shown in FIG. As means for solving this problem, it is possible to reduce the capacitance of the surface layer even if the film thickness is the same by reducing the relative dielectric constant of the surface layer. The relative dielectric constant of the surface layer can be adjusted by the abundance ratio (C / Si) of carbon atoms having chemical bonds with silicon atoms in the surface layer to silicon atoms. That is, the relative dielectric constant of the surface layer can be reduced by increasing the value of (C / Si). By the way, the relative dielectric constant of the silicon oxide film in which the value of (C / Si) of the surface layer is 0.05 or more and 0.70 or less over the entire thickness is approximately 2.5 to 3.5. A relatively large value. Therefore, it is difficult to set the capacitance of the surface layer to 0.10 pF or more and 10.0 pF. Therefore, in order to set the surface layer surface capacitance (C / Si) to 0.05 to 0.70 and the surface layer capacitance to 0.10 pF to 10.0 pF, the depth of the surface layer It is preferable to incline so that the value of (C / Si) increases in the vertical direction. That is, in view of the long-term electrical stability of the developing roller and the electrostatic capacity of the surface layer, the silicon oxide film has an abundance ratio of carbon atoms to silicon atoms (C) so that the upper layer side (surface side) is electrically stable. / Si) is lowered. On the other hand, the lower layer side increases the abundance ratio (C / Si) of carbon atoms to silicon atoms. In this way, it is preferable that the capacitance of the silicon oxide film be within the above range.

In order to adjust the capacitance by increasing (C / Si) in the silicon oxide film in the thickness direction from the surface, for example, the following method may be mentioned. That is, when a silicon oxide film is formed by the plasma CVD method, the ratio of oxygen gas in the mixed gas of hexamethyldisiloxane and oxygen gas introduced into the chamber is adjusted to be low at the initial stage of film formation. Thereafter, the ratio of oxygen gas in the mixed gas is increased.
The degree of inclination of (C / Si) in the silicon oxide film is appropriately determined so that the capacitance of the silicon oxide film is not less than 0.10 pF and not more than 10.0 pF according to the thickness of the silicon oxide film. Adjust it. The value of (C / Si) can also be adjusted by appropriately introducing toluene gas.

  In the examples described later, the electrostatic capacity of the surface layer is measured by attaching the developing roller to the measuring device having the configuration shown in FIG. 4 and contacting the metal roller without rotating the developing roller. Each 90 ° was brought into contact with a metal roller and measured at four points. In addition, the average value of 4 points | pieces was made into the electrostatic capacitance of the surface layer in this invention on the conditions of applied voltage 3V and measurement frequency 0.1Hz or more and 1MHz or less.

In FIG. 4, 1 is a developing roller, 402 is a cylindrical electrode (metal roller), and 403 is a dielectric constant measuring system (using a 1296 type dielectric constant measuring interface and 1260 type impedance analyzer manufactured by Solartron, UK). is there.
(6) [Layer thickness]
The layer thickness of the surface layer is 50 nm or more and 5000 nm or less. The layer thickness of the surface layer is more preferably 300 nm or more and 3000 nm or less. When the thickness of the surface layer is less than 50 nm, it is not possible to obtain a thickness effective for scraping when the developing roller is used. If the layer thickness exceeds 5000 nm, a considerable time is required for production, and the temperature of the elastic layer rises during the production, and the elastic layer may not be able to maintain the shape during molding with a material having a low melting point such as a thermoplastic resin. Therefore, when used as a developing roller, density unevenness tends to occur in the obtained image.

  The thickness of the surface layer is determined by using a thin film measuring apparatus “F20-EXR” (trade name, 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 total of nine places are measured and the average value of the obtained values. Note that the measurement was performed with the refractive index of the silicon oxide film containing carbon at the time of measurement set to 1.42.

  The surface layer according to the present invention may contain other elements in addition to the above-described elements, and more preferably contains nitrogen and / or fluorine from the viewpoint of film stability.

  Examples of the method for forming the surface layer include the following.

  Wet coating methods such as dip coating, spray coating, roll coating, ring coating; physical vapor deposition (PVD) method of vacuum deposition, sputtering, ion plating; chemical vapor phase such as plasma CVD, thermal CVD, laser CVD Growth (CVD) method.

  Among these, the plasma CVD method is more suitable in consideration of the high adhesion between the elastic layer and the surface layer (silicon oxide film), considering the shortening of the processing time, the low processing temperature, the simplicity of the apparatus, and the uniformity of the surface layer to be obtained. preferable.

  Below, an example of the formation method of the surface layer by plasma CVD method is shown.

  FIG. 5 is a schematic view of an apparatus for forming a surface layer by this plasma CVD method.

  The apparatus includes a vacuum chamber 41, a flat plate electrode 42, a raw material gas cylinder and a raw material liquid tank 43, a raw material supply means 44, a gas exhaust means 45 in the chamber, a high frequency supply power supply 46 for supplying a high frequency, and an elastic roller 48. The motor 47 is configured to rotate the motor.

  Using the apparatus shown in FIG. 3, a developing roller having a silicon oxide film containing carbon can be manufactured by the following procedure.

  Procedure (1) A shaft core body or an elastic roller 48 having an elastic layer formed on the shaft core body is placed between the flat plate electrodes 42, and the motor 47 is made uniform so that the resulting silicon oxide film containing carbon is uniform. Is driven to rotate in the circumferential direction.

