Image forming apparatus and process cartridge

Abstract

The present invention relates to a cleaning blade for an image carrier, a process cartridge, and an image forming apparatus, which can suppress an increase in torque even after the start of use of the image forming apparatus, and can obtain good cleaning properties even if high-concentration images are continuously printed. The cleaning blade for the image carrier, which is in contact with the surface of the image carrier and removes residues on the surface of the image carrier, is characterized in that: the cleaning blade comprises a cleaning blade base body having an elastic cleaning blade base body, and a cleaning blade support member for supporting the cleaning blade base body; the elastic cleaning blade substrate is provided with an edge layer and a coating layer arranged on a tip ridge portion abutting against the image bearing body. The maximum depth of penetration hmax of an indenter of a microhardness tester according to a nanoindentation hardness test at a position of the coating layer on the lower surface of the cleaning blade substrate at a distance of 100 [mu] m inward from a tip ridge portion is 4.0 [mu] m or more and 10.0 [mu] m or less.

Description

Technical Field

[0001] The present invention relates to a cleaning blade for a carrier, a processing cartridge, and an image forming apparatus. Background Art

[0002] Conventionally, in an electrophotographic image forming apparatus, residual toner adhering to the surface of an image carrier (also referred to as a member to be cleaned) after transferring a toner image to a recording medium or an intermediate transfer body through an image forming process is removed by a cleaning means.

[0003] As the above-described cleaning means, a cleaning blade is used from the viewpoints of simple configuration and excellent cleaning performance. The above-described cleaning blade generally includes an elastic cleaning blade base body and a support member, and the elastic cleaning blade base body is made of polyurethane rubber or the like. Then, the bottom end of the elastic cleaning blade base body is supported by the support member, and the contact portion (tip ridge line portion) of the elastic cleaning blade base body is pressed against the surface of the image carrier to block the toner remaining on the surface of the image carrier and scrape it off to remove it.

[0004] In the cleaning means using the above-described cleaning blade, since the cleaning blade contacts the image carrier, the following problems sometimes occur: Friction is generated between the cleaning blade and the image carrier, the torque as the force required to rotate the image carrier increases, and the image carrier stops. In addition, due to the sliding friction between the cleaning blade and the image carrier, the contact portion is worn and warped, and the toner slides out from the warped portion, and as a result, a problem of poor cleaning sometimes occurs.

[0005] For example, in recent years, in the case of the above-described cleaning blade, in order to reduce the frictional force with the image carrier, a cleaning blade coated with a lubricant containing a fluorine compound has been used, and a cleaning blade in which the fluorine compound contained in the lubricant is vinylidene fluoride has been proposed (Patent Documents 1 to 5). In addition, in order to impart appropriate softness and hardness to the elastic cleaning blade base body in the cleaning blade and prevent warping or scratch wear of the tip ridge line portion in the cleaning blade, a cleaning blade has been proposed in which the Martens hardness of the surface at a position only 20 [μm] away from the tip ridge line portion to the inside of the elastic cleaning blade base body is 1.0 [N / mm 2 to 15.0 [N / mm 2 (Patent Document 6). Further, in order to improve the sliding mobility of the cleaning blade, a cleaning blade coated with a dispersion liquid obtained by dispersing PMMA (polymethacrylic acid) particles in a fluorine-based solvent has been proposed (Patent Document 7).

[0006] An object of the present invention is to provide a cleaning blade for an image carrier, which can suppress an increase in torque even immediately after the start of use of an image forming apparatus, and can obtain good cleanability even when continuously printing high-concentration images such as all-solid images.

[0007] [Patent Document 1] Japanese Patent Laid-Open No. 2000-147972

[0008] [Patent Document 2] Japanese Patent Laid-Open No. 2004-101551

[0009] [Patent Document 3] Japanese Patent No. 3278733

[0010] [Patent Document 4] Japanese Patent Laid-Open No. 10-214009

[0011] [Patent Document 5] Japanese Patent Laid-Open No. 6-348193

[0012] [Patent Document 6] Japanese Patent Laid-Open No. 2017-16083

[0013] [Patent Document 7] Japanese Patent No. 2853598 Summary of the Invention

[0014] A cleaning blade for an image carrier according to the present invention as a means for solving the above problems is a cleaning blade for an image carrier that abuts against the surface of the image carrier and removes residues on the surface of the image carrier, characterized in that: the cleaning blade includes a cleaning blade base body having an elastic cleaning blade base body, and a cleaning blade support member that supports the cleaning blade base body, the elastic cleaning blade base body has an edge layer and a coating layer provided on a leading edge line portion that abuts against the image carrier, and the maximum indentation depth hmax of the indenter of a microhardness tester based on a nanoindentation hardness test at a position where the coating layer on the lower surface of the cleaning blade base body is 100 [μm] away from the leading edge line portion toward the inside is 4.0 [μm] or more and 10.0 [μm] or less.

[0015] According to the present invention, a cleaning blade for an image carrier can be provided, which can suppress an increase in torque even immediately after the start of use of an image forming apparatus, and can obtain good cleanability even when continuously printing high-concentration images such as all-solid images. Brief Description of the Drawings

[0016] Figure 1 Shown is a schematic cross-sectional view of an example of a state where the cleaning blade abuts against the surface of the image carrier.

[0017] Figure 2The figure shows a perspective view of an example of the cleaning blade for an image carrier of the present invention.

[0018] Figure 3 The figure shows a schematic cross-sectional view of another example of the cleaning blade for an image carrier of the present invention.

[0019] Figure 4 The figure shows a schematic cross-sectional view of an example of an image forming apparatus of the present invention.

[0020] Figure 5 The figure shows Figure 4 a schematic cross-sectional view of an example of an image forming unit in the image forming apparatus.

[0021] Figure 6 The figure shows a schematic view of the case of the formation method of the coating layer performed in the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, Figure 3 taking the cleaning blade shown as an example, the embodiment of the present invention will be described. The cleaning blade 62 is composed of a cleaning blade support member 621 and a cleaning blade base body 622. The cleaning blade base body 622 includes an elastic edge layer 622a, a base layer 622b, a contact portion 62c, and a coating layer 623 on at least a part of the contact edge in the contact portion 62c.

[0023] In addition, hereinafter, an embodiment in which the above cleaning blade 62 is applied to the cleaning of an image carrier as a member to be cleaned will be described.

[0024] In addition, hereinafter, the "cleaning blade for an image carrier" of the present invention will sometimes be referred to as a "cleaning blade".

[0025] Hereinafter, the "blade base body in the cleaning blade" will sometimes be referred to as the "blade base body".

[0026] [Cleaning Blade]

[0027] One embodiment of the cleaning blade of the present invention is a cleaning blade for cleaning an image carrier. The cleaning blade includes a cleaning blade base body having an elastic cleaning blade base body, and a cleaning blade support member for supporting the cleaning blade base body. The elastic cleaning blade base body has a coating layer provided on the leading edge portion in contact with the member to be cleaned. The maximum penetration depth hmax of the indenter of the microhardness tester based on the nanoindentation hardness test at a position 100 [μm] away from the leading edge portion inward in the coating layer on the lower surface of the cleaning blade base body is 4.0 [μm] or more and 10.0 [μm] or less, and may further include other components as needed.

[0028] The cleaning blade of the present invention is a cleaning blade that removes residues attached to the image carrier by abutting against the surface of the image carrier.

[0029] As the above residues, as long as they are substances attached to the surface of the above image carrier and are the objects to be removed by the above cleaning blade, there is no particular limitation. For example, toner, lubricant, inorganic particles, organic particles, garbage, dust, or a mixture thereof can be cited.

[0030] In the cleaning means using the existing cleaning blade, due to the friction generated by the contact between the above cleaning blade and the above image carrier, the torque as the force required to rotate the above image carrier increases, and there is a problem that the rotation of the above image carrier stops. In addition, due to the above friction, the contact portion of the above cleaning blade with the above image carrier wears, resulting in warping of the above cleaning blade or leakage of toner, and there is a problem of poor cleaning.

[0031] In order to improve the sliding mobility of the above cleaning blade and prevent warping of the cleaning blade or an increase in torque, a process (touchup) of coating a metal soap such as zinc stearate or PMMA (polymethacrylic acid) particles at the front end of the above cleaning blade as a lubricant is widely used. Usually, as the image forming apparatus operates, toner gradually accumulates between the above cleaning blade and the above image carrier, and the above toner functions as a lubricant. Therefore, the above lubricant only needs to exhibit lubricating properties within a very short period from the start of operation of the image forming apparatus until the operation behavior of the cleaning blade becomes stable. However, the adhesion of the particles contained in the conventional lubricant to the base material is weak, and there is a problem of detachment from the above cleaning blade before the operation behavior of the cleaning blade becomes stable.

[0032] In order to suppress the detachment of the above particles from the cleaning blade, a known technique is to coat a lubricant composed of the above particles and a bonding component for fixing the above particles at the contact portion of the above cleaning blade with the above image carrier. Since the above particles are difficult to detach from the above cleaning blade due to the above bonding component, it has the effect of preventing an increase in torque. However, since the above lubricant easily remains on the above cleaning blade, it is difficult for the front end of the above cleaning blade to be exposed, the pressure applied to the contact portion with the above image carrier decreases, and the cleaning performance deteriorates. This becomes more significant in the case where a large amount of toner rushes into the contact portion between the above cleaning blade and the above image carrier, such as in continuous printing of a full solid image.

[0033] The inventors of the present invention have found through in-depth research that in the lubricant composed of the above-mentioned fine particles and the above-mentioned binder component, by making the coating layer composed of the above-mentioned lubricant brittle and easily broken, while continuously preventing the torque from rising, even if the coating layer at the front end of the above-mentioned cleaning blade is easily shaved off and the front end portion of the blade is exposed in advance, and the pressure applied to the contact portion with the above-mentioned image carrier rises, such as in the case of continuous printing of a full-solid image where a large amount of toner rushes into the contact portion between the above-mentioned cleaning blade and the above-mentioned image carrier, the cleaning performance can be maintained, and both preventing torque rise and cleaning performance can be achieved.

