Cleaning blade, cleaning device, process cartridge, and image forming apparatus

Abstract

To provide a cleaning blade suppresses both permanent deformation and warpage.SOLUTION: A cleaning blade has a front face layer in contact with a member to be cleaned, a rear face layer not in contact with the member to be cleaned, and an intermediate layer provided between the front face layer and the rear face layer. The front face layer, the intermediate layer, and the rear face layer are formed of a polyurethane member. The front face layer has, at least on its surface layer, an impregnated and cured layer of an isocyanate compound. When the 100% modulus of the front face layer other than the impregnated and cured layer is defined as Mf, the 100% modulus of the intermediate layer as Mm, and the 100% modulus of the rear face layer as Mb, Mf≥1.8×Mm and Mf×1.3≥Mb≥Mf×0.7 are satisfied. The ratio of the thickness of the intermediate layer to the entire thickness of the blade is 35% or more and 50% or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a cleaning blade, a cleaning device, a process cartridge, and an image forming apparatus. [Background technology]

[0002] In electrophotographic image forming apparatuses (such as copiers, facsimiles, and printers), a toner image formed on the surface of an image carrier is transferred to the surface of a recording medium and fixed on the recording medium to form an image. An intermediate transfer belt, for example, is used to transfer the toner image to the recording medium, and a cleaning blade is used to clean the outer peripheral surface of the intermediate transfer belt.

[0003] For example, Patent Document 1 discloses "an image forming method in which at least an image bearing means is subjected to charging, image exposure, development, transfer, fixing and cleaning processes, wherein the volume average particle size of the toner used in the development process is 7 μm or less and the circularity of the toner is 0.95 or more, the cleaning process is carried out using a cleaning blade made of a plate-shaped rubber elastic body, and the cleaning blade has a three-layer structure in which elastic bodies with different elastic properties are laminated, and the layers are designated, in order from the side that contacts the image bearing means, as a contact layer, an intermediate layer and an upper layer, and the elastic properties of the contact layer and the upper layer are a rubber hardness of 75 degrees or more and 80 degrees or less and a rebound resilience at 23°C of 20% or less, and the elastic properties of the intermediate layer are a rubber hardness of 70 degrees or less and a rebound resilience at 23°C of 40% or more and 60% or less, and the ratio of the intermediate layer to the total layer thickness is 10% or more and 30% or less."

[0004] Patent Document 2 discloses a cleaning blade used in an image forming apparatus using an electrostatic transfer process, characterized in that the cleaning blade is made up of at least three layers, including a highly rigid resin support layer with an elastic layer covering the entire surface of one side and a hot melt adhesive layer covering the entire surface of the other side. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-162801 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-255800 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present disclosure is to provide a cleaning blade having a surface layer that contacts a member to be cleaned, a back layer that does not contact the member to be cleaned, and an intermediate layer provided between the surface layer and the back layer, wherein the surface layer, the intermediate layer, and the back layer are made of polyurethane materials, and at least an impregnated and cured layer of an isocyanate compound is provided on the surface layer, and wherein, when the 100% modulus of the surface layer other than the impregnated and cured layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, the cleaning blade is less susceptible to both permanent deformation and warping than cleaning blades that do not satisfy Mf≧1.8×Mm or do not satisfy Mf×1.3≧Mb≧Mf×0.7. [Means for solving the problem]

[0007] Means for solving the above problems include the following aspects. <1> a surface layer that contacts the member to be cleaned; a back surface layer that does not contact the member to be cleaned; an intermediate layer provided between the surface layer and the back layer; and the surface layer, the intermediate layer, and the back layer are made of polyurethane materials, At least the surface layer has an isocyanate compound impregnated and cured layer thereon, When the 100% modulus of the surface layer other than the impregnated hardened layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, Mf ≥ 1.8 × Mm, and Mf × 1.3 ≥ Mb ≥ Mf × 0.7 Fulfilling A cleaning blade in which the ratio of the thickness of the intermediate layer to the total thickness of the blade is 35% or more and 50% or less. <2> Mf ≥ 2.5 × Mm and Mf × 1.1 ≥ Mb ≥ Mf × 0.9 are satisfied. <1> The cleaning blade according to claim 1. <3> The ratio of the thickness of the intermediate layer to the total thickness of the blade is 40% or more and 47% or less. <1> or <2> The cleaning blade according to claim 1. <4> The 100% modulus Mf of the surface layer is 10 MPa or more and 18 MPa or less. <1> ~ <3> 10. The cleaning blade according to claim 9, <5> The 100% modulus Mf of the surface layer is 13 MPa or more and 18 MPa or less. <4> The cleaning blade according to claim 1. <6> The thickness of the intermediate layer is 0.7 μm or more and 1.0 μm or less. <1> ~ <5> 10. The cleaning blade according to claim 9, <7> The thickness of the intermediate layer is 0.85 μm or more and 1.0 μm or less. <6> The cleaning blade according to claim 1. <8> At least the surface layer of the surface layer has an impregnated and cured layer of the isocyanate compound and silicone-modified acrylic polymer. <1> ~ <7> 10. The cleaning blade according to claim 9, <9> The intermediate layer has a 100% permanent elongation of 1.0% or less. <1> ~ <8> 10. The cleaning blade according to claim 9, <10> <1> ~ <9> A cleaning device comprising the cleaning blade according to any one of claims 1 to 4. <11> <10> A process cartridge comprising the cleaning device according to claim 1, which is detachable from an image forming apparatus. <12> an image carrier; a charging device that charges the image carrier; an electrostatic latent image forming device for forming an electrostatic latent image on the charged surface of the image carrier; a developing device that develops the electrostatic latent image formed on the surface of the image carrier with toner to form a toner image; a transfer device that transfers the toner image formed on the image carrier onto a recording medium; the cleaning blade is brought into contact with the surface of the image carrier after the toner image has been transferred by the transfer device, thereby cleaning the surface. <10> a cleaning device according to An image forming apparatus comprising: [Effects of the Invention]