  Procedure (2) The inside of the vacuum chamber 41 is set to 1 Pa or less by the exhaust means.

  Procedure (3) A raw material gas is introduced from the raw material gas introduction port, high frequency power is supplied to the flat plate electrode 42 by a high frequency power supply 46, plasma is generated, and film formation is performed.

  Procedure (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 41 to the atmospheric pressure, and the shaft core or the elastic roller 48 is taken out.

  It is possible to produce a developing roller having a silicon oxide film containing carbon by the procedure as described above. Note that a large number of shaft cores or elastic rollers 48 subjected to plasma CVD processing may be processed simultaneously as long as they can be placed in a uniform plasma atmosphere.

  Here, as the raw material gas, a gaseous or gasified 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 organosilicon compound include the following.

  1,1,3,3-tetramethyldisiloxane, hexamethyldisiloxane, hexamethyldisilazane, 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 or the like 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. Further, vaporization may be promoted in a reduced pressure state of the raw material.

A nitrogen-containing gas (N ₂ O, N ₂ , ammonia) or an oxygen-containing gas (oxygen, CO ₂ , CO) may be introduced into the vacuum chamber together with or in addition to the source gas. Is possible. In addition, examples of the inert gas that can be used include gases such as helium and argon.

  The abundance ratio of Si, O, C, and H in the surface layer can be controlled by the mixing ratio of the raw material gas to be introduced, the flow rate at the time of introduction, and the supplied high frequency power.

  In order to produce a surface layer by a wet method, a mixture of an inorganic polymer precursor solution and a polymer solution having a hydroxyl group is uniformly applied on the elastic layer, and then a curing means such as heating or ultraviolet irradiation is applied. can do.

  Here, before applying the raw material mixture of the surface layer onto the elastic layer, activation such as ultraviolet irradiation, electron beam irradiation, or plasma treatment is performed so that the mixture can be successfully applied to the shaft core or the elastic layer surface. Processing may be performed.

  The developing roller of the present invention is useful as a developing roller for an image forming apparatus such as a copying machine, a facsimile machine, or a printer, and as a developing roller for a process cartridge in an image forming apparatus of a process cartridge type.

  An example of a developing device equipped with the developing roller of the present invention is schematically shown in FIG. This will be described below with reference to FIG.

  In FIG. 6, an electrophotographic photosensitive member 2 as an electrostatic latent image carrier that carries an electrostatic latent image formed by a known process is rotated in the direction of arrow B. In the hopper 3 which is a toner container, a stirring blade 5 for stirring the nonmagnetic one-component toner 4 is provided.

  A toner supply / peeling member 6 for supplying the toner 4 to the developing roller 1 and stripping off the toner 4 existing on the surface of the developing roller 1 after development is in contact with the developing roller 1. When the supply / peeling roller 6 as a toner supply / peeling member rotates in the same direction as the developing roller 1 (arrow C direction), the surface of the toner supply / peeling roller 6 is counter to the surface of the developing roller 1 in the counter direction. Will be moved to. As a result, the one-component nonmagnetic toner having the nonmagnetic toner supplied from the hopper 3 is supplied to the developing roller 1.

  The thickness of the thin layer of the non-magnetic one-component toner 4 formed on the developing roller 1 is preferably thinner than the closest distance in the developing region D between the developing roller 1 and the photoreceptor 2 in the developing portion. A developing bias voltage is applied to the developing roller 1 by a developing bias power source 7 in order to cause the one-component nonmagnetic toner 4 having the nonmagnetic toner carried thereon to fly. In the present invention, in order to increase the density of the developed image or to improve the gradation, an alternating bias voltage is applied to the developing roller 1 to form an oscillating electric field whose direction is alternately reversed in the developing portion. . In this case, it is preferable that an alternating bias voltage on which a DC voltage component having a value between the potential of the image portion and the background portion is superimposed is applied to the developing roller 1.

  As a waveform of the AC voltage, a sine wave, a rectangular wave, a triangular wave or the like can be used as appropriate. Further, it may be a pulse wave formed by periodically turning on / off a DC power source. In this way, a bias that periodically changes the voltage value can be used as the waveform of the AC voltage.

  The closest distance between the surfaces of the developing roller 1 and the photoreceptor 2 in the developing unit of the developing device is preferably 50 to 400 μm, more preferably 120 μm to 180 μm. The closest distance is a distance at which the distance between the surface layer formed on the surface of the developer roller and the photoconductor is approximately the minimum value. When the closest distance is less than 50 μm, there is a tendency that white-out images are likely to occur due to a developing bias leak. Further, when the closest distance exceeds 400 μm, the followability of the toner with respect to the latent image on the photosensitive member tends to be reduced, so that the image quality may be deteriorated such as a decrease in resolution and a decrease in image density. There is. Therefore, by controlling the closest distance within this range, it is possible to suppress the leakage of the developing bias, improve the followability of the toner to the latent image on the photoreceptor, and obtain high image quality.