[0034] Therefore, in the present invention, there is provided a cleaning blade that uses an image carrier as a cleaning object, has an edge layer and a coating layer, and the coating layer provided at the front end portion in the above-mentioned edge layer that comes into contact with the above-mentioned image carrier is composed of fine particles and a binder component. At the lower surface of the coating layer of the blade, the maximum penetration depth hmax of the indenter of a microhardness tester at a position 100 μm away from the leading edge line portion toward the inside is 4.0 μm or more and 10.0 μm or less. Thus, even immediately after the image forming apparatus starts to be used, the rise in torque can be suppressed, and even in the case where a large amount of toner rushes into the contact portion with the above-mentioned image carrier, such as in the continuous printing of a full-solid image, a cleaning blade with good cleaning performance can be obtained.

[0035] <Coating layer>

[0036] The above-mentioned coating layer contains fine particles and a binder component incompatible with the above-mentioned fine particles, and if necessary, also contains other components. The above-mentioned coating layer refers to a layer provided at one end used as the front end of the above-mentioned cleaning blade on the circumferential side surface of the following blade base. The above-mentioned coating layer can be formed on at least a part of the contact edge where the above-mentioned cleaning blade and the above-mentioned image carrier come into contact with each other on the above-mentioned blade base, or can be formed on the entire above-mentioned contact edge, or can be formed on the entire surface of the above-mentioned blade base. Among them, it is preferable that the above-mentioned coating layer is formed on the entire above-mentioned contact edge. In addition, the surface area of the blade base where the above-mentioned coating layer is not provided is sometimes referred to as a non-coated area.

[0037] Preferably, the average thickness of the above-mentioned coating layer in the above-mentioned cleaning blade is 0.5 μm or more and 10 μm or less. When the average thickness of the above-mentioned coating layer is 0.5 [μm] or more, a sufficient sliding effect can be obtained. When the average thickness of the above-mentioned coating layer is 10 [μm] or less, the effect of maintaining cleaning performance due to the above-mentioned coating layer being easily brittle and broken can be obtained. As the average thickness in the above-mentioned coating layer, the average value of the thickness [μm] measured at three or more places in the above-mentioned coating layer can be adopted. As the measurement part of the average thickness in the above-mentioned coating layer, the central part in the above-mentioned coating layer at a position 100 [μm] away from the end portion toward the inside can be cited, etc.

[0038] As a method for measuring the average thickness in the above-mentioned coating layer, a part of the above-mentioned coating layer can be shaved off using a trowel or a cotton swab, etc., and a three-dimensional measuring machine such as a contact surface roughness meter (Surftest SJ-500: manufactured by Mitutoyo) or a laser microscope (LEXTOLS4100: manufactured by Olympus Corporation) can be used for shape measurement, thereby performing the measurement.

[0039] Here, an embodiment and other embodiments of the cleaning blade of the present invention will be described with reference to the accompanying drawings. Among them, the use of the cleaning blade of the present invention is not limited to these embodiments. In addition, in each figure, the same reference numerals are given to the same structural parts, and the repeated description thereof may be omitted. In addition, the number, position, shape, etc. of the following constituent parts are not limited to this embodiment, and appropriate numbers, positions, shapes, etc. can be selected when implementing the present invention.

[0040] Figure 1 Shown is a schematic cross-sectional view of an embodiment of the cleaning blade of the present invention, showing a state where the above-mentioned cleaning blade is in contact with the surface of the above-mentioned image carrier. Figure 2 is Figure 1 Shown are a perspective view of the cleaning blade and an enlarged view of the vicinity of the contact portion. The cleaning blade 62 includes: a flat cleaning blade support member 621 made of a rigid material such as metal or hard plastic, and a flat cleaning blade base 622 having one end connected to the above-mentioned cleaning blade support member 621 and a free end with a predetermined length at the other end. The above-mentioned cleaning blade base 622 is fixed to one end of the above-mentioned cleaning blade support member 621 by an adhesive or the like, and the other end of the cleaning blade support member 621 is supported on the housing of the cleaning device in a cantilever manner. The above-mentioned cleaning blade base 622 includes a cleaning blade front surface 62a, a cleaning blade lower surface 62b, a cleaning blade contact portion 62c at one end on the free end side of the cleaning blade base 622, and a cleaning blade side surface 62d, and has a coating layer 623 on at least a part of the contact edge in the above-mentioned cleaning blade contact portion 62c. The above-mentioned cleaning blade 62 is configured such that the cleaning blade contact portion 62c contacts the surface of the above-mentioned image carrier 3 along the long side direction.

[0041] Figure 3 Shown is a schematic cross-sectional view of another embodiment of the cleaning blade of the present invention. The cleaning blade 62 is composed of a cleaning blade support member 621 and a cleaning blade base 622. The above-mentioned cleaning blade base 622 includes an elastic edge layer 622a, a base layer 622b, a contact portion 62c, and a coating layer 623 on at least a part of the contact edge in the above-mentioned contact portion 62c. In addition, the cleaning blade front surface 62a, the cleaning blade lower surface 62b, and the cleaning blade side surface 62d are omitted.

[0042] The coating layer in the present invention is composed of particles and a resin as a binder component. As one aspect of the present invention, the above-mentioned particles are preferably in the domain of the sea-island structure possessed by the above-mentioned coating layer. The above-mentioned particles are preferably selected in terms of the type and addition amount of the particles according to the type of the resin of the binder component to form a domain.

[0043] The shape of the above-mentioned particles is not particularly limited and can be appropriately selected according to the purpose. It can be regular or irregular. Among them, a regular shape is preferred. When the shape of the above-mentioned domain is regular, a spherical shape is preferred. By such a shape, it is possible to prevent adverse conditions such as particles detached from the above-mentioned coating layer damaging the intermediate transfer body, the blade substrate in the cleaning blade, etc., and thus it is preferred.

[0044] The volume average particle diameter (50% volume diameter, median diameter) of the above-mentioned particles is not particularly limited and can be appropriately selected according to the purpose. It is preferably 0.1 [μm] or more and 1 [μm] or less, more preferably 0.1 [μm] or more and 0.5 [μm] or less, and further preferably 0.1 [μm] or more and 0.3 [μm] or less. When the volume average particle diameter of the above-mentioned particles is 1 μm or less, it is possible to prevent problems such as easy sedimentation in the solvent and difficult stable dispersion. In addition, when the volume average particle diameter of the above-mentioned particles is 0.5 [μm] or less, it can be more stably dispersed in the non-aqueous solvent.

[0045] The method for measuring the above-mentioned volume average particle diameter (50% volume diameter, median diameter) is not particularly limited and can be appropriately selected according to the purpose. For example, it can be measured by laser diffraction / scattering method, dynamic light scattering method, image imaging method, etc. Specific examples of the method for measuring the above-mentioned volume average particle diameter can include a method of measuring the particles collected from the coating layer of the above-mentioned cleaning blade by putting them into Microtrac (manufactured by Nikkiso Co., Ltd.) by laser diffraction / scattering method, and a method of directly observing the fine particles on the cleaning blade using a scanning electron microscope (SEM) for measurement, etc. In addition, the volume average particle diameter of the particles hardly changes when added to the dispersion liquid coated on the cleaning blade and when present in the coating layer.

[0046] The content of the above-mentioned particles in the above-mentioned coating layer is not particularly limited and can be selected according to the purpose. However, from the viewpoints of obtaining a sliding effect and making the above-mentioned coating layer brittle due to relatively more than the binder component and the above-mentioned particles being easily detached, it is preferably 80% by mass or more and 99% by mass or less, more preferably 90% by mass or more and 98% by mass or less, relative to the total mass of the above-mentioned coating layer.

[0047] The material of the above particles is not particularly limited and can be selected according to the purpose. For example, polytetrafluoroethylene (PTFE), fluorinated ethylene-propylene copolymer (FEP), perfluoroalkoxy polymer (PFA), chlorotrifluoroethylene copolymer (CTFE), tetrafluoroethylene-chlorotrifluoroethylene copolymer (TFE / CTFE), ethylene-chlorotrifluoroethylene copolymer (ECTFE), polychlorotrifluoroethylene (PCTFE), etc. can be cited. Among them, from the viewpoint of further improving the sliding mobility of the cleaning blade, polytetrafluoroethylene (PTFE) is preferred.

[0048] The above polytetrafluoroethylene (PTFE) can be appropriately synthesized or commercially available products can be used. As commercially available products of the above polytetrafluoroethylene (PTFE), for example, DyneonTFMicroPowderTF-9201Z, DyneonTFMicroPowderTF-9207Z (both manufactured by 3M), NanoFLON119N, FLUOROE (both manufactured by Shamrock), TLP10F-1 (manufactured by Mitsui-DuPont Fluorochemical Co., Ltd.), KTL-500F (manufactured by Kitamura Co., Ltd.), AlgoflonL203F (manufactured by SOLVAY), etc. can be cited.

[0049] In the present invention, by containing a bonding component in the above coating layer, the adhesion of the above particles to the cleaning blade substrate can be improved, and the detachment of the above coating layer can be prevented. Therefore, the warping of the cleaning blade and the increase in torque can be prevented. As one aspect of the present invention, the above bonding component is preferably the matrix in the sea-island structure of the above coating layer. The above bonding component is preferably selected in terms of the type and addition amount of the resin with the above particles to form a matrix.

[0050] As the above bonding component, as long as it can uniformly and stably disperse the above particles, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, vinylidene fluoride (VdF), hexafluoropropylene (HFP), tetrafluoroethylene (TFE), etc. can be cited. Among them, from the viewpoints of lubricity and close contact with the blade substrate, a copolymer combining them is preferred, and a terpolymer of VdF-HFP-TFE is more preferred.

[0051] From the viewpoints of imparting flexibility to the blade and solubility in solvents, the composition of VdF / HFP / TFE in the above terpolymer is preferably 30 mol% to 80 mol% / 10 mol% to 35 mol% / 5 mol% to 35 mol% in terms of their respective monomer units.

[0052] The above-mentioned particles and the above-mentioned binder components are not limited to the examples shown above, and can be appropriately selected according to the purpose. For example, fine particles of inorganic compounds, acrylic resins, styrene resins, vinyl resins, etc. can be cited. As the fine particles of the above-mentioned inorganic compounds, silica, alumina, zirconia, etc. can be cited.

[0053] These can be used alone as one kind, or two or more kinds can be used in combination.

