JP2008310198A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus satisfactorily preventing the cleaning defect of an intermediate transfer body even when the intermediate transfer body has a hard release layer on its surface. <P>SOLUTION: The image forming apparatus includes the intermediate transfer body which has the hard release layer on its surface, carries a toner image, primarily transferred from a latent image carrier, on the hard release layer, and secondarily transfers the carried toner image to a target body; and a cleaning blade which is disposed in contact with the intermediate transfer body and removes toner remaining on the hard release layer of the intermediate transfer body. The image forming apparatus is characterized in that the surface roughness Rz of the hard release layer is 50 to 100 nm, and the cleaning blade has rebound resilience of 20 to 60% and contacts the intermediate transfer body at a contact angle of 8 to 15° with linear pressure of 25 to 40 N/m. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a monochrome / full-color copying machine, a printer, a FAX, and a complex machine thereof.

  In an intermediate transfer type image forming apparatus, each color toner image formed on a latent image carrier is primarily transferred, superimposed on the intermediate transfer member, and then collectively transferred to a transfer object. In such an image forming apparatus, a small amount of toner remains on the intermediate transfer member during secondary transfer. Therefore, a method of contacting an elastic blade such as rubber is widely used as a cleaning means for removing residual toner.

  In order to improve the secondary transfer rate, it is conceivable to provide a hard release layer on the surface of the intermediate transfer member to improve the releasability with respect to the toner. However, in such an image forming apparatus, although the secondary transfer efficiency is improved, the toner remains on the intermediate transfer member even when the cleaning blade is used, and the cleaning failure cannot be sufficiently prevented. Specifically, since the hard release layer on the surface of the intermediate transfer member is formed to facilitate the separation of the toner, the frictional force with the blade is lower than that of a conventional intermediate transfer member surface that does not have a hard release layer. . For this reason, the edge of the cleaning blade is not drawn in the moving direction of the intermediate transfer member and slips on the surface thereof, resulting in poor cleaning such as slipping through. In particular, when an intermediate transfer member having a hard release layer on the surface is used in combination with a toner having a small particle size and a spherical shape, for example, a polymerized toner, for forming a high-quality image, the occurrence of poor cleaning is remarkable. It was.

On the other hand, from the viewpoint of the cleaning property of the photoreceptor, the surface of the photoreceptor should be 15 to 40 nm with a toner particle diameter of 4 to 10 μm (Patent Document 1), and a blade when using small particle size polymerized toner It has been reported that the rubber hardness, impact resilience, and contact load are regulated (Patent Document 2).
JP 2002-229234 A JP 2002-268490 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that can sufficiently prevent poor cleaning of an intermediate transfer body even when an intermediate transfer body having a hard release layer on the surface thereof is used.

The present invention has a hard release layer on the surface, carries a toner image primarily transferred from a latent image carrier on the hard release layer, and intermediately transfers the carried toner image to a transfer object. A transfer member; and a cleaning blade disposed in contact with the intermediate transfer member to remove toner remaining on the hard release layer of the intermediate transfer member;
An image forming apparatus comprising:
The surface roughness Rz of the hard release layer is 50 to 100 nm,
The present invention relates to an image forming apparatus characterized in that the cleaning blade has a rebound resilience of 20 to 60% and abuts against the intermediate transfer member at a contact angle of 8 to 15 ° and a linear pressure of 25 to 40 N / m.

  According to the image forming apparatus of the present invention, the surface roughness Rz of the hard release layer and the rebound resilience, contact angle, and linear pressure of the cleaning blade are combined and set within predetermined ranges, respectively, so that the surface is hard. Even when an intermediate transfer member having a release layer is used, poor cleaning of the intermediate transfer member can be sufficiently prevented. Moreover, the effect of preventing poor cleaning can be obtained over a long period of time.

  An image forming apparatus according to the present invention bears a toner image that has been primarily transferred from a latent image carrier, and an intermediate transfer member that secondarily transfers the carried toner image to a transfer object, and abutting against the intermediate transfer member A cleaning blade that is disposed and removes toner remaining on the intermediate transfer member is provided. Hereinafter, the image forming apparatus of the present invention will be described with reference to an example of a tandem full-color image forming apparatus having a latent image carrier for each color developing unit that forms a toner image on the latent image carrier. As long as it has a body and a cleaning blade, it may be of other structure, for example, a four-cycle full-color image forming apparatus having a developing section for each color for one latent image carrier.