Further, the developing device used in the present invention is characterized in that the maximum electric field strength between the developing roller and the photosensitive member is controlled to 5.0 × 10 ⁶ V / m to 1.0 × 10 ⁷ V / m. is there. When the maximum electric field strength is less than 5.0 × 10 ⁶ V / m, the reciprocating motion of the toner is reduced, and scattering and fogging are likely to occur. Furthermore, since the developing power is small, an image having a low image density tends to be obtained. On the other hand, when the maximum electric field strength exceeds 1.0 × 10 ⁷ V / m, image defects such as increased fog due to excessive development force and white spots due to leakage of development bias are likely to occur.

  The toner supply / peeling member 6 is preferably an elastic roller member such as resin, rubber or sponge. As the stripping member, a belt member or a brush member can be used instead of the elastic roller. The toner that has not been transferred to the photosensitive member 2 is once peeled off from the surface of the developing roller by the toner supply / peeling member 6, thereby preventing the generation of stationary toner on the developing roller and making the toner charge uniform. .

  When the supply / peeling roller 6 made of an elastic roller as the toner supply / peeling member is rotated in the counter direction (arrow C direction) with respect to the developing roller 1, the peripheral speed of the roller 6 is determined by the developer carrying member. 20 to 120% is preferable for a peripheral speed of 100%. In particular, 30 to 100% is preferable.

  When the rotation direction on the surface of the supply / peeling roller 6 is the same (forward) direction as the rotation direction of the surface of the developing roller, the peripheral speed of the supply roller is 100 with respect to the peripheral speed of the developing roller in terms of toner supply amount. % To 300% is preferable, and 101% to 200% is more preferable. The rotation direction on the surface of the supply / peeling roller 6 is more preferably rotated in the rotation direction on the surface of the developer carrying member and the counter direction from the viewpoint of stripping property and supply property.

  The amount of penetration of the toner supply / peeling member 6 into the developing roller 1 is preferably 0.5 mm to 2.5 mm from the viewpoint of toner supply and peelability. When the penetration amount of the toner supply / peeling member 9 is less than 0.5 mm, a ghost tends to occur due to insufficient peeling. Further, when the intrusion amount exceeds 2.5 mm, the toner may be damaged, and it tends to cause fusion and fogging due to toner deterioration.

  In the developing device of FIG. 6, as a member for regulating the layer thickness of the non-magnetic one-component toner 4 on the developing roller 1, a material having rubber elasticity such as urethane rubber or silicone rubber, or a metal elasticity such as phosphor bronze or stainless copper. The toner regulating blade 8 made of a material having the above is used.

  A thinner toner layer can be formed on the developing roller 1 by pressing the toner regulating blade 8 against the developing roller 1 in a posture opposite to the rotation direction of the developing roller 1. As the toner regulating blade 8, polyamide elastomer (PAE) is pasted on the surface of a phosphor bronze plate where a stable pressurizing force can be obtained particularly for a stable regulating force and a stable (negative) chargeability to the toner. It is preferable to use a structure. Examples of the polyamide elastomer (PAE) include a copolymer of polyamide and polyether.

  The contact pressure of the toner regulating blade 8 with respect to the developing roller 1 is preferably a linear pressure of 5 g / cm to 50 g / cm from the viewpoint that the regulation of the toner can be stabilized and the toner layer thickness can be suitably adjusted. .

  When the contact pressure of the toner regulating blade 8 is less than the linear pressure of 5 g / cm, the toner regulation tends to be weakened, which may cause fogging or toner leakage. On the other hand, when the linear pressure exceeds 50 g / cm, the damage to the toner tends to increase, which may cause toner deterioration and fusion to the developing roller and blade.

  The developing method is not limited to the so-called jumping developing method as described above, and can be applied to an electrophotographic image forming apparatus in a contact developing method.

  Next, an example of a color electrophotographic image forming apparatus equipped with the developing roller of the present invention is schematically shown in FIG. This will be described below with reference to FIG.

  The color electrophotographic image forming apparatus shown in the schematic diagram of FIG. 7 has a developing device 10 (10a to 10d) provided for each color toner of yellow Y, magenta M, cyan C, and black BK in a tandem format. . Although the specifications of the developing device 10 are slightly different depending on the characteristics of each color toner, the basic configuration is the same. The developing device 10 is provided with a photoreceptor 2 as a latent image carrier that rotates in the direction of the arrow. Around the periphery, a charging member 9 for uniformly charging the photoreceptor 2, exposure means for irradiating the uniformly charged photoreceptor 2 with a laser beam 10 to form an electrostatic latent image, an electrostatic latent image There is provided a hopper 3 for supplying toner to the photoconductor 2 on which the toner is formed and developing the electrostatic latent image. Further, a bias power supply 25 is applied to the toner image on the photoreceptor 2 from the back surface of a recording medium (transfer material) 24 such as paper supplied by a paper feed roller 22 and conveyed by a conveying belt 23 onto the recording medium 24. A transfer member having a transfer roller 26 for transferring is provided. The conveying belt 23 is suspended from the driving roller 27, the driven roller 28, and the tension roller 29, and is synchronized with the image forming unit so that the toner images formed in the respective image forming units are sequentially superimposed and transferred onto the recording medium 24. The recording medium 24 is controlled to move and transport the recording medium 24. The recording medium 24 is electrostatically attracted to the transport belt 23 and transported by the action of the suction roller 30 provided immediately before reaching the transport belt 23.