[0054] The coating layer is preferably a coating film composed of PTFE particles and a fluororesin, or a coating film composed of acrylic particles and a polyvinyl alcohol resin or a polyvinyl acetal resin.

[0055] As the particles other than the above-mentioned fluororesin, acrylic resins that can be expected to have the effect of sliding mobility because of having a certain degree of hardness are preferred. On the other hand, there is no particular limitation on the shape, and it can be appropriately selected according to the purpose, and a spherical shape is preferred. With such a shape, it is possible to prevent the particles other than the above-mentioned fluororesin that have detached from the above-mentioned coating layer from damaging the carrier or the blade base in the cleaning blade, so it is preferred.

[0056] Regarding the volume average particle diameter (50% volume diameter, median particle diameter) of the particles other than the above-mentioned fluororesin, there is no particular limitation, and it can be appropriately selected according to the purpose. It is preferably 0.1 [μm] or more and 1 [μm] or less, more preferably 0.5 [μm] or less, and further preferably 0.3 [μm] or less. When the volume average particle diameter of the above-mentioned particles is 1 μm or less, problems such as easy sedimentation in the solvent and difficulty in stable dispersion can be prevented. In addition, when the volume average particle diameter of the above-mentioned particles is 0.5 [μm] or less, it can be more stably dispersed in the non-aqueous solvent.

[0057] Regarding the manufacturing method of the above-mentioned coating layer, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, it can be obtained by adding particles to a mixture of a solvent and a binder component, and coating the obtained particle dispersion on the blade base in the above-mentioned cleaning blade.

[0058] Regarding the above-mentioned solvent, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, in the case of fluorine-based particles and a binder component, fluorine-containing organic solvents can be cited. As the above-mentioned fluorine-containing organic solvents, for example, hydrofluoroethers (HFE), perfluorocarbons (PFC), perfluoroethers (PFE), etc. can be cited. These materials can be used alone as one kind, or two or more kinds can be used in combination.

[0059] In the present invention, from the viewpoint of obtaining a uniform dispersion, the average particle size (average particle size in the cumulant analysis of the scattering intensity distribution) of the particles in the above-mentioned binder component by dynamic light scattering method is preferably 1 μm or less, more preferably 0.5 μm or less, and further preferably 0.3 μm or less. Generally, even when using fine particles with a volume average particle size of 1 [μm] or less, secondary particles are formed by particle aggregation, and the volume average particle size becomes fine particles of 1 [μm] or more. By dispersing the fine particles that aggregate to form secondary particles into particles with a particle size of 1 [μm] or less, a stable dispersion can be obtained even when the above-mentioned fluororesin dispersion is stored at a low viscosity for a long time. As the dispersion method, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, methods using dispersers such as ultrasonic dispersers, three-roll mills, ball mills, bead mills, and jet mills can be cited.

[0060] As the method for forming the above-mentioned coating layer, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, dipping in which the entire blade substrate of the above-mentioned cleaning blade or a part of the blade substrate is immersed in the particle dispersion for treatment can be cited. In addition to the above-mentioned dipping, coating methods such as spray coating and dispenser can also be used.

[0061] <Blade substrate>

[0062] In the present invention, the blade substrate in the above-mentioned cleaning blade is sometimes referred to as "blade substrate" or "substrate". As the shape of the above-mentioned blade substrate, any structure that can remove the above-mentioned residue on the image carrier can be appropriately selected according to the purpose. However, it is preferable that the contact edge in the contact portion of the above-mentioned blade substrate with the above-mentioned image carrier is linear. As the shape of the above-mentioned blade substrate, for example, a plate shape can be cited.

[0063] As the structure of the above-mentioned blade substrate, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, a single-layer structure, a laminated structure, and a laminated structure formed by combining multiple components can be cited. Among them, from the viewpoint of being easily processed into the above-mentioned cleaning blade, a single-layer structure and a laminated structure formed by laminating multiple components are preferred. When the above-mentioned blade substrate has a laminated structure, the layer in contact with the above-mentioned image carrier is sometimes referred to as the edge layer, and the layer that is not the above-mentioned edge layer is referred to as the base layer. In addition, when the above-mentioned blade substrate is single-layer, the above-mentioned blade substrate only has an edge layer. More preferably, the Martens hardness of the multiple components in the above-mentioned laminated structure is different from each other.

[0064] As the material of the above-mentioned blade substrate, there is no particular limitation, and it can be appropriately selected according to the purpose. However, from the viewpoints of preventing wear of the above-mentioned blade substrate and sufficiently removing the above-mentioned residue on the image carrier, it is preferably moderately elastic and hard. As the material of the above-mentioned blade, for example, an elastic material can be cited. As the above-mentioned elastic material, as long as it is highly elastic, there is no particular limitation, and it can be appropriately selected according to the purpose. Examples thereof include polyurethane rubber, silicone rubber, fluororubber, nitrile rubber (NBR), ethylene propylene diene monomer (EPDM), etc. Among them, from the viewpoints of durability and non-pollution, polyurethane rubber is preferred. As the size of the above-mentioned blade substrate, there is no particular limitation, and it can be appropriately selected according to the size of the above-mentioned image carrier.

[0065] The Shore hardness of the above-mentioned polyurethane rubber in the cleaning blade of the present invention is not particularly limited and can be appropriately selected according to the purpose. It is preferably 0.5 [N / mm 2 or more and 2 [N / mm 2 or less. By making the Shore hardness of the above-mentioned polyurethane rubber in the cleaning blade within the desired range, it is possible to eliminate defects such as poor cleaning caused by difficulty in obtaining the blade line pressure and easy expansion of the contact area with the image carrier, and defects caused by the above-mentioned blade substrate becoming too hard.

[0066] As the manufacturing method of the above-mentioned blade substrate, there is no particular limitation and it can be appropriately selected according to the purpose. For example, a polyurethane prepolymer can be prepared by using a polyol compound and a polyisocyanate compound, and after adding a curing agent and, if necessary, a curing catalyst to the above-mentioned polyurethane prepolymer, it is centrifugally molded in a specified mold, left at room temperature to complete (cure), and then the obtained product is cut into a flat plate shape with a specified size to obtain it.

[0067] As the above-mentioned polyol compound, there is no particular limitation and it can be appropriately selected according to the purpose. For example, high molecular weight polyols, low molecular weight polyols, etc. can be cited.

[0068] As the above-mentioned high molecular weight polyol, for example, condensates of alkylene glycols and aliphatic dibasic acids such as polyester polyols, ethylene glycol adipate polyols, butanediol adipate polyols, hexanediol adipate polyols, ethylene glycol propylene glycol adipate polyols, ethylene glycol butanediol adipate polyols, ethylene glycol neopentyl glycol adipate polyols, etc., polyester-based polyols such as polyester polyols of alkylene glycols and adipic acid; polycaprolactone-based polyols such as polycaprolactone polyols obtained by ring-opening polymerization of caprolactone; polyether-based polyols such as poly(tetramethylene oxide) glycol, poly(propylene oxide) glycol, etc. These can be used alone as one kind or in combination of two or more kinds.

[0069] As the above-mentioned low-molecular-weight polyol, for example, there can be cited diols such as 1,4-butanediol, ethylene glycol, neopentyl glycol, hydroquinone-bis(2-hydroxyethyl) ether, 3,3'-dichloro-4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, etc., and polyols with three or more hydroxyl groups such as 1,1,1-trimethylolpropane, glycerin, 1,2,6-hexanetriol, 1,2,4-butanetriol, trimethylolethane, 1,1,1-tris(hydroxyethoxymethyl)propane, diglycerin, pentaerythritol, etc. These can be used alone as one kind or in combination of two or more kinds.

[0070] As the above-mentioned polyisocyanate compound, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, there can be cited methylene diphenyl diisocyanate (MDI), dimethyl biphenyl diisocyanate (TDI), xylylene diisocyanate (XDI), 1,5-naphthalene diisocyanate (NDI), tetramethyl xylylene diisocyanate (TMXDI), isophorone diisocyanate (IPDI), hydrogenated xylylene diisocyanate (H6XDI), dicyclohexylmethane diisocyanate (H12MDI), hexamethylene diisocyanate (HDI), dimer acid diisocyanate (DDI), norbornene diisocyanate (NBDI), trimethyl hexamethylene diisocyanate (TMDI), etc. These can be used alone as one kind or in combination of two or more kinds.

[0071] As the above-mentioned curing agent, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, there can be cited amines, alcohols, etc. These can be used alone as one kind or in combination of two or more kinds. The above-mentioned curing agent is used, for example, to adjust the hardness of the above-mentioned blade substrate.

[0072] The above-mentioned curing catalyst is not particularly limited and can be appropriately selected according to the intended purpose. For example, 2-methylimidazole and 1,2-dimethylimidazole, etc. can be cited. The content of the above-mentioned curing catalyst is not particularly limited and can be appropriately selected according to the purpose, but it is preferably 0.01% by mass or more and 0.5% by mass or less, more preferably 0.05% by mass or more and 0.3% by mass or less, based on the total mass of the prepolymer and the curing agent.

[0073] The resilience modulus of elasticity of the blade base material according to JIS K6255 is not particularly limited and can be appropriately selected according to the purpose. It is preferably 10% to 80% at 23°C. By making the resilience modulus of elasticity within the desired range, it is possible to eliminate the cleaning defects caused by the loss of softness of the entire blade base material and the inability to follow the vibration or roughness of the carrier, or the abnormal sound (scraping noise) caused by excessive resilience. The resilience coefficient of the blade base material can be measured, for example, according to JIS K6255 at 23°C using an elastic tester No. 221 manufactured by Toyo Seiki Seisakusho Co., Ltd.