  FIG. 1 is a schematic configuration diagram of an example of an image forming apparatus of the present invention. In the tandem type full-color image forming apparatus of FIG. 1, each developing unit (1a, 1b, 1c, 1d) usually has at least a charging device, an exposure device, around the latent image carrier (2a, 2b, 2c, 2d). A developing device, a latent image carrier cleaning device (none of which are shown), and the like are arranged. Such developing sections (1a, 1b, 1c, 1d) are arranged in parallel to the intermediate transfer body 3 stretched by at least two stretching rollers (10, 11). The toner images formed on the surface of the latent image carrier (2a, 2b, 2c, 2d) in each developing unit are respectively primary transferred to the intermediate transfer member 3 using primary transfer rollers (4a, 4b, 4c, 4d). Then, a full color image is formed on the intermediate transfer member. The full-color image transferred onto the surface of the intermediate transfer body 3 is secondarily transferred to a transfer object 6 such as paper at once using a secondary transfer roller 5 and then passed through a fixing device (not shown). A full-color image is obtained on the transfer object. On the other hand, the untransferred toner remaining on the intermediate transfer member is removed by the cleaning blade 7.

  The latent image carriers (2a, 2b, 2c, 2d) are so-called photoconductors on which toner images are formed based on electrostatic latent images formed on the surface. The latent image carrier is not particularly limited as long as it can be mounted on a conventional image forming apparatus, and usually an organic photosensitive layer is used.

  In the present invention, the intermediate transfer member 3 has a hard release layer having a surface roughness Rz of 50 to 100 nm, preferably 70 to 100 nm on the surface. If Rz is too small, the frictional force between the belt surface and the blade becomes too large, causing the blade to turn over, resulting in poor cleaning. If Rz is too large, cleaning failure due to slipping occurs.

  In this specification, the surface roughness is the surface roughness Rz at a measurement length of 10 μm measured using an atomic force microscope (AFM), and a value measured by NanoScope (manufactured by Digital Instruments) is used. . An atomic force microscope can measure the shape of an object on the nano-order, and can observe a fine surface shape. A general-purpose surface roughness meter measures undulations and scratches on the surface of an object, but microscopic surface roughness measurement using an atomic force microscope can evaluate the surface properties of the material itself.

  In FIG. 1, an intermediate transfer belt is shown as the intermediate transfer body 3. However, the intermediate transfer belt is not limited to this as long as it has a hard release layer having such a surface roughness Rz on the surface. A so-called intermediate transfer drum may be used.

  Taking the case where the intermediate transfer member 3 has a seamless belt shape as an example, the intermediate transfer member of the present invention will be described in detail. FIG. 2 is a conceptual cross-sectional view showing the layer configuration of the intermediate transfer belt 3.

  The intermediate transfer belt 3 has at least a base material 31 and a hard release layer 32 formed on the surface of the base material 31.

The substrate 31 is not particularly limited, but preferably has a surface resistivity in the range of 10 ⁶ to 10 ¹² Ω / □, and usually has a seamless belt shape. For example, polycarbonate (PC); polyimide (PI); polyphenylene sulfide (PPS); polyamideimide (PAI); polyvinylidene fluoride (PVDF), tetrafluoroethylene-ethylene copolymer (ETFE), and other fluororesins; polyurethane Resin materials such as polyamide resins such as polyamideimide, or ethylene-propylene-diene rubber (EPDM); nitrile-butadiene rubber (NBR); chloroprene rubber (CR); silicone rubber; rubber such as urethane rubber A material in which a conductive filler such as carbon is dispersed or an ionic conductive material is used is used. The thickness of the substrate is usually set to about 50 to 200 μm in the case of a resin material and about 300 to 700 μm in the case of a rubber material.

  The intermediate transfer belt 3 may have another layer between the base material 31 and the hard release layer 32, and the hard release layer 32 is located on the outermost surface layer.