  In the electrophotographic image forming apparatus of the present invention, the photoconductor 2 and the developing roller 1 are arranged in contact or close to each other, and they rotate in the same direction at the contact or close location of the photoconductor 2 and the developing roller 1. Yes.

  Further, the color electrophotographic image forming apparatus includes a fixing device 31 that fixes the toner image superimposed and transferred onto the recording medium 24 by heating, and a conveying device (not shown) that discharges the image-formed recording medium to the outside of the apparatus. )). The recording medium 24 is peeled off from the conveying belt 23 by the action of the peeling device 32 and sent to the fixing device 31.

  On the other hand, the developing device 10 includes a cleaning member having a cleaning blade 33 that removes transfer residual toner that remains without being transferred onto the photoreceptor 2, and a waste toner container 34 that stores toner scraped off from the photoreceptor. Is provided. The cleaned photosensitive member 2 is on standby when an image can be formed.

  The developing device 10 can be a detachable process cartridge.

  EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated more concretely, this invention is not limited by this.

  The reagents used have a purity of 99.5% or more unless otherwise specified.

1) Rubber raw material for elastic layer and liquid silicone rubber: dimethylpolysiloxane having vinyl groups at both ends (vinyl group content 0.15% by mass) and dimethylsiloxane-methylhydrogensiloxane copolymer having both ends Si-H groups ( An H content of 0.30% bonded to Si atoms was used. In addition, the complex (0.5 mass%) of chloroplatinic acid and divinyltetramethyldisiloxane was used as a curing catalyst.
・ Olefin elastomer "Santoprene 8211-25" (trade name, manufactured by AES Japan Co., Ltd.)
・ Olefin elastomer "Santoprene 8211-45" (trade name, manufactured by AES Japan Co., Ltd.)
・ LDPE "Novatech LD LJ902" (trade name, manufactured by Nippon Polyethylene Corporation)
・ LDPE "NOVATEC LD LJ802" (trade name, manufactured by Nippon Polyethylene Corporation)
-EVA "Evaflex EV45LX" (trade name, manufactured by Mitsui DuPont Polychemical Co., Ltd.)

2) Other components for elastic layer, quartz powder “Min-USil” (trade name, manufactured by Pennsylvania Glass Sand)
・ Carbon black “Denka Black” (trade name, manufactured by Denki Kagaku Kogyo Co., Ltd., powdered product)
MT carbon black “Thermax Flow Foam N990” (trade name, manufactured by CANCAB)

Production Example 1 (Manufacture of elastic roller 1)
100 parts by mass of dimethylpolysiloxane having vinyl groups at both ends (vinyl group content 0.15% by mass), 7 parts by mass of quartz powder “Min-USil” (trade name) and carbon black “Denka Black” (product) Name) 10 parts by mass were blended. This blend was mixed and defoamed using a planetary mixer to obtain a liquid silicone rubber base material. To this base material, 0.5 part by mass of a complex of chloroplatinic acid and divinyltetramethyldisiloxane was blended as a curing catalyst to prepare a solution A. Also, 1.5 parts by mass of a dimethylsiloxane-methylhydrogensiloxane copolymer having both Si-H groups at both ends (H content of 0.30% bonded to Si atoms) is blended with the base material, did.

  On the other hand, a SUM material columnar shaft core having a diameter of 6 mm and a length of 250 mm arranged at the center of a cylindrical mold was prepared. A mixture of the A and B liquids mixed at a mass ratio of 1: 1 by a static mixer was poured into the mold, and the mold was heat-cured at a temperature of 130 ° C. for 20 minutes for demolding. Furthermore, it heated at 200 degreeC for 4 hours, and obtained the elastic roller 1 which has an elastic layer of length 240mm and thickness 3mm.

Production Example 2 (Manufacture of elastic roller 2)
The following materials were pelletized with a twin screw extruder having a diameter of 30 mm and L / D32 to obtain a resin composition.
Polyolefin elastomer “Santoprene 8211-25” (trade name): 100 parts by mass;
MT carbon black “Thermax Flow Foam N990” (trade name): 40 parts by mass.
This resin composition was subjected to crosshead extrusion molding to form a resin layer on the shaft core (the same as that used in Production Example 1). The edge part of this resin layer was cut | disconnected, and also the resin layer part was grind | polished with the rotating grindstone, and the elastic roller 2 which has a 3 mm-thick elastic layer was obtained.

Production Example 3 (Production of elastic roller 3)
The elastic roller 3 was obtained in the same manner as in Production Example 2 except that the olefin elastomer “Santoprene 8211-45” (trade name) was used instead of the polyolefin elastomer “Santoprene 8211-25” (trade name).

Production Example 4 (Production of elastic roller 4)
An elastic roller 4 was obtained in the same manner as in Production Example 2 except that LDPE “Novatech LD LJ902” (trade name) was used instead of the polyolefin elastomer “Santoprene 8211-25” (trade name).

Production Example 5 (Production of elastic roller 5)
An elastic roller 5 was obtained in the same manner as in Production Example 2 except that LDPE “Novatech LD LJ802” (trade name) was used instead of the polyolefin elastomer “Santoprene 8211-25” (trade name).

Production Example 6 (Production of elastic roller 6)
An elastic roller 6 was obtained in the same manner as in Production Example 2, except that EVA “Evaflex EV45LX” (trade name) was used instead of 100 parts by mass of the polyolefin-based elastomer “Santoprene 8211-25” (trade name).