[0074] <Maximum indentation depth hmax of the indenter>

[0075] In the cleaning blade of the present invention, the maximum indentation depth of the indenter at a position 100 [μm] inward from the tip edge line portion of the edge layer is 4.0 [μm] or more and 10.0 [μm] or less. Thus, the effect that the coating layer becomes sufficiently brittle and easily broken can be obtained. From the viewpoint of achieving both the sliding effect and the cleaning performance brought about by the easy breakage of the film, the hmax at a position 100 [μm] inward from the tip edge line portion of the edge layer in the cleaning blade of the present invention is preferably 5.5 [μm] or more and 7.5 [μm] or less. When the hmax at a position 100 [μm] inward from the tip edge line portion of the edge layer in the cleaning blade is 4.0 [μm] or more, since the coating layer is easily broken, the problem of maintaining the cleaning performance even when continuously printing high-concentration images can be eliminated, so it is preferable. If the hmax at a position 100 [μm] inward from the tip edge line portion of the edge layer in the cleaning blade is less than 4.0 [μm], since the coating layer is difficult to break, the cleaning performance cannot be maintained when continuously printing high-concentration images. On the contrary, if hmax exceeds 10.0 [μm], the sliding mobility cannot be maintained because the coating layer is too easily broken, or the coating layer may spontaneously fall off from the cleaning blade when not in use. In addition, the measurement of the Martens hardness in the present invention is carried out after processing into a cleaning blade.

[0076] -Measurement of the maximum indentation depth hmax of the indenter-

[0077] The maximum penetration depth hmax of the indenter described above is measured, for example, based on ISO14577, using a nanoindenter (ENT-3100, manufactured by Elionix Corporation). The Berkovich indenter is pressed into a sample for 10 seconds with a load of 1,000 [μN], held for 5 seconds, and then pulled out for 10 seconds at the same load rate. hmax is calculated from the load-displacement curve. In the present invention, hmax is the depth of the indenter after holding for 5 seconds. As the measurement position of the edge layer described above, as Figure 3 shown, it is a position at a distance of 100 [μm] from the tip ridge portion (62c) of the edge layer toward the inside. In addition, the load rate is such that the load is increased at a constant rate from 0 μN in 10 seconds and reaches 1,000 μN after 10 seconds.

[0078] <Measurement of Martens hardness>

[0079] As the measurement position of the Martens hardness in the base layer of the cleaning blade described above, there is no particular limitation. From the viewpoint of ease of measurement, it is set to a position at a distance of 100 [μm] from the end of the base layer toward the inside. In addition, the Martens hardness is the median value of the values obtained by measuring 4 to 6 points at each measurement position. In addition, the measurement conditions are the same as those in the measurement of the "maximum penetration depth hmax of the indenter" described above.

[0080] <Processing cartridge>

[0081] A processing cartridge according to an embodiment of the present invention includes an image carrier; at least one of charging means for charging the surface of the image carrier, exposure means for exposing the charged surface of the image carrier to form an electrostatic latent image, developing means for developing the electrostatic latent image into a toner image, and transfer means for transferring the toner image onto a recording medium; and cleaning means for contacting the surface of the image carrier and removing residues on the surface of the image carrier. The cleaning means includes the cleaning blade. The processing cartridge is detachable from the main body of the image forming apparatus and may further include other means as needed.

[0082] [Image forming apparatus and image forming method]

[0083] The image forming apparatus of the present invention at least has an image carrier, a charging means for charging the surface of the above-mentioned image carrier, an exposure means for exposing the charged above-mentioned image carrier to form an electrostatic latent image, a developing means for developing the above-mentioned electrostatic latent image with toner to form a visible image, a transfer means for transferring the above-mentioned visible image to a recording medium via an intermediate transfer body, a fixing means for fixing the transferred image on the above-mentioned recording medium, and a cleaning means for removing the toner remaining on the above-mentioned intermediate transfer body. Further, according to need, other means appropriately selected may also be provided. The above-mentioned charging means and the above-mentioned exposure means are sometimes collectively referred to as an electrostatic latent image forming means. In addition, the above-mentioned cleaning means respectively has a cleaning blade of the present invention.

[0084] The image forming method used in the present invention at least includes a charging step, an exposure step, a developing step, a transfer step, a fixing step, and a cleaning step. Further, according to need, other steps appropriately selected may also be included. In addition, the above-mentioned charging step and the above-mentioned exposure step are sometimes collectively referred to as an electrostatic latent image forming step.

[0085] The image forming method used in the present invention can be appropriately implemented by the image forming apparatus of the present invention. The above-mentioned charging step can be performed by the above-mentioned charging means, the above-mentioned exposure step can be performed by the above-mentioned exposure means, the above-mentioned developing step can be performed by the above-mentioned developing means, the above-mentioned transfer step can be performed by the above-mentioned transfer means, the above-mentioned fixing step can be performed by the above-mentioned fixing means, the above-mentioned cleaning step can be performed by the above-mentioned cleaning means, and the above-mentioned cleaning means has a cleaning blade of the present invention. The above-mentioned other steps can be performed by the above-mentioned other means.

[0086] <Image carrier>

[0087] As the above-mentioned image carrier, there are no particular limitations on its structure, size, etc., and it can be appropriately selected from known ones. There are no particular limitations on the shape of the above-mentioned image carrier, and it can be appropriately selected according to the purpose. For example, a drum shape, a belt shape, etc. can be cited. As the material of the above-mentioned image carrier, there are no particular limitations, and it can be appropriately selected according to the purpose. Examples include inorganic photoreceptors such as amorphous silicon and selenium, and organic photoreceptors (OPC) such as polysilane and phthalocyanine polymethine.

[0088] As the above-mentioned organic photoreceptor, a laminated photoreceptor having a laminated structure on a support such as an aluminum drum can be cited. The laminated structure includes a layer (charge generation layer) in which a charge generation material such as metal-free phthalocyanine or titanium-oxy phthalocyanine is dispersed in a binder resin, and a layer (charge transport layer) in which a charge transport material is dispersed in a binder resin, and a single-layer photoreceptor having a photosensitive layer with a single-layer structure in which both a charge generation material and a charge transport material are dispersed in a binder resin on a support.

[0089] In a single-layer photoreceptor, a hole transport agent and an electron transport agent may be added to the photosensitive layer as a charge transport material.

[0090] Furthermore, an undercoat layer may be provided between the support and the stacked charge generating layer or the single-layer photosensitive layer.

[0091] <Charging process and charging methods>

[0092] The charging step is a step for charging the surface of the image carrier, and is performed by the charging means. The charging means is not particularly limited as long as it can charge the surface of the image carrier, and may be appropriately selected depending on the intended purpose. Examples include known contact chargers such as conductive or semiconductive rollers, brushes, films, and rubber blades, and non-contact chargers utilizing corona discharge using corotrons, corona wires, and the like.

[0093] The charging means may be in any form, such as a roller, a magnetic brush, or a fur brush, and may be selected based on the specifications and configuration of the electrophotographic image forming apparatus. When a magnetic brush is used, the charging means may be composed of various ferrite particles, such as Zn-Cu ferrite, and may be comprised of a non-magnetic conductive sleeve supporting the charging means and a magnetic roller contained within the conductive sleeve.

[0094] In the case of using a brush, for example, conductively treated hair of carbon, copper sulfide, metal or metal oxide can be used as the brush material, and the charger can be manufactured by rolling or sticking it onto a metal or other conductively treated core shaft.

[0095] The charger is not limited to the contact type described above, but is preferred from the perspective of achieving an image forming apparatus that reduces ozone generated by the charger. The charger is preferably positioned in contact or non-contact with the image carrier, and charges the surface of the image carrier by applying DC and AC voltages in a superimposed manner. Furthermore, the charger is preferably a charging roller positioned adjacent to the image carrier in a non-contact manner with a spacer belt interposed therebetween, and charges the surface of the image carrier by applying DC and AC voltages in a superimposed manner to the charging roller.

[0096] Exposure Process and Exposure Methods

[0097] The above exposure process is a process of exposing the surface of the charged image carrier, and is performed by the above exposure means. For example, the above exposure can use the above exposure means to expose the surface of the image carrier to generate an image. The optical system in the above exposure is roughly divided into an analog optical system and a digital optical system. The above analog optical system is an optical system that directly projects an original document onto the surface of the above image carrier through an optical system. The above digital optical system is an optical system that receives image information as an electrical signal, converts the above electrical signal into an optical signal, and exposes the image carrier to form an image.

[0098] As the above exposure means, as long as it can expose the charged above image carrier to form an electrostatic latent image, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, various exposure devices such as a copying optical system, a rod lens array system, a laser optical system, a liquid crystal shutter optical system, and an LED optical system can be cited. In addition, in the present invention, a light backside method of exposing in an image manner from the backside of the image carrier can also be used.

[0099] <Development process and development means>

[0100] The above development process is a process of developing the above electrostatic latent image into the above toner image, and is performed by the above development means. As the above development means, as long as it can develop the above electrostatic latent image into a toner image, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, a development means having at least a developer that houses the above toner and can impart the above toner to the above electrostatic latent image in a contact or non-contact manner can be cited. The above developer can be either a dry development method or a wet development method. In addition, it can be either a monochromatic developer or a multicolor developer. For example, a developer including a stirrer that frictions and stirs the above toner to charge it and a rotatable magnetic roller can be cited. In the above developer, for example, the above toner and a carrier as needed are mixed and stirred, and the above toner is charged by the friction at this time and is held in an upright state on the surface of the rotating above magnetic roller to form a magnetic brush. Since the above magnetic roller is disposed near the above image carrier, a part of the above toner that constitutes the above magnetic brush formed on the surface of the above magnetic roller moves to the surface of the above image carrier by the electrostatic attraction of the above electrostatic latent image. As a result, the above electrostatic latent image is developed by the above toner, and a toner image is formed on the surface of the above image carrier. The toner housed in the above developer can be a developer including the above toner. As the above developer, it can be either a single-component developer or a two-component developer. In addition, the above toner can also be used as a single-component magnetic toner or a non-magnetic toner that does not use a carrier.

[0101] As a developing method, a pre-mixed developing method in which a pre-mixed developer obtained by premixing a toner and a carrier is replenished may also be adopted. In the pre-mixed developing method, the amount of the carrier increased in the developing device is discharged as the remaining developer. Thus, the developer in the developing device is gradually updated. As a result, it is possible to extend the replacement cycle associated with the deterioration of the developer or save the time for replacing the developer.