  The base material 31 may be pretreated by a known surface treatment method such as plasma, flame, or ultraviolet irradiation before the hard release layer 32 is laminated.

  The hard release layer 32 has the surface roughness Rz, and is a hard layer that exhibits releasability with respect to the toner. Examples of such a hard release layer include an inorganic oxide layer and a hard carbon-containing layer. The hardness of the hard release layer 32 is usually 3 GPa or more, particularly 3 to 11 GPa. The thickness of the hard release layer is preferably 1 μm or less, more preferably 10 nm or more and 600 nm or less from the viewpoint of preventing cracking or peeling of the layer.

  In the present specification, the hardness is a hardness measured by a nanoindentation method, and a value measured using NANO Indenter XP / DCM (manufactured by MTS Systems / MTS NANO Instruments) is used.

  The surface roughness Rz of the hard release layer can be controlled by adjusting the film thickness in the method for producing the inorganic oxide layer and the hard carbon-containing layer described later. For example, when the film thickness is reduced, Rz increases, and when the film thickness is increased, Rz decreases.

The inorganic oxide layer preferably contains at least one oxide selected from SiO ₂ , Al ₂ O ₃ , ZrO ₂ , and TiO ₂ , and particularly preferably SiO ₂ . The inorganic oxide layer is plasma CVD that deposits and forms a film corresponding to the raw material gas by plasmaizing at least the mixed gas of the discharge gas and the raw material gas of the inorganic oxide layer, particularly plasma performed at or near atmospheric pressure Preferably formed by CVD. The thickness of the inorganic oxide layer is preferably 1 μm or less, particularly preferably 10 to 600 nm.

Hereinafter, taking the case where silicon oxide inorganic oxide layer using (SiO ₂₎ is formed by an atmospheric pressure plasma CVD, the following description will discuss the manufacturing apparatus and manufacturing method. The atmospheric pressure or the pressure in the vicinity thereof is about 20 kPa to 110 kPa, and 93 kPa to 104 kPa is preferable in order to obtain the good effects described in the present invention.

  FIG. 3 is an explanatory view of a manufacturing apparatus for manufacturing an inorganic oxide layer. The inorganic oxide layer manufacturing apparatus 40 forms the inorganic oxide layer on the substrate by a direct method in which the discharge space and the thin film deposition region are substantially the same part, and is deposited and formed by exposing the plasma to the substrate. An atmospheric pressure plasma CVD apparatus that is a film forming apparatus for forming an inorganic oxide layer on the surface of a roll electrode 50 and a driven roller 60 that are wound around an endless belt-shaped base 31 and rotated in the direction of the arrow 70.

  The atmospheric pressure plasma CVD apparatus 70 includes at least one set of fixed electrodes 71 arranged along the outer periphery of the roll electrode 50, a discharge space 73 in a region where the fixed electrode 71 and the roll electrode 50 are opposed to each other, and discharge. A mixed gas supply device 74 that generates a mixed gas G of at least a raw material gas and a discharge gas and supplies the mixed gas G to the discharge space 73; a discharge vessel 79 that reduces the inflow of air into the discharge space 73 and the like; A first power source 75 connected to the fixed electrode 71, a second power source 76 connected to the roll electrode 50, and an exhaust unit 78 that exhausts the used exhaust gas G ′. The second power source 76 may be connected to the fixed electrode 71, and the first power source 75 may be connected to the roll electrode 50.

The mixed gas supply device 74 supplies, to the discharge space 73, a mixed gas obtained by mixing a raw material gas for forming a film containing silicon oxide and a rare gas such as nitrogen gas or argon gas.
The driven roller 60 is urged in the direction of the arrow by the tension urging means 61 and applies a predetermined tension to the base material 31. The tension urging means 61 releases the urging of the tension at the time of changing the base material 31 so that the base material 31 can be easily changed.

  The first power supply 75 outputs a voltage having a frequency ω1, the second power supply 76 outputs a voltage having a frequency ω2 higher than the frequency ω1, and the electric field in which the frequencies ω1 and ω2 are superimposed on the discharge space 73 by these voltages. V is generated. Then, the mixed gas G is turned into plasma by the electric field V, and a film (inorganic oxide layer) corresponding to the raw material gas contained in the mixed gas G is deposited on the surface of the substrate 31.