Example 1
An aluminum substrate ground to an outer diameter of 12 mmφ was placed in the plasma CVD apparatus shown in FIG. 5, and then the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 30 sccm of oxygen was introduced as a source gas into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 13 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 aluminum substrate 48 placed in the vacuum chamber was rotated at 10 rpm and treated for 550 seconds. Thereafter, a mixed gas of 8 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 53 Pa. From a high frequency power source, electric power with a frequency of 13.56 MHz and 70 W was supplied to the plate electrodes, and plasma was generated between the electrodes. The aluminum substrate placed in the vacuum chamber was rotated at 10 rpm and treated for 150 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  When the layer thickness of the surface layer of the obtained developing roller was measured using a thin film measuring apparatus “F20-EXR” (trade name), the layer thickness was 1508 nm. In addition, the measurement was performed at a total of nine places including three places equally divided in the longitudinal direction of the developing roller and three places equally divided in the circumferential direction, and the average value of the obtained values was defined as the layer thickness. The measurement was performed with the refractive index of the silicon oxide film containing carbon at the time of measurement set to 1.42.

  Next, the total number of Si, O, C, and H existing elements with respect to all the elements on the surface layer of the developing roller was determined by a high-frequency glow discharge luminescence surface analyzer, and found to be 94.7%. Moreover, (O / Si) in the surface of the surface layer calculated | required with the X ray photoelectron spectrometer was 1.48, and (C / Si) was 0.15. Further, (O / Si) at a depth of 1358 nm from the surface of the surface layer was 0.80, and (C / Si) was 1.20.

  The electrostatic capacity of the surface layer of the developing roller was measured by a dielectric constant measurement system (using a 1296 type dielectric constant measurement interface and 1260 type impedance analyzer manufactured by Solartron, UK), and found to be 5.15.

Example 2
The elastic roller 1 of Production Example 1 was processed under the same conditions as in Example 1.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 1358 nm from the surface. The measurement results are shown in Table 1.

Example 3
After the elastic roller 1 of Production Example 1 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethylsiloxane vapor and 30 sccm of oxygen was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 13 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 installed in the vacuum chamber was rotated at 10 rpm and treated for 200 seconds. Thereafter, 3 sccm of hexamethylsiloxane vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 3 Pa. Electric power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 200 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 681 nm from the surface. The measurement results are shown in Table 1.

Example 4
After the elastic roller 1 of Production Example 2 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 20 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 7 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 150 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 250 seconds. Thereafter, 3 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 3 Pa. Electric power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 200 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 285 nm from the surface. The measurement results are shown in Table 1.

Example 5
After the elastic roller 1 of Production Example 2 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 30 sccm of oxygen was introduced as a source gas into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 13 Pa. From a high frequency power source, electric power with a frequency of 13.56 MHz and 200 W was supplied to the plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 900 seconds. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 5 sccm of toluene vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 5 Pa. From the high frequency power source, electric power with a frequency of 13.56 MHz and 150 W was supplied to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 200 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 1635 nm from the surface. The measurement results are shown in Table 1.

Example 6
After the elastic roller 1 of Production Example 3 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 50 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 15 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 30 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 1000 seconds. Thereafter, a mixed gas of 30 sccm of hexamethylsiloxane vapor and 400 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 75 Pa. From a high frequency power source, electric power with a frequency of 13.56 MHz and 200 W was supplied to the plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 400 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 2550 nm from the surface. The measurement results are shown in Table 1.

Example 7
After the elastic roller 1 of Production Example 3 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 20 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 7 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 150 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 500 seconds. Thereafter, a mixed gas of 30 sccm of hexamethyldisiloxane vapor and 400 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 75 Pa. From the high frequency power source, electric power with a frequency of 13.56 MHz and 150 W was supplied to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 900 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 4500 nm from the surface. The measurement results are shown in Table 1.

Example 8
After the elastic roller 1 of Production Example 4 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 30 sccm of hexamethyldisiloxane vapor as a source gas was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 6 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 150 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 750 seconds. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 5 sccm of toluene vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 5 Pa. From the high frequency power source, electric power with a frequency of 13.56 MHz and 150 W was supplied to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 500 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 1500 nm from the surface. The measurement results are shown in Table 1.

Example 9
After the elastic roller 1 of Production Example 4 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 30 sccm of hexamethyldisiloxane vapor as a source gas was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 6 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 150 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 600 seconds. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 57 Pa. From the high frequency power source, electric power with a frequency of 13.56 MHz and 150 W was supplied to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 500 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 2700 nm from the surface. The measurement results are shown in Table 1.

Example 10
After the elastic roller 1 of Production Example 5 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 50 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 15 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 30 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 300 seconds. Thereafter, 3 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 3 Pa. From a high frequency power source, electric power with a frequency of 13.56 MHz and 300 W was supplied to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 300 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep portion of the surface layer are values at a depth of 315 nm from the surface. The measurement results are shown in Table 1.

Example 11
After the elastic roller 1 of Production Example 5 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 50 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 15 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 30 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 500 seconds. Thereafter, a mixed gas of 30 sccm of hexamethyldisiloxane vapor and 400 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 75 Pa. From the high frequency power source, electric power with a frequency of 13.56 MHz and 150 W was supplied to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 100 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep portion of the surface layer are values at a depth of 1200 nm from the surface. The measurement results are shown in Table 1.