[0102] <Transferring Step and Transferring Means>

[0103] The above-mentioned transferring step is a step of transferring the above-mentioned toner image onto a recording medium, and is performed by a transferring means. As the above-mentioned transferring step, it preferably includes, for example, a primary transferring step of transferring the above-mentioned toner image onto the surface of the above-mentioned intermediate transfer body to form a composite transfer image using the intermediate transfer body, and a secondary transferring step of transferring the above-mentioned composite transfer image onto the recording medium. As the above-mentioned transferring step, as long as it can transfer the above-mentioned toner image onto the recording medium, there is no particular limitation, and it can be appropriately selected according to the purpose. It preferably has a primary transferring means for transferring the above-mentioned toner image onto the surface of the above-mentioned intermediate transfer body to form a composite transfer image, and a secondary transferring means for transferring the above-mentioned composite transfer image onto the recording medium. As the above-mentioned primary transferring means and the above-mentioned secondary transferring means, for example, it is preferably provided with at least a transferrer that causes the above-mentioned toner image formed on the surface of the above-mentioned image carrier to be peeled off and charged onto the recording medium. There is no particular limitation on the above-mentioned transferrer, and it can be appropriately selected according to the purpose. For example, there may be mentioned a corona discharge transferrer by corona discharge, a transfer belt, a transfer roller, a pressure transfer roller, an adhesion transferrer, etc. The above-mentioned transferrer may be one or two or more.

[0104] As the above-mentioned recording medium, as long as it can transfer the unfixed toner image after development, there is no particular limitation, and it can be appropriately selected according to the purpose. Typically, it is plain paper, and for example, a PET substrate for OHP may also be used.

[0105] <Fixing Step and Fixing Means>

[0106] The above fixing process is a process for fixing the toner image transferred onto the above recording medium, and is carried out by the above fixing means. In addition, in the case of using two or more colors of toner, fixing can be carried out each time the toner of each color is transferred onto the recording medium, or fixing can be carried out in a state where the toner of all colors is transferred onto the recording medium and laminated. As the above fixing means, as long as it can fix the toner image transferred onto the above recording medium, there is no particular limitation, and it can be appropriately selected according to the purpose, and a thermal fixing method using known heating and pressing means can be adopted. As the above heating and pressing means, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, a combination of a heating roller and a pressing roller, a combination of a heating roller, a pressing roller, and an endless belt, etc. can be cited. As the heating temperature, there is no particular limitation, and it can be appropriately selected according to the purpose, and preferably 80°C to 200°C. In addition, if necessary, a known light fixing device can also be used together with the above fixing means.

[0107] <Cleaning Process and Cleaning Means>

[0108] Here, an example of the cleaning blade of the present invention will be described with reference to the accompanying drawings. In addition, in each figure, the same reference numerals are given to the same structural parts, and repeated descriptions thereof may sometimes be omitted. In addition, the number, position, shape, etc. of the following constituent parts are not limited to the present embodiment, and appropriate numbers, positions, shapes, etc. can be selected when implementing the present invention.

[0109] The line pressure exerted by the above blade base of the cleaning blade of the present invention on the surface of the above image carrier is not particularly limited and can be appropriately selected according to the purpose. It is preferably 10 [N / m] or more and 100 [N / m] or less, and more preferably 10 [N / m] or more and 50 [N / m] or less. When the above line pressure is 10 [N / m] or more and 100 [N / m] or less, it is difficult for poor cleaning to occur where the above toner leaks through between the above contact portion and the above image carrier, and the warping of the above elastomer can be easily suppressed. In addition, the above line pressure can be measured, for example, using a measuring device equipped with a small compression type load cell manufactured by Kyowa Electronic Instruments Co., Ltd.

[0110] The angle formed between the tangent of the above image carrier at the position where the above contact portion of the above blade base of the cleaning blade of the present invention abuts and the front end surface of the free end of the above blade base (hereinafter referred to as "cleaning angle") is not particularly limited and can be appropriately selected according to the purpose. It is preferably 65° or more and 85° or less. When the above cleaning angle is 65° or more and 85° or less, the occurrence of warping of the above blade base can be easily suppressed, and the occurrence of poor cleaning can be easily reduced.

[0111] <Other Processes and Other Means>

[0112] As the above-described other processes, for example, there may be listed a charge removal process, a recovery process, a control process, etc. As the above-described other means, for example, there may be listed a charge removal means, a recovery means, a control means, etc.

[0113] (Charge removal process and charge removal means)

[0114] The above-described charge removal process is a process of removing charge by applying a charge removal bias voltage to the image carrier, and can be performed by the above-described charge removal mechanism. As the above-described charge removal means, as long as it can apply a charge removal bias voltage to the above-described image carrier, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, a charge removal lamp, etc., can be cited.

[0115] (Recovery process and recovery means)

[0116] The above-described recovery process is a process of recovering the toner removed by the above-described cleaning process into the above-described developing unit, and can be performed by the above-described recovery unit. There is no particular limitation on the above-described recovery mechanism, and it can be appropriately selected according to the purpose. For example, a known conveyance mechanism, etc., can be cited.

[0117] (Control process and control means)

[0118] The above-described control process is a process of controlling the above-described respective processes, and can be performed by a control means. As the above-described control means, as long as it can control the operations of the above-described respective processes, there is no particular limitation, and it can be appropriately selected according to the purpose. For example, a sequencer, a computer, etc., can be cited.

[0119] Here, an example of the image forming apparatus of the present invention will be described with reference to the drawings.

[0120] Figure 4 Shown is a schematic cross-sectional view of an image forming apparatus according to an embodiment of the present invention.

[0121] Figure 4 The shown image forming apparatus 500 includes four image forming units 1Y, 1C, 1M, and 1K for yellow, magenta, cyan, and black (hereinafter sometimes referred to as Y, C, M, and K). As the image forming substances for forming images, they use Y, C, M, and K toners of different colors, but the other configurations are the same.

[0122] Above the four image forming units 1Y, 1C, 1M, and 1K, a transfer unit 60 having an intermediate transfer belt 14 as an intermediate transfer body is disposed. The toner images of respective colors formed on the surfaces of the image carriers 3Y, 3C, 3M, and 3K (to be described in detail later) provided in the respective image forming units 1Y, 1C, 1M, and 1K are overlapped and transferred onto the surface of the intermediate transfer belt 14.

[0123] Furthermore, an optical writing unit 40 is disposed below the four imaging units 1Y, 1C, 1M, and 1K. As a means of forming an electrostatic latent image, the optical writing unit 40 emits a laser beam L based on image information and irradiates the image carriers 3Y, 3C, 3M, and 3K of each imaging unit 1Y, 1C, 1M, and 1K. This forms electrostatic latent images for Y, C, M, and K on the image carriers 3Y, 3C, 3M, and 3K. Furthermore, the optical writing unit 40 polarizes the laser beam L emitted by the light source using a polygonal mirror 41 driven by a motor, and simultaneously irradiates the laser beam L onto the image carriers 3Y, 3C, 3M, and 3K via multiple optical lenses and reflective mirrors. Light scanning using an LED array may also be employed in place of the above configuration.

[0124] Below the optical writing unit 40, the first paper feed cassette 151 and the second paper feed cassette 152 are arranged overlapping in the vertical direction. In each of these paper feed cassettes, recording media P are stored in the form of a plurality of overlapping paper bundles. The first paper feed roller 151a and the second paper feed roller 152a are respectively in contact with the topmost recording medium P. When the first paper feed roller 151a is driven by the drive means, Figure 4 When the first paper feed cassette 151 is driven in the counterclockwise direction, the uppermost recording medium P in the first paper feed cassette 151 is directed toward the Figure 4 The paper feeding path 153 provided in the middle right side in a manner extending in the vertical direction is discharged. In addition, when the second paper feeding roller 152a is driven to Figure 4 When the second paper feed cassette 152 is driven to rotate counterclockwise, the uppermost recording medium P in the second paper feed cassette 152 is discharged to the paper feed path 153 .

[0125] A plurality of conveying roller pairs 154 are provided in the paper feeding path 153. The recording medium P fed into the paper feeding path 153 is sandwiched between the rollers of the conveying roller pairs 154 and is moved from the paper feeding path 153 to the recording medium P. Figure 4 Transport from the lower middle side to the upper side.

[0126] A registration roller pair 55 is disposed at the downstream end of the paper feed path 153 in the conveying direction. After the recording medium P conveyed from the conveying roller pair 154 is nipped between the rollers of the registration roller pair 55, the registration roller pair 55 temporarily stops the rotation of both rollers. Then, at an appropriate time, the recording medium P is delivered to the secondary transfer nip described below.

[0127] Figure 5 FIG. 1 is a schematic cross-sectional view of an example of an imaging unit in an image forming apparatus according to an embodiment of the present invention, showing Figure 4 An example of the structure of one of the four imaging units 1Y, 1C, 1M, and 1K shown.

[0128] likeFigure 5 As shown, the imaging unit 1 includes a drum-shaped image carrier 3 as an image carrier. The image carrier 3 has a drum shape, but it can be sheet-shaped or annular belt-shaped.

[0129] Around the image carrier 3, a charging roller 4, a developing device 5, a primary transfer roller 7, a cleaning device 6, a lubricant coating device 10, a charge elimination lamp, etc. are arranged. The charging roller 4 is a charging component included in a charging device as a charging means. The developing device 5 is a developing means for toner-developing the electrostatic latent image formed on the surface of the image carrier 3. The primary transfer roller 7 is a primary transfer component included in a primary transfer device, and this primary transfer device is a primary transfer means for transferring the toner image on the surface of the image carrier 3 to the intermediate transfer belt 14. The cleaning device 6 is a cleaning means for cleaning the toner remaining on the image carrier 3 after the toner image is transferred to the intermediate transfer belt 14. The lubricant coating device 10 is a lubricant coating means for coating a lubricant on the surface of the image carrier 3 after being cleaned by the cleaning device 6. The charge elimination lamp is a charge elimination means for eliminating the surface potential of the image carrier 3 after cleaning.

[0130] The charging roller 4 is arranged non-contact with the image carrier 3 at a prescribed distance and charges the image carrier 3 to a prescribed polarity and a prescribed potential. The surface of the image carrier 3 uniformly charged by the charging roller 4 forms an electrostatic latent image according to the irradiation of the laser L of the image information from the optical writing unit 40 as an electrostatic latent image forming means.