  As another form, one of the roll electrode 50 and the fixed electrode 71 may be connected to the ground, and the power supply may be connected to the other electrode. In this case, it is preferable to use the second power supply because a dense thin film can be formed. This is particularly preferable when a rare gas such as argon is used as the discharge gas.

  Among the plurality of fixed electrodes, a plurality of fixed electrodes positioned on the downstream side in the rotation direction of the roll electrode and the mixed gas supply device are stacked so that the inorganic oxide layers are stacked, and the thickness of the inorganic oxide layer is adjusted. May be.

  Among the plurality of fixed electrodes, the inorganic electrode layer is deposited with the fixed electrode and the mixed gas supply device located on the most downstream side in the rotation direction of the roll electrode, and with the other fixed electrode and the mixed gas supply device located further upstream, For example, other layers such as an adhesive layer that improves the adhesion between the inorganic oxide layer and the substrate may be formed.

  A gas supply device for supplying a gas such as argon, oxygen, or hydrogen upstream of the fixed electrode for forming the inorganic oxide layer and the mixed gas supply device in order to improve the adhesion between the inorganic oxide layer and the substrate; You may make it activate the surface of a base material by providing a fixed electrode and performing plasma processing.

  Specific examples of the hard carbon-containing layer include, for example, an amorphous carbon film, a hydrogenated amorphous carbon film, a tetrahedral amorphous carbon film, a nitrogen-containing amorphous carbon film, and a metal-containing amorphous carbon film. The thickness of the hard carbon-containing layer is preferably the same as that of the inorganic oxide layer.

  The hard carbon-containing layer can be manufactured by the same method as the manufacturing method of the inorganic oxide layer described above, that is, at least a mixed gas of the discharge gas and the source gas is converted into a plasma to deposit a film according to the source gas. It can be manufactured by plasma CVD to be formed, particularly plasma CVD performed at or near atmospheric pressure.

As a raw material gas for forming the hard carbon-containing layer, a gas or liquid organic compound gas, particularly a hydrocarbon gas, is used at room temperature. The phase state of these raw materials does not necessarily need to be a gas phase at normal temperature and pressure, and can be solid even in a liquid phase as long as it can be vaporized through heating, decompression, or the like by melting, evaporation, sublimation, etc. It can also be used in phases. As for the hydrocarbon gas as the raw material gas, for example, paraffinic hydrocarbons such as CH ₄ , C ₂ H ₆ , C ₃ H ₈ , and C ₄ H ₁₀ , and acetylene carbonization such as C ₂ H ₂ and C ₂ H ₄ are used. Gases containing at least hydrocarbons such as hydrogen, olefinic hydrocarbons, diolefinic hydrocarbons, and aromatic hydrocarbons can be used. Furthermore, compounds other than hydrocarbons can be used as long as they are compounds containing at least a carbon element such as alcohols, ketones, ethers, esters, CO, and CO ₂ .

  The cleaning blade 7 used in the present invention has a rebound resilience of 20 to 60%, preferably 23 to 50%, and a contact angle of 8 to 15 °, preferably 10 to 13 ° with respect to the intermediate transfer body 3. And a linear pressure of 25 to 40 N / m, preferably 28 to 35 N / m. If the rebound resilience is too small, the linear pressure is reduced and cleaning failure occurs. If the impact resilience is too large, chipping and wear of the blade edge increase, resulting in poor cleaning. If the contact angle with respect to the intermediate transfer member is too small, the tip of the blade will hit the belly, resulting in poor cleaning. If the contact angle is too large, the blade edge is pulled too much, leading to chipping of the edge and poor cleaning. If the linear pressure on the intermediate transfer member is too small, the toner slips through the powder pressure of the toner to be cleaned, resulting in poor cleaning. If the linear pressure is too large, chipping of the blade edge or turning of the blade occurs, resulting in poor cleaning.

The impact resilience is the elasticity when subjected to an impact, and a value measured by a method according to JIS-K6255 at 25 ° C. is used.
Rebound resilience can be achieved by selecting the constituent material of the cleaning blade.