Example 12
An aluminum substrate ground to an outer diameter of 12 mmφ was placed in the plasma CVD apparatus shown in FIG. 5, and then the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 30 sccm of oxygen was introduced as a source gas into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 13 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 aluminum substrate placed in the vacuum chamber was rotated at 10 rpm and treated for 225 seconds. Thereafter, a mixed gas of 8 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 53 Pa. From a high frequency power source, electric power with a frequency of 13.56 MHz and 70 W was supplied to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 75 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 596 nm from the surface. The measurement results are shown in Table 1.

Example 13
After the elastic roller 1 of Production Example 2 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 30 sccm of oxygen was introduced as a source gas into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 13 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 30 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 400 seconds. Thereafter, a mixed gas of 10 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 55 Pa. From a high frequency power source, electric power with a frequency of 13.56 MHz and 70 W was supplied to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 100 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 630 nm from the surface. The measurement results are shown in Table 1.

Example 14
After the elastic roller 1 of Production Example 6 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 50 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 15 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 30 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 30 seconds. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 54 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 20 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep portion of the surface layer are values at a depth of 47 nm from the surface. The measurement results are shown in Table 1.

Example 15
After the elastic roller 1 of Production Example 6 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 30 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 6 Pa. After the pressure became constant, power at a frequency of 13.56 MHz and 70 W was supplied from a high-frequency power source to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 120 seconds. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 54 Pa. Electric power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 100 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 261 nm from the surface. The measurement results are shown in Table 1.

Example 16
After the elastic roller 1 of Production Example 1 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 50 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 13 Pa. After the pressure became constant, power at a frequency of 13.56 MHz and 70 W was supplied from a high-frequency power source to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 900 seconds. Thereafter, 3 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 3 Pa. Electric power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 300 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the outermost surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 1440 nm from the surface. The measurement results are shown in Table 1.

Example 17
After the elastic roller 1 of Production Example 2 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 30 sccm of oxygen was introduced as a source gas into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 13 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 installed in the vacuum chamber was rotated at 10 rpm and treated for 300 seconds. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 5 sccm of toluene vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 5 Pa. From the high frequency power source, electric power with a frequency of 13.56 MHz and 150 W was supplied to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 100 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep portion of the surface layer are values at a depth of 570 nm from the surface. The measurement results are shown in Table 1.

Example 18
After the elastic roller 1 of Production Example 3 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 20 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 7 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 150 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 250 seconds. Thereafter, a mixed gas of 30 sccm of hexamethyldisiloxane vapor and 400 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 75 Pa. From the high frequency power source, electric power with a frequency of 13.56 MHz and 150 W was supplied to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 250 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the outermost surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 1350 nm from the surface. The measurement results are shown in Table 1.

Comparative Example 1
MEK (methyl ethyl ketone) was added to a mixed solution in which the following materials were mixed, and the mixture was dispersed with a sand mill for 1 hour.
Polyurethane polyol prepolymer (trade name: Takelac TE5060, manufactured by Mitsui Takeda Chemical Co.): 100 parts by mass
・ Isocyanate (trade name: Coronate 2521, manufactured by Nippon Polyurethane Co., Ltd.): 63 parts by mass,
Carbon black (trade name: MA100, manufactured by Mitsubishi Chemical Corporation): 20 parts by mass
-Urethane particles (trade name: C400, manufactured by Negami Kogyo Co., Ltd.): 20 parts by mass.

  After dispersion, MEK was further added to adjust the solid content in the range of 20% by mass to 30% by mass as a raw material liquid for the surface layer. The elastic roller of Production Example 1 was immersed in the raw material liquid for the surface layer to coat the outer surface uniformly, and then pulled up and dried naturally. Next, the raw material of the coated surface layer was cured by heat treatment at 140 ° C. for 60 minutes to obtain a developing roller on which the surface layer was formed.

  The layer thickness of the surface layer of the developing roller obtained was obtained by taking a cross-sectional sample of the developing roller including the surface layer and observing with a digital microscope “VH-8000” (trade name, manufactured by Keyence Corporation). The layer thickness of the obtained developing roller was 13 μm.

  Further, the electrostatic capacity of the surface layer of the developing roller was measured in the same manner as in Example 1 and found to be 25.0.

Comparative Example 2
After the elastic roller 1 of Production Example 1 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 55 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 3300 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep portion of the surface layer are values at a depth of 4455 nm from the surface. The measurement results are shown in Table 1.

Comparative Example 3
After the elastic roller 1 of Production Example 1 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 50 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 15 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 30 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 600 seconds. Thereafter, 3 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 3 Pa. After the pressure became constant, power at a frequency of 13.56 MHz and 300 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 600 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep portion of the surface layer are values at a depth of 585 nm from the surface. The measurement results are shown in Table 1.

Comparative Example 4
After the elastic roller 1 of Production Example 1 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, 30 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber as a source gas, and the pressure in the vacuum chamber was adjusted to 9 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 120 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 200 seconds. Thereafter, a mixed gas of 10 sccm of hexamethyldisiloxane vapor and 400 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 72 Pa. From a high frequency power source, electric power with a frequency of 13.56 MHz and 200 W was supplied to the plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 200 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 1020 nm from the surface. The measurement results are shown in Table 1.