[0131] The developing device 5 has a developing roller 51 as a developer carrier. A developing bias is applied to the developing roller 51 from a power source. Inside the housing of the developing device 5, a supply screw 52 and a stirring screw 53 are provided for conveying and stirring the developer accommodated in the housing in opposite directions. In addition, a blade 54 for restricting the developer carried by the developing roller 51 is also provided. The toner in the developer stirred and conveyed by the two screws, the supply screw 52 and the stirring screw 53, is charged to a prescribed polarity. Then, the developer is sucked onto the surface of the developing roller 51, and the sucked developer is restricted by the blade 54. In the developing area facing the image carrier 3, the toner adheres to the electrostatic latent image on the image carrier 3.

[0132] The cleaning device 6 has a brush 101, a cleaning blade 62, etc. The cleaning blade 62 abuts against the image carrier 3 in a direction opposite to the moving direction of the surface of the image carrier 3. In addition, the details of the cleaning blade 62 are as described above.

[0133] The lubricant coating device 10 includes a solid lubricant 103, a lubricant compression spring 103a, etc., and uses a brush 101 as a coating brush for coating the solid lubricant 103 onto a carrier 3. The solid lubricant 103 is held by a bracket 103b and pressed toward the brush 101 side by the lubricant compression spring 103a. Then, the solid lubricant 103 is scraped off by the brush 101 that rotates in the direction of being driven to rotate relative to the rotation direction of the carrier 3, so as to coat the lubricant onto the carrier 3. By coating the lubricant on the carrier, the coefficient of friction on the surface of the carrier 3 is maintained below 0.2 during non-image formation.

[0134] The charging device is a non-contact adjacent arrangement method that brings the charging roller 4 close to the carrier 3. However, as the charging device, a known configuration such as a corona tube, a corona wire, and a solid charger (solid state charger) can also be used. Among these charging methods, in particular, the contact charging method or the non-contact adjacent arrangement method is more ideal, and has advantages such as high charging efficiency, low ozone generation amount, and miniaturization of the device.

[0135] In the light source of the laser L of the light writing unit 40 or in light sources such as electric lamps, all light emitters such as fluorescent lamps, tungsten filament lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor laser sources (LDs), and electroluminescence (EL) can be adopted.

[0136] In addition, in order to irradiate only the light in the desired wavelength region, various filters such as a sharp cut-off filter, a band-pass filter, a near-infrared cut-off filter, a dichroic filter, an interference filter, and a color temperature conversion filter can also be adopted.

[0137] Among these light sources, light emitting diodes and semiconductor lasers have high irradiation energy and long wavelength light of 600 nm or more and 800 nm or less, so they are well used.

[0138] Figure 4 The transfer unit 60 shown as a transfer means includes, in addition to the intermediate transfer belt 14, a belt cleaning unit 162, a first carriage 63, a second carriage 64, etc. In addition, it also has four primary transfer rollers 7Y, 7C, 7M, 7K, a secondary transfer support roller 66, a drive roller 67, an auxiliary roller 68, a tension roller 69, etc. The intermediate transfer belt 14 is stretched by these eight roller components and is driven to rotate along by the rotation of the drive roller 67 Figure 4It moves in a circumferential direction counterclockwise. The four primary transfer rollers 7Y, 7C, 7M, and 7K sandwich the circumferentially moving intermediate transfer belt 14 between them and the image carriers 3Y, 3C, 3M, and 3K to respectively form primary transfer clamping portions. Then, a transfer bias having a polarity opposite to that of the toner (e.g., positive) is applied to the back surface (inner circumferential surface of the loop) of the intermediate transfer belt 14. While the intermediate transfer belt 14 sequentially passes through the primary transfer clamping portions for Y, C, M, and K during its circumferential movement, the Y, C, M, and K toner images on the image carriers 3Y, 3C, 3M, and 3K are overlapped on its front surface to perform primary transfer. Thus, a four-color overlapping toner image (hereinafter, sometimes referred to as a four-color toner image) is formed on the intermediate transfer belt 14.

[0139] In addition, in the present embodiment, an elastic intermediate transfer belt may be used as the intermediate transfer belt 14. As the elastic intermediate transfer belt, for example, a belt in which a soft elastic layer is laminated on a rigid base layer that can relatively obtain flexibility can be used.

[0140] Furthermore, in order to prevent the intermediate transfer belt 14 from meandering, an anti-deviation guiding member may be provided on the inner circumferential surface of the intermediate transfer belt 14.

[0141] The secondary transfer support roller 66 and the secondary transfer roller 70 disposed outside the loop of the intermediate transfer belt 14 sandwich the intermediate transfer belt 14 therebetween to form a secondary transfer clamping portion. The registration roller pair 55 described above sends the recording medium P sandwiched between the rollers toward the secondary transfer clamping portion at a timing synchronized with the four-color toner image on the intermediate transfer belt 14. The four-color toner image on the intermediate transfer belt 14 is secondarily transferred onto the recording medium P together within the secondary transfer clamping portion under the influence of the secondary transfer electric field and the clamping pressure formed between the secondary transfer roller 70 to which the secondary transfer bias is applied and the secondary transfer support roller 66. Then, combined with the white of the recording medium P, it becomes a full-color toner image.

[0142] On the intermediate transfer belt 14 after passing through the secondary transfer clamping portion, there adheres transfer residual toner that has not been transferred to the recording medium P. This is cleaned by the belt cleaning unit 162. In addition, the belt cleaning unit 162 brings the belt cleaning blade 122a into contact with the surface of the intermediate transfer belt 14, and thereby scrapes off and removes the transfer residual toner on the intermediate transfer belt 14.

[0143] In addition, the belt cleaning unit 162 may be provided with a collecting means as needed to receive the toner and the like removed by the lubricant coating portion or the cleaning blade. As the collecting means, a disc-shaped tray or the like can be used.

[0144] The first bracket 63 of the transfer unit 60 swings at a predetermined rotation angle around the rotation axis of the auxiliary roller 68 as the solenoid is turned on and off. When the image forming apparatus 500 forms a black and white image, the first bracket 63 is driven by the solenoid to swing. Figure 4 By this rotation, the primary transfer rollers 7Y, 7C, and 7M for Y, C, and M are rotated slightly in the counterclockwise direction. Figure 4 The intermediate transfer belt 14 is driven counterclockwise, thereby separating from the image carriers 3Y, 3C, and 3M for Y, C, and M. Then, of the four imaging units 1Y, 1C, 1M, and 1K, only the imaging unit 1K for K is driven to form a black-and-white image. This prevents the components of the imaging units 1 from being wasted due to unnecessary driving of the imaging units 1 for Y, C, and M during black-and-white image formation.

[0145] exist Figure 4 A fixing unit 80 is provided above the secondary transfer nip portion in the image processing apparatus. The fixing unit 80 includes a pressure heating roller 81 having a heat source such as a halogen lamp, and a fixing belt unit 82. The fixing belt unit 82 includes a fixing belt 84 as a fixing component, a heating roller 83 having a heat source such as a halogen lamp, a tension roller 85, a driving roller 86, a temperature sensor, etc. Then, the endless fixing belt 84 is stretched along the image processing apparatus while being stretched by the heating roller 83, the tension roller 85, and the driving roller 86. Figure 4 During this circular movement, the fixing belt 84 is heated from the back side by the heating roller 83. Figure 4 The pressing and heating roller 81, which is driven to rotate in the clockwise direction, contacts the heated fixing belt 84 from its front side, where it is wound back toward the heating roller 83. This forms a fixing nip where the pressing and heating roller 81 and the fixing belt 84 contact each other.

[0146] A temperature sensor is positioned on the outside of the fusing belt 84 loop, facing the surface of the fusing belt 84 with a predetermined gap therebetween. It detects the surface temperature of the fusing belt 84 just before it enters the fusing nip. This detection result is transmitted to the fusing power supply circuit. Based on the temperature sensor's detection result, the fusing power supply circuit turns on and off the power supply to the heat source built into the heating roller 83 and the heat source built into the pressure heating roller 81.

[0147] After the recording medium P passes through the secondary transfer nip, it is separated from the intermediate transfer belt 14 and sent to the fixing unit 80. Then, the recording medium P is nipped by the fixing nip in the fixing unit 80 and is then transferred to the fixing unit 80. Figure 4 While being conveyed from the lower center side toward the upper side, the full-color toner image is fixed to the recording medium P by being heated and pressed by the fixing belt 84 .

[0148] After the recording medium P that has undergone the fixing process passes between the rollers of the paper discharge roller pair 87, it is discharged outside the image forming apparatus. A stacking portion 88 is formed on the upper surface of the frame of the main body of the image forming apparatus 500, and the recording media P discharged outside the image forming apparatus through the paper discharge roller pair 87 are sequentially stacked in the stacking portion 88.

[0149] Above the transfer unit 60, four toner cartridges 100Y, 100C, 100M, and 100K for accommodating Y, C, M, and K toners are provided. The Y, C, M, and K toners in the toner cartridges 100Y, 100C, 100M, and 100K are appropriately supplied to the developing devices 5Y, 5C, 5M, and 5K of the image forming units 1Y, 1C, 1M, and 1K. These toner cartridges 100Y, 100C, 100M, and 100K can be installed on or detached from the main body of the image forming apparatus independently of the image forming units 1Y, 1C, 1M, and 1K.

[0150] Next, the image forming operation in the image forming apparatus 500 will be described.

[0151] First, when a signal to execute printing is received from the operation unit or the like, a prescribed voltage or current is sequentially applied to the Figure 5 shown charging roller 4 and developing roller 51 at prescribed timings. Similarly, in the Figure 4 shown light writing unit 40 and light sources such as the erasing lamp, a prescribed voltage or current is also sequentially applied at prescribed timings. Additionally, in synchronization with this, the image carriers 3, 3Y, 3C, 3M, and 3K are rotationally driven in the Figure 4 and 5 arrow directions by the image carrier drive motor as a driving means.

[0152] When the image carrier 3 rotates in the Figure 5 arrow direction, first, the surface of the image carrier 3 is uniformly charged to a prescribed potential by the charging roller 4. Then, a laser beam L corresponding to the image information is irradiated from the optical writing unit 40 onto the image carrier 3, and the portion of the surface of the image carrier 3 irradiated by the laser beam L is discharged, thereby forming an electrostatic latent image.