The contact angle is a so-called effective contact angle, and is an actual angle formed by the tip of the cleaning blade 7 and the surface of the intermediate transfer member 3. In particular, as shown in FIG. 4, when the tip of the cleaning blade 7 comes into contact with the intermediate transfer belt 3 wound around the circumference of the stretching roller 10 or the like, the tip of the cleaning blade 7 and the middle in contact with the tip The angle θ formed with the tangent line of the transfer belt region. FIG. 4 is an enlarged schematic view of the vicinity of the cleaning blade in FIG. 1, and is a vertical sectional view with respect to the axial direction of the roller 10. The effective contact angle can be obtained by calculating the deflection using the cross-sectional shape of the cleaning blade and the physical properties such as the Young's modulus of the material. However, in the case of materials such as rubber, the shape of the contact portion is deformed by pressure. Therefore, the calculated value may deviate greatly from the actual value. Therefore, in the present invention, the effective contact angle is an angle measured by observing the cleaning blade in the contact state from the side.
The contact angle can be controlled, for example, by adjusting the arrangement of the holding member 9 that holds the cleaning blade 7 as shown in FIG.

As the linear pressure, a value measured by the following method is used.
The linear pressure can be measured using a load converter that converts a load into a voltage value. As an example of the load transducer, for example, a strain gauge type load transducer 9E01-L43-10N (manufactured by NEC Saneisha) may be mentioned. Specifically, as shown in FIG. 8, as a measurement jig 83, a load converter 80 and a pressurizing unit 81 are incorporated in a cylindrical member 82 to produce a measurement pseudo-cleaning facing member. At this time, the outer peripheral curved surface of the pressing portion 81 has the same radius of curvature as the outer surface of the transfer belt to be measured. 8 is a vertical cross section of the measuring jig 83 with respect to the axis of the cylindrical member, and FIG. 9 is a schematic sketch when the measuring jig of FIG. 8 is viewed from the lateral direction. The blade is brought into pressure contact with the measuring jig 83 using an attachment member having a predetermined setting, and the load is measured. From the load at the contact portion and the distance in the cylindrical member axial direction of the contact portion between the blade and the pressurizing portion of the measuring jig, the linear pressure is calculated according to the following equation.
Linear pressure = Load at the contact portion / Distance in the axial direction of the cylindrical member For the linear pressure, the measured value is used for the same reason as the contact angle.
The linear pressure can be controlled, for example, by adjusting the deflection of the cleaning blade by the arrangement of the holding member 9 that holds the cleaning blade 7 as shown in FIG.

  When an intermediate transfer belt is used as the intermediate transfer member 3, the cleaning blade 7 is usually disposed in contact with the intermediate transfer member at a portion where the intermediate transfer member is wound around the stretching roller, as shown in FIG. . Further, as shown in FIG. 4, the cleaning blade 7 is usually arranged in the counter direction so as to face the moving direction of the intermediate transfer body 3.

  The cleaning blade 7 may be made of any material as long as it has the above-described impact resilience, and is made of, for example, urethane rubber, silicon rubber, fluorine rubber, chloroprene rubber, butadiene rubber, or the like. From the viewpoint of easily achieving the resilience, the cleaning blade 7 is preferably made of urethane rubber.

  The shape of the cleaning blade 7 is not particularly limited, and a known blade shape conventionally employed in the field of the intermediate transfer member cleaning device can be employed. For example, a board shape may be mentioned, and when used, as shown in FIG. 4, the holding member 9 is used in contact with the intermediate transfer body 3.

  As shown in FIG. 5, the primary transfer roller 4 (4a, 4b, 4c, 4d) is arranged on the opposite side of the intermediate transfer member 3 with respect to the latent image carrier 2 (2a, 2b, 2c, 2d). . The primary transfer roller 4 is usually disposed downstream of the contact portion between the latent image carrier 2 and the intermediate transfer member 3 in the intermediate transfer member moving direction 21, and presses the intermediate transfer member 3, whereby a predetermined transfer pressure F Secure. FIG. 5 is an enlarged view of the vicinity of a contact portion (nip portion) between the intermediate transfer member 3 and the latent image carrier 2 (2a, 2b, 2c, 2d) in FIG.