Comparative Example 5
A perhydropolysilazane solution (trade name: Aquamica NP110-5; manufactured by AZ Electronic Materials Co., Ltd.) was applied to an aluminum substrate ground to an outer diameter of 12 mmφ by a dip method. Then, the developing roller in which the surface layer was formed was obtained by air-drying for one day and night.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 1800 nm from the surface. The measurement results are shown in Table 1.

Comparative Example 6
After the elastic roller 1 of Production Example 6 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 50 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 15 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 30 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 35 seconds. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 54 Pa. After the pressure became constant, power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and processed for 15 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 44 nm from the surface. The measurement results are shown in Table 1.

Comparative Example 7
After the elastic roller 1 of Production Example 2 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 20 sccm of hexamethyldisiloxane vapor and 30 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 9 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 installed in the vacuum chamber was rotated at 10 rpm and treated for 600 seconds. Thereafter, 3 sccm of hexamethyldisiloxane vapor was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 3 Pa. Electric power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 600 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 342 nm from the surface. The measurement results are shown in Table 1.

Comparative Example 8
After the elastic roller 1 of Production Example 3 was installed in the plasma CVD apparatus shown in FIG. 5, the vacuum chamber was depressurized to 1 Pa using a vacuum pump. Thereafter, a mixed gas of 10 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber as a raw material gas, and the pressure in the vacuum chamber was adjusted to 55 Pa. After the pressure became constant, power at a frequency of 13.56 MHz and 70 W was supplied from a high-frequency power source to the flat plate electrodes to generate plasma between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 3000 seconds. Thereafter, a mixed gas of 5 sccm of hexamethyldisiloxane vapor and 300 sccm of oxygen was introduced into the vacuum chamber, and the pressure in the vacuum chamber was adjusted to 54 Pa. Electric power with a frequency of 13.56 MHz and 250 W was supplied from a high-frequency power source to the plate electrodes, and plasma was generated between the electrodes. The elastic roller 1 installed in the vacuum chamber was rotated at 10 rpm and treated for 2700 seconds.

  After the treatment, the power supply was stopped, the raw material gas remaining in the vacuum chamber was exhausted, and air was introduced into the vacuum chamber until atmospheric pressure was reached. Thereafter, the developing roller on which the surface layer was formed was taken out.

  Various physical properties of the surface layer of the obtained developing roller were measured in the same manner as in Example 1.

  Note that (O / Si) and (C / Si) in the deep part of the surface layer are values at a depth of 4545 nm from the surface. The measurement results are shown in Table 1.

<Evaluation of developing rollers according to Examples 1 to 18 and Comparative Examples 1 to 8>
The developing rollers according to Examples 1 to 18 and Comparative Examples 1 to 8 were incorporated as developing rollers in a cartridge for an electrophotographic laser printer (trade name: LBP-5000, manufactured by Canon Inc.). Using this cartridge, the electrostatic latent image was developed with toner in an environment of a temperature of 20 ° C. and a humidity of 50% RH to output an image. Thereafter, the obtained image was evaluated for evaluation items (fogging, density unevenness, character quality, density stability).

  Moreover, the surface of the developing roller after the following evaluation image output was observed, and evaluation items (cracking of the surface layer, presence of filming on the surface layer, and durability of the surface layer) were evaluated. The laser printer “LBP-5000” used here is a machine for A4 vertical output, and has a recording medium output speed of 8 ppm. For image evaluation, an initial solid black image using black BK toner and a halftone with a density of 0.7 measured by “Portable spectral densitometer 504 with special software / firmware” (trade name, manufactured by X-Rite). An image output was used. Further, continuous image formation by 1% printing was performed, and a solid black image and a solid white image were output after 3000 sheets.

(Cover)
The solid white image after 3000 sheets was measured for reflection density with a photovolt reflection densitometer “TC-6DS / A” (trade name, manufactured by Tokyo Denshoku Co., Ltd.), and the difference from the non-printed part was covered (%). And evaluated according to the following criteria.
A: Less than 1.5%.
B: 1.5% or more and less than 3.0%.
C: 3.0% or more.

(Density unevenness in the printed part)
The initial solid black image and the halftone image were visually observed for density unevenness and evaluated according to the following criteria. It should be noted that density unevenness is most visible in a halftone image and relatively easy to see in a solid black image.
A: Any image is not confirmed with the naked eye.
B: Density unevenness is seen on the halftone image, but no density unevenness is seen on the solid black image.
C: Density unevenness is observed in any image.

(Character quality)
A 4-point “electric” character image was output at the initial stage, and the character blurring and scattering were visually evaluated, and the image quality was evaluated according to the following criteria.
A: A clear image that does not scatter even when viewed with a magnifying glass having a magnification of 10 times.
B: Although there is some scattering, there is no practical problem.
C: Character blurring is noticeable in addition to scattering.

(Concentration stability)
The density of the solid black image at the initial stage and after 3000 sheets was measured using “portable spectral densitometer 504 equipped with special software / firmware” (trade name, manufactured by X-Rite) and evaluated according to the following criteria.
A: Each density difference is less than 0.1.
B: Each density difference is 0.1 or more and less than 0.2.
C: Each density difference is 0.2 or more.