[0153] The surface of the image carrier 3 on which the electrostatic latent image is formed slides and rubs against the magnetic brush of the developer formed on the developing roller 51 at the opposing portion of the developing device 5. At this time, the negatively charged toner on the developing roller 51 moves toward the electrostatic latent image side by a prescribed developing bias applied to the developing roller 51 and is toner-imaged (developed). In each of the Figure 4 shown image forming units 1Y, 1C, 1M, and 1K, the same operations as those in Figure 5The imaging unit 1 performs the same imaging process, and toner images of respective colors are formed on the surfaces of the respective image carriers 3Y, 3C, 3M, and 3K of the respective imaging units 1Y, 1C, 1M, and 1K.

[0154] In this way, in the image forming apparatus 500, the electrostatic latent image formed on the image carrier 3 is reversely developed by the developing device 5 using toner charged to a negative polarity. In the present embodiment, an example of a non-contact charging roller method using N / P (negative-positive: toner adheres to a low potential portion) has been described, but it is not limited thereto.

[0155] The toner images of respective colors formed on the surfaces of the respective image carriers 3Y, 3C, 3M, and 3K are sequentially primary transferred in such a manner as to overlap on the surface of the intermediate transfer belt 14. Thus, a four-color toner image is formed on the intermediate transfer belt 14.

[0156] The four-color toner image formed on the intermediate transfer belt 14 is transferred onto the recording medium P, which is supplied from the first paper feed cassette 151 or the second paper feed cassette 152, and is supplied to the secondary transfer nip portion through between the rollers of the registration roller pair 55. At this time, the recording medium P is temporarily stopped in a state of being held by the registration roller pair 55, and is supplied to the secondary transfer nip portion after being synchronized with the leading edge of the image on the intermediate transfer belt 14. The recording medium P onto which the toner image has been transferred is separated from the intermediate transfer belt 14 and is conveyed to the fixing unit 80. Then, the recording medium P onto which the toner image has been transferred passes through the fixing unit 80. As a result, the toner image is fixed on the recording medium P under the action of heat and pressure, and the recording medium P on which the toner image has been fixed is discharged outside the image forming apparatus 500 and is stacked in the stacking portion 88.

[0157] On the other hand, in the secondary transfer nip portion, the surface of the intermediate transfer belt 14 after transferring the toner image onto the recording medium P is cleaned of the transferred residual toner on the surface by the belt cleaning unit 162.

[0158] In addition, in the primary transfer nip portion, the surface of the image carrier 3 after transferring the toner images of respective colors onto the intermediate transfer belt 14 is cleaned of the residual toner after transfer by the cleaning device 6, is coated with a lubricant by the lubricant coating device 10, and is then discharged of electricity by the discharge lamp.

[0159] As Figure 5As shown, the imaging unit 1 of the image forming apparatus 500 houses an image carrier 3, a charging roller 4 as a processing means, a developing device 5, a cleaning device 6, a lubricant coating device 10, etc. in a housing 2. Then, the imaging unit 1 can be integrally attached and detached from the main body of the image forming apparatus 500 as a processing cartridge. In the image forming apparatus 500, the imaging unit 1 replaces the image carrier 3 and the processing means integrally as a processing cartridge, but it may also be configured to be updated in units of the image carrier 3, the charging roller 4, the charging roller cleaner 8, the developing device 5, the cleaning device 6, the lubricant coating device 10, etc.

[0160]

Embodiment

[0161] Hereinafter, embodiments and reference examples of the present invention will be described, but the present invention is not limited to these embodiments. Here, "parts" means "parts by mass" unless otherwise specified.

[0162] In addition, the following will describe Figure 3 an embodiment in which the cleaning blade base shown is composed of an elastic edge layer and a base layer.

[0163] (Preparation of Particle Dispersion for Coating Layer Formation)

[0164] - Preparation of Particle Dispersion A -

[0165] 6.8 parts of polytetrafluoroethylene (PTFE) fine powder (TF9201Z, manufactured by 3M Company, volume average particle diameter 200 nm) as particles, 0.2 parts of a terpolymer of vinylidene fluoride (VdF), hexafluoropropylene (HFP), and tetrafluoroethylene (TFE) as a binder component, and 93.0 parts of 1,1,2,2 - tetrafluoroethyl 2,2,2 - trifluoroethyl ether (HFE - 347, manufactured by Tokyo Chemical Industry Co., Ltd.) as a fluorine - based dispersion solvent are placed in a helical tube and stirred with a stirrer or the like to prepare [Particle Dispersion A].

[0166] - Preparation of Particle Dispersion B -

[0167] 6.9 parts of polytetrafluoroethylene (PTFE) fine powder (TF9201Z, manufactured by 3M Company, volume average particle diameter 200 nm) as particles, 0.1 parts of a terpolymer of VdF - HFP - TFE as a binder component, and 93.0 parts of 1,1,2,2 - tetrafluoroethyl 2,2,2 - trifluoroethyl ether (HFE - 347, manufactured by Tokyo Chemical Industry Co., Ltd.) as a fluorine - based dispersion solvent are placed in a helical tube and stirred with a stirrer or the like to prepare [Particle Dispersion B].

[0168] - Preparation of Particle Dispersion C -

[0169] 5.8 parts of polytetrafluoroethylene (PTFE) fine powder (TF9201Z, manufactured by 3M Company, volume average particle diameter 200 nm) as particles, 1.2 parts of a terpolymer of VdF-HFP-TFE as a binder component, and 93.0 parts of 1,1,2,2-tetrafluoroethyl 2,2,2-trifluoroethyl ether (HFE-347, manufactured by Tokyo Chemical Industry Co., Ltd.) as a fluorine-based dispersion solvent were placed in a helical tube and stirred with a stirrer or the like to prepare [Particle Dispersion C].

[0170] - Preparation of Particle Dispersion D -

[0171] 97.0 parts of an aqueous dispersion of polymethyl methacrylate (PMMA) (MX100W, manufactured by Nippon Shokubai Co., Ltd., volume average particle diameter: 150 nm) as particles and 3.0 parts of polyvinyl butyral (PVB) (S-Lec KW-10, manufactured by Sekisui Chemical Co., Ltd., degree of acetalization: 9 ± 2 mol%) as a binder component were placed in a helical tube and stirred with a stirrer or the like to prepare [Particle Dispersion D].

[0172] - Preparation of Particle Dispersion E -

[0173] 95.0 parts of an aqueous dispersion of polymethyl methacrylate (PMMA) (MX100W, manufactured by Nippon Shokubai Co., Ltd., volume average particle diameter 150 nm) as particles and 5.0 parts of polyvinyl alcohol (PVA) resin (Poval JP-03, manufactured by Nippon Vinyils Kabushiki Kaisha, saponification degree 88 ± 2 mol%) as a binder component were placed in a helical tube and stirred with a stirrer or the like to prepare [Particle Dispersion E].

[0174] <Example 1>

[0175] (Fabrication of the Blade Substrate in the Cleaning Blade)

[0176] The edge layer and the base layer used polyurethane elastomer sheets obtained by centrifugal forming, curing, and post-crosslinking. In addition, the average thickness and the Martens hardness (HM) in the above-mentioned edge layer and the above-mentioned base layer are as follows.

[0177] Average thickness: 2.0 [mm]

[0178] Martens hardness (HM) of the edge layer: 0.5 [N / mm 2

[0179] Martens hardness (HM) of the base layer: 1.1 [N / mm 2

[0180] ​​The blade base is fabricated by bonding the above-mentioned edge layer and the above-mentioned base layer. Additionally, the above-mentioned blade base is bonded to a metal plate.

[0181] - Impregnation -

[0182] One end face used as the front end of the above-mentioned cleaning blade in the circumferential side (hereinafter, sometimes referred to as the cleaning blade front end face) is pulled up in the above-mentioned particle dispersion A at a depth of 2 [mm] from the horizontal plane to the cleaning blade front end face at a pulling speed of 1 [mm / s]. In order to collect the PTFE particles required for the cleaning function into the portion including the above-mentioned contact edge in the above-mentioned cleaning blade front end face, as Figure 6 shown, by tilting approximately 45° and drying at room temperature (25 °C) for 30 minutes, the cleaning blade of Example 1 is fabricated.

[0183] <Examples 2 to 7, Comparative Examples 1 to 3>

[0184] Except that the type of the particle dispersion, the Martens hardness of the base layer, and the average thickness of the coating layer in Example 1 are changed as shown in Table 1, the cleaning blades of Examples 2 to 7 and Comparative Examples 1 to 3 are fabricated in the same manner as in Example 1.

[0185] In addition, the thickness of the above-mentioned coating layer is controlled by the pulling speed during impregnation. As the pulling speed increases, the thickness increases.

[0186] In addition, Comparative Example 1 is a cleaning blade having a blade base without a coating layer.

[0187] <Assembly of the image forming apparatus>

[0188] The cleaning blades obtained in Examples 1 to 7 and Comparative Examples 1 to 3 are installed on the image carrier unit of a color multifunctional peripheral device (imagio MPC4500, manufactured by Ricoh Company, Ltd.) (a configuration similar to the image forming apparatus 500 shown), and the image forming apparatus is assembled. In addition, the cleaning blade is installed on the image forming apparatus such that the line pressure is 20 g / cm and the cleaning angle is 81°. Figure 4

[0189] <Measurement of the maximum penetration depth hmax of the indenter>

[0190] The maximum penetration depth hmax of the indenter of the above-mentioned edge layer of the cleaning blades obtained in Examples 1 to 7 and Comparative Examples 1 to 3 is measured. As the measurement method of the above-mentioned hmax, the measurement method described in the above-mentioned item of "Measurement of the maximum penetration depth hmax of the indenter" is adopted. The values of hmax shown in Table 1 represent the median values of the values measured at 4 to 6 points at each measurement position.

[0191] ​<Measurement of Martens hardness>

[0192] Measure the Martens hardness of the above-mentioned base layer of the cleaning blade obtained in Measurement Examples 1 to 7 and Comparative Examples 1 to 3. As the measurement method of the above-mentioned Martens hardness (HM), the measurement conditions are the same as those in the measurement of the above-mentioned "maximum penetration depth hmax of the indenter". The results are shown in Table 1. In addition, as the measurement position of the Martens hardness in the above-mentioned base layer, it is a distance of 100 [μm] from the end of the above-mentioned base layer. In addition, the above-mentioned Martens hardness represents the median value of the values measured at 4 to 6 points at each measurement position.