  As the primary transfer roller, a surface in which EPDM, NBR, or the like in which carbon or the like is dispersed is provided on the surface of a metal core can be used.

  As the secondary transfer roller 5, a roller similar to the primary transfer roller can be used.

The tension roller (10, 11) is not particularly limited, and for example, a metal roller such as aluminum or iron can be used. Further, the roller is provided with a coating layer on the outer peripheral surface of the core metal, and the coating layer is obtained by dispersing conductive powder and carbon in an elastic material such as EPDM, NBR, urethane rubber, silicon rubber, and the resistance value. A roller adjusted to 1 × 10 ⁹ Ω · cm or less can also be used.

  Other members / devices included in the image forming apparatus of the present invention, such as a charging device, an exposure device, a developing device, and a latent image carrier cleaning device, are not particularly limited, and are conventionally known in image forming devices. Things can be used.

  For example, the developing device may adopt a one-component developing method using only toner, or may adopt a two-component developing method using toner and a carrier.

The toner may contain toner particles produced by a wet method such as a polymerization method, or may contain toner particles produced by a pulverization method (dry method).
The average particle size of the toner is not particularly limited, and is preferably 7 μm or less, particularly 4.5 μm to 6.5 μm. The average circularity of the toner is preferably 0.910 to 0.985, particularly preferably 0.960 to 0.980. The smaller the average particle size and the higher the average circularity of the toner, the easier the cleaning failure occurs. In the present invention, even with such a particle size and average circularity, the problem of cleaning failure is effectively prevented. it can.

The average particle diameter of the toner is a volume average particle diameter, and a value measured by an espert analyzer (manufactured by Hosokawa Micron Corporation) is used.
The average circularity of the toner can be obtained from the following equation.
Average circularity = peripheral length of a circle equal to the projected area image of particles / perimeter length of the projected particle image The method for measuring the average circularity is not limited, but for example, toner particles were magnified 500 times with an electron microscope. The average circularity can be calculated by taking a photograph, measuring the circularity of 500 toners using an image analysis apparatus, and calculating the arithmetic average value thereof. Further, as a simple measuring method, it can be measured by “FPIA-1000” (manufactured by Toa Medical Electronics Co., Ltd.).

<Experimental example 1>
(Manufacture of transfer belt A)
By extrusion molding, a seamless substrate having a surface resistivity of 1.30 × 10 ⁹ Ω / □ and a thickness of 0.15 mm obtained by dispersing carbon in a PPS resin was obtained.
A 300 nm-thick SiO ₂ thin film layer (hardness 4 GPa, surface roughness Rz 80 nm) was formed on the outer peripheral surface of the substrate by atmospheric pressure plasma CVD to obtain a transfer belt A.

(Manufacture of cleaning blade A)
Urethane rubber having a rebound resilience at 25 ° C. of 23% (manufactured by Syndtech) was cut into dimensions of 2 mm × 13 mm × 330 mm and used as a transfer belt cleaning blade A.

(Manufacture of cleaning blade B)
Urethane rubber (made by Syndtech Co., Ltd.) having a rebound resilience of 50% at 25 ° C. was cut into a size of 2 mm × 13 mm × 330 mm and used as a cleaning blade B for a transfer belt.

(Evaluation)
Cleaning property The transfer belt A and the cleaning blade A or B are mounted on a color MFP Bizhub C352 (manufactured by Konica Minolta Co., Ltd.) configured as shown in FIG. 1, and the printing rate is 50% under an LL environment (10 ° C., 15%). 10,000 images were printed and the images were evaluated for poor cleaning. The cleaning blade was brought into contact with the intermediate transfer member at a predetermined contact angle and linear pressure. The toner was a polymerized toner having an average particle size of 6.5 μm and an average circularity of 0.980.
○: No streaks due to poor cleaning occurred in the image;
X: Streaks were clearly observed in the image.

  6 and 7, the results are shown as graphs showing the relationship between the linear pressure and the contact angle.