(Surface cracks on the surface layer)
The initial solid black image and halftone image were visually checked for the occurrence of streaks due to cracks in the surface layer, and judged according to the following criteria.
A: No streak is generated.
B: Although streaks are observed, there are no streaks due to cracks on the image.
C: Streaks are observed, and there are streaks due to cracks in the image.

(Durability of surface layer)
After the output of all the images for image evaluation, the surface of the developing roller is observed with a digital microscope “VH-8000” (trade name, manufactured by Keyence Corporation) to determine whether the surface layer is peeled off or scraped. Confirmed and judged according to the following criteria.
A: There is no peeling and scraping of the surface layer.
B: Peeling and scraping of the surface layer are slightly observed, but are slight.
C: The surface layer is clearly peeled and scraped.

(Developer roller surface toner fusion-filming)
After the output of all the images for image evaluation, the surface of the developing roller is observed, the toner is fused to the surface of the developing roller, so-called filming occurrence state, and the final evaluation image is observed. It was evaluated with.
A: No filming on the developing roller.
B: There is no problem with the image, and filming slightly occurs on the developing roller.
C: The image is slightly affected by toner adhesion on the developing roller.

  Further, the following characteristic tests were conducted on the developing rollers obtained in the examples and comparative examples.

(Development roller exudation test)
The exuding property of the low molecular weight substance from the elastic body generated when the developing roller is in pressure contact with the toner regulating member was tested as follows.

The developing roller was incorporated into the process cartridge and left for 30 days in an environment of a temperature of 40 ° C. and a humidity of 95% RH while being in pressure contact with the toner regulating member. Thereafter, the process cartridge after being left was incorporated into a laser printer, and a solid black image and a halftone image were output. The first sheet was visually evaluated and the following evaluation was made on the exuding property (whether or not the exudate from the elastic body adhered to the photoconductor caused the occurrence of defects).
A: There is no image defect based on the exudate.
B: Although there is an image defect based on the exudate, there is no image problem.
C: Image defect based on exudate is observed.

  The analysis evaluation results for each developing roller are summarized in Table 1, and the characteristic evaluation results are summarized in Table 2.

It is sectional drawing of an example of a developing roller. It is sectional drawing of an example of a developing roller. FIG. 6 is a diagram showing a change in current value with respect to time when a voltage is applied to the developing roller. It is the schematic explaining the measuring method of the electrostatic capacitance of a surface layer. It is a schematic diagram which shows an example of a plasma CVD apparatus. 1 is a schematic diagram illustrating an embodiment of a developing device of the present invention. 1 is a schematic diagram showing an embodiment of an electrophotographic image forming apparatus of the present invention. .

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Developing roller 2 Photoconductor 3 Hopper 4 Toner 5 Stirring blade 6 Toner supply / peeling member 7 Developing bias power supply 8 Toner regulating blade 9 Charging member 10 Developing devices 10a to 10d (for each color)
11 Shaft Core 12 Elastic Layer 13 Surface Layer 14 Surface Layer 21 Laser Light 22 Feeding Roller 23 Conveying Belt 24 Recording Medium 25 Bias Power Supply 26 Transfer Roller 27 Drive Roller 28 Driven Roller 29 Tension Roller 30 Adsorption Roller 31 Fixing Device 32 Peeling Device 33 Cleaning blade 34 Waste toner container 41 Vacuum chamber 42 Flat electrode 43 Raw material gas cylinder and raw material liquid tank 44 Raw material supply means 45 Exhaust means 46 High frequency supply means 47 Motor 48 Elasticity in which an elastic layer is formed on the shaft core or shaft core Roller 402 Cylindrical electrode (metal roller)
403 Dielectric constant measurement system

Claims (4)

A photosensitive member, and a developing roller that carries the developer on the surface and conveys the developer to a developing region of an electrostatic latent image formed on the photosensitive member,
In an electrophotographic image forming apparatus that applies a bias voltage including an alternating voltage between the photoconductor and the developing roller and develops an electrostatic latent image formed on the photoconductor with toner.
The developing roller includes a surface layer having a film thickness of 50 nm or more and 5000 nm or less.
It consists of a silicon oxide film containing carbon atoms that are chemically bonded to silicon atoms,
The total number of existing elements of Si, O, C, and H measured by high-frequency glow discharge luminescence surface analysis is 90% or more with respect to all elements,
The abundance ratio (O / Si) of oxygen atoms forming chemical bonds with silicon atoms to silicon atoms is 0.65 or more and 1.95 or less,
The abundance ratio (C / Si) of carbon atoms chemically bonded to silicon atoms on the surface of the surface layer is from 0.05 to 0.70, and
An electrophotographic image forming apparatus having a capacitance of 0.10 pF to 10.0 pF.   2. The electrophotographic image forming apparatus according to claim 1, wherein (C / Si) on the surface of the surface layer is 0.05 or more and 0.30 or less.   3. The electrophotographic image forming apparatus according to claim 1, wherein the surface layer has a thickness of 300 nm to 3000 nm. The closest distance between the surface of the developing roller and the photosensitive member is 50 to 400 μm, and the maximum electric field strength between the developing roller and the photosensitive member is 5.0 × 10 ⁶ V / m to 1.0. The electrophotographic image forming apparatus according to claim 1, which is × 10 ⁷ V / m.

Images