[0193] <Measurement of the average thickness in the coating layer>

[0194] Measure the average thickness of the above-mentioned coating layer in the cleaning blades obtained in Measurement Examples 1 to 7 and Comparative Examples 1 to 3. The results are shown in Table 1. As the measurement method of the above-mentioned average thickness, it can be measured by scraping off a part of the above-mentioned coating layer with a spatula or cotton swab, etc., and using a contact surface roughness meter (Surftest SJ-500: manufactured by Mitutoyo) for shape measurement.

[0195] <Evaluation of torque rise rate>

[0196] Use the above image forming apparatus to output under the following conditions, and measure the change rate of the driving torque rise of the image carrier. After output, observe the front end of the cleaning blade with a laser microscope (LEXTOLS 4500, manufactured by Olympus Corporation), and evaluate the torque rise rate based on the following evaluation criteria. The evaluation results are shown in Tables 1 to 3. In addition, "initial stage" in the evaluation criteria refers to the period from the output of the 1st to the 500th sheets.

[0197] Environment: 23°C / 45% RH

[0198] Paper passing condition: white paper chart

[0199] Number of output sheets: 5000 sheets (A4 size, horizontal)

[0200] - Evaluation criteria -

[0201] ◎: The change rate of torque rise is within 50% relative to the initial stage, and there is no stop of the image carrier due to the driving torque rise. Further, when observing the front end of the cleaning blade after output, there is no sign of warping at all.

[0202] ○: The change rate of torque rise is within 50% relative to the initial stage, and there is no stop of the image carrier due to the driving torque rise. However, although there is a sign of warping when observing the front end of the cleaning blade after output, since it is not at the level of toner leakage, there will be no problem in actual use.

[0203] ×: When the image carrier stops due to torque increase and the front end of the cleaning blade is observed after output, there are raised traces of toner leakage, which is a problem in actual use.

[0204] <Image quality evaluation (cleanliness)>

[0205] Using the above image forming apparatus, output is performed under the following conditions. Then, the front end of the cleaning blade and the surface of the image carrier are observed with a laser microscope (LEXTOLS4500, manufactured by Olympus Corporation), and evaluation is made based on the following evaluation criteria. The evaluation results are shown in Table 1.

[0206] Environment: 27°C / 80%RH

[0207] Paper passing condition: Continuously output full solid images

[0208] Number of output sheets: 2000 sheets (A4 size, horizontal)

[0209] - Evaluation criteria -

[0210] ◎: Toner leaked due to poor cleaning cannot be visually confirmed on the printed paper or the image carrier, and even when observing the image carrier along the length direction with a microscope, toner streaks cannot be confirmed.

[0211] ○: Toner leaked due to poor cleaning cannot be visually confirmed on the printed paper or the image carrier, but when observing the image carrier along the length direction with a microscope, toner streaks can be confirmed.

[0212] ×: Toner leaked due to poor cleaning can be visually confirmed on both the printed paper and the image carrier.

[0213] Table 1

[0214]

[0215] As an embodiment of the present invention, for example, it is as follows.

[0216] (1) An image forming apparatus, comprising: an image carrier; a charging mechanism that charges the surface of the image carrier; an exposure mechanism that exposes the charged surface of the image carrier to form an electrostatic latent image; a developing mechanism that develops the electrostatic latent image into a toner image; a transfer mechanism that transfers the toner image onto a recording medium; a fixing mechanism that fixes the toner image transferred onto the recording medium, and a cleaning mechanism that abuts against the surface of the image carrier to remove residues on the surface of the image carrier, the cleaning mechanism being a cleaning blade, wherein the image forming apparatus is characterized in that the cleaning blade includes a cleaning blade base body having an elastic cleaning blade base body and a cleaning blade support member that supports the cleaning blade base body, the elastic cleaning blade base body has an edge layer and a coating layer provided on a tip ridge line portion that abuts against the image carrier, and the maximum indentation depth hmax of the indenter of a microhardness tester based on a nanoindentation hardness test at a position where the coating layer on the lower surface of the cleaning blade base body is 100 [μm] away from the tip ridge line portion toward the inside is 4.0 [μm] or more and 10.0 [μm] or less.

[0217] (2) The image forming apparatus according to (1), characterized in that: the maximum indentation depth hmax of the indenter of the microhardness tester of the coating layer in the lower surface of the cleaning blade base body is 5.5 [μm] or more and 7.5 [μm] or less.

[0218] (3) The image forming apparatus according to the above (1) or (2), characterized in that: the thickness of the coating layer in the lower surface of the cleaning blade base body is 0.5 μm or more and 10 μm or less at a position 100 μm away from the tip ridge line portion toward the inside.

[0219] (4) The image forming apparatus according to any one of the above (1) to (3), characterized in that: the coating layer is composed of particles and a resin, and the function of the resin is to serve as a bonding component between the particles and the elastic cleaning blade base body.

[0220] (5) The image forming apparatus according to any one of the above (1) to (4), characterized in that: the coating layer is a coating film composed of PTFE particles and a fluororesin, or a coating film composed of acrylic particles and a polyvinyl alcohol resin or a polyvinyl acetal resin.

[0221] (6) The image forming apparatus according to any one of the above (1) to (5), characterized in that: the cleaning blade base body is a single-layer structure of polyurethane rubber, or a laminated structure formed by laminating a plurality of polyurethane rubbers having different Shore hardnesses.

[0222] (7) The image forming apparatus according to (6) above, characterized in that: the cleaning blade base body is a single-layer structure of polyurethane rubber, and the Shore hardness of the polyurethane rubber is 0.5 [N / mm 2 or more and 2 [N / mm 2 or less.

[0223] (8) A processing cartridge, characterized by comprising: an image carrier, a charging mechanism for charging the surface of the image carrier, an exposure mechanism for exposing the charged surface of the image carrier to form an electrostatic latent image, a developing mechanism for developing the electrostatic latent image into a toner image, and at least one or more of a transfer mechanism for transferring the toner image onto a recording medium, and a cleaning mechanism that abuts against the surface of the image carrier to remove residues on the surface of the image carrier, the cleaning mechanism being a cleaning blade, wherein the processing cartridge is characterized in that the cleaning blade includes a cleaning blade base body having an elastic cleaning blade base body and a cleaning blade support member that supports the cleaning blade base body, the elastic cleaning blade base body has an edge layer and a coating layer provided on a leading edge line portion that abuts against the image carrier, and the maximum penetration depth hmax of the indenter of a microhardness tester based on a nanoindentation hardness test at a position on the coating layer of the lower surface of the cleaning blade base body that is 100 [μm] away from the leading edge line portion toward the inside is 4.0 [μm] or more and 10.0 [μm] or less.

Claims

1. An image forming apparatus, comprising: An image carrier; A charging mechanism that charges the surface of the image carrier; An exposure mechanism that exposes the charged surface of the image carrier to form an electrostatic latent image; A developing mechanism that develops the electrostatic latent image into a toner image; A transfer mechanism that transfers the toner image onto a recording medium; A fixing mechanism that fixes the toner image transferred onto the recording medium, and A cleaning mechanism that abuts against the surface of the image carrier to remove residues on the surface of the image carrier, The cleaning mechanism is a cleaning blade, The image forming apparatus is characterized in that The cleaning blade includes a cleaning blade base body having an elastic cleaning blade base body and a cleaning blade support member that supports the cleaning blade base body, The elastic cleaning blade base body has an edge layer and a coating layer provided on the leading edge line portion that abuts against the image carrier, The maximum indentation depth hmax of the indenter of the microhardness tester based on the nanoindentation hardness test at a position on the coating layer of the lower surface of the cleaning blade base body that is 100 [μm] away from the leading edge line portion toward the inside is 4.0 [μm] or more and 10.0 [μm] or less.

2. The image forming apparatus according to claim 1, characterized in that: The maximum indentation depth hmax of the indenter of the microhardness tester on the coating layer in the lower surface of the cleaning blade base body is 5.5 [μm] or more and 7.5 [μm] or less.

3. The image forming apparatus according to claim 1 or 2, characterized in that: The thickness of the coating layer in the lower surface of the cleaning blade base body is 0.5 μm or more and 10 μm or less at a position 100 μm away from the leading edge line portion toward the inside.

4. The image forming apparatus according to claim 1 or 2, characterized in that: The coating layer is composed of particles and a resin, and the function of the resin is to be a bonding component between the particles and the elastic cleaning blade base body.

5. The image forming apparatus according to claim 1 or 2, characterized in that: The coating layer is a coating film composed of PTFE particles and a fluororesin, or a coating film composed of acrylic particles and a polyvinyl alcohol resin or a polyvinyl acetal resin.

6. The image forming apparatus according to claim 1 or 2, characterized in that: The cleaning blade base body is a single-layer structure of polyurethane rubber, or a laminated structure formed by laminating a plurality of polyurethane rubbers having different Shore hardnesses.

7. The image forming apparatus according to claim 6, characterized in that: The cleaning blade base body is a single-layer structure of polyurethane rubber, and the Shore hardness of the polyurethane rubber is 0.5 [N / mm 2 or more and 2 [N / mm 2 or less.

8. A processing cartridge, characterized in that Including: At least one or more of an image carrier, a charging mechanism that charges the surface of the image carrier, an exposure mechanism that exposes the charged surface of the image carrier to form an electrostatic latent image, a developing mechanism that develops the electrostatic latent image into a toner image, and a transfer mechanism that transfers the toner image onto a recording medium, and A cleaning mechanism that abuts against the surface of the image carrier to remove residues on the surface of the image carrier, The cleaning mechanism is a cleaning blade, The processing cartridge is characterized in that, The cleaning blade includes a cleaning blade base body having an elastic cleaning blade base body and a cleaning blade support member that supports the cleaning blade base body. The elastic cleaning blade base body has an edge layer and a coating layer provided on a leading edge line portion that abuts against the image carrier. The maximum indentation depth hmax of the indenter of the microhardness tester based on the nanoindentation hardness test at a position 100 [μm] away from the leading edge line portion toward the inside of the coating layer on the lower surface of the cleaning blade base body is 4.0 [μm] or more and 10.0 [μm] or less.

Images