<Experimental example 2>
The cleaning performance was evaluated by the same method as in Experimental Example 1 except that a predetermined number of sheets were printed under the conditions shown in Table 1 and an image having a printing rate of 5% was used. Simultaneously with the evaluation of the cleaning property, the amount of wear of the transfer belt was measured.

<Experimental example 3>
(Manufacture of transfer belt B)
The transfer belt B is manufactured by the same manufacturing method as the transfer belt A except that a 500 nm thick SiO ₂ thin film layer (hardness 4 GPa, surface roughness Rz 30 nm) is formed on the outer peripheral surface of the substrate by atmospheric pressure plasma CVD. Obtained.

(Manufacture of transfer belt C)
The transfer belt C is manufactured by the same manufacturing method as the transfer belt A except that a 400 nm thick SiO ₂ thin film layer (hardness 4 GPa, surface roughness Rz 50 nm) is formed on the outer peripheral surface of the substrate by atmospheric pressure plasma CVD. Obtained.

(Manufacture of transfer belt D)
The transfer belt D is manufactured by the same manufacturing method as the transfer belt A, except that a 300 nm thick SiO ₂ thin film layer (hardness 4 GPa, surface roughness Rz 80 nm) is formed on the outer peripheral surface of the substrate by atmospheric pressure plasma CVD. Obtained.

(Manufacture of transfer belt E)
A transfer belt E is manufactured by the same manufacturing method as the transfer belt A, except that a 200 nm thick SiO ₂ thin film layer (hardness 4 GPa, surface roughness Rz 100 nm) is formed on the outer peripheral surface of the substrate by atmospheric pressure plasma CVD. Obtained.

(Manufacture of transfer belt F)
The transfer belt F is manufactured by the same manufacturing method as the transfer belt A, except that a 100 nm thick SiO ₂ thin film layer (hardness 4 GPa, surface roughness Rz 150 nm) is formed on the outer peripheral surface of the substrate by atmospheric pressure plasma CVD. Obtained.

(Evaluation)
The cleaning performance was evaluated by the same method as in Experimental Example 1 except that a predetermined number of sheets were printed under the conditions shown in Table 2.

1 is a schematic configuration diagram of an example of an image forming apparatus of the present invention. FIG. 3 is a schematic cross-sectional view showing a layer configuration of an intermediate transfer member. Explanatory drawing of the manufacturing apparatus which manufactures an intermediate transfer body. FIG. 3 is an enlarged schematic view in the vicinity of a cleaning blade in an example of an embodiment of the present invention. The enlarged view of the primary transfer part in an example of embodiment of this invention. The graph which shows the evaluation result in Experimental example 1. The graph which shows the evaluation result in Experimental example 1. The schematic sectional drawing of the jig | tool for measuring a linear pressure. Schematic sketch of a jig for measuring linear pressure.

Explanation of symbols

  1: 1a: 1b: 1c: 1d: developing unit, 2: 2a: 2b: 2c: 2d: latent image carrier (photosensitive member), 3: intermediate transfer member, 4: 4a: 4b: 4c: 4d: primary transfer Roller, 5: Secondary transfer roller, 6: Transfer object, 7: Cleaning blade, 10:11: Roller, 21: Direction of travel of intermediate transfer member, 31: Substrate, 32: Hard release layer.

Claims (4)

An intermediate transfer body having a hard release layer on the surface, carrying a toner image primarily transferred from the latent image carrier on the hard release layer, and secondarily transferring the carried toner image to a transfer object; and A cleaning blade disposed in contact with the intermediate transfer member to remove toner remaining on the hard release layer of the intermediate transfer member;
An image forming apparatus comprising:
The surface roughness Rz of the hard release layer is 50 to 100 nm,
An image forming apparatus, wherein the cleaning blade has a rebound resilience of 20 to 60% and is in contact with the intermediate transfer member at a contact angle of 8 to 15 ° and a linear pressure of 25 to 40 N / m.   The image forming apparatus according to claim 1, wherein the hardness of the hard release layer by a nanoindentation method is 3 GPa or more.   The image forming apparatus according to claim 1, wherein the hard release layer is an inorganic oxide layer or a hard carbon-containing layer.   The image forming apparatus according to claim 1, wherein the intermediate transfer member has a seamless belt shape.

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