[0008] <1> According to the invention, there is provided a cleaning blade having a surface layer that contacts the member to be cleaned, a back layer that does not contact the member to be cleaned, and an intermediate layer provided between the surface layer and the back layer, wherein the surface layer, the intermediate layer, and the back layer are made of polyurethane materials, and at least the surface layer has an impregnated and cured layer of an isocyanate compound on its surface layer, in which, when the 100% modulus of the surface layer other than the impregnated and cured layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, the cleaning blade is provided in which both permanent deformation and warping are suppressed compared to cleaning blades that do not satisfy Mf≧1.8×Mm or do not satisfy Mf×1.3≧Mb≧Mf×0.7.

[0009] <2> According to the invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to a case in which Mf≧2.5×Mm or Mf×1.1≧Mb≧Mf×0.9 is not satisfied. <3> According to the present invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the ratio of the thickness of the intermediate layer to the total blade thickness is less than 40% or exceeds 47%.

[0010] <4> According to the invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the 100% modulus Mf of the surface layer is less than 10 MPa or exceeds 18 MPa. <5> According to the invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the 100% modulus Mf of the surface layer is less than 13 MPa or exceeds 18 MPa.

[0011] <6> According to the invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the thickness of the intermediate layer is less than 0.7 μm or more than 1.0 μm. <7> According to the invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the thickness of the intermediate layer is less than 0.85 μm or exceeds 1.0 μm.

[0012] <8> According to the invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the impregnated cured layer does not contain a silicone-modified acrylic polymer. <9> According to the invention, a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the 100% permanent elongation of the intermediate layer exceeds 1.0%.

[0013] <10> , <11> or <12> According to the invention, there is provided a cleaning device, a process cartridge, or an image forming apparatus equipped with a cleaning blade having a surface layer that contacts the member to be cleaned, a back layer that does not contact the member to be cleaned, and an intermediate layer provided between the surface layer and the back layer, wherein the surface layer, the intermediate layer, and the back layer are made of polyurethane materials, and at least the surface layer has an impregnated and cured layer of an isocyanate compound on its surface layer, wherein, compared to a cleaning blade equipped with an impregnated and cured layer other than the surface layer, the cleaning blade does not satisfy Mf≧1.8×Mm or does not satisfy Mf×1.3≧Mb≧Mf×0.7, where Mf is the 100% modulus of the surface layer, Mm is the 100% modulus of the intermediate layer, and Mb is the 100% modulus of the back layer, there is provided a cleaning device, a process cartridge, or an image forming apparatus equipped with the cleaning blade, [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram illustrating an example of an image forming apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic cross-sectional view illustrating an example of a cleaning device according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] The present embodiment, which is an example of the present disclosure, will be described below. These descriptions and examples are intended to illustrate the embodiment and are not intended to limit the present disclosure.

[0016] In the numerical ranges described in this embodiment in stages, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in the numerical ranges described in this embodiment, the upper or lower limit value of the numerical range may be replaced with the value shown in the examples. In this embodiment, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved. When the present embodiment is described with reference to the drawings, the configuration of the embodiment is not limited to the configuration shown in the drawings. Furthermore, the sizes of the components in each drawing are conceptual, and the relative size relationships between the components are not limited to these. In this embodiment, each component may contain multiple types of corresponding substances. When referring to the amount of each component in the composition in this embodiment, if multiple types of substances corresponding to each component are present in the composition, the amount refers to the total amount of the multiple types of substances present in the composition, unless otherwise specified.

[0017] <Cleaning blade> The cleaning blade according to this embodiment has a surface layer that comes into contact with the member to be cleaned, a back layer that does not come into contact with the member to be cleaned, and an intermediate layer provided between the surface layer and the back layer. The surface layer, the intermediate layer, and the back layer are made of polyurethane materials. At least the surface layer has an impregnated and cured layer of an isocyanate compound, and when the 100% modulus of the surface layer other than the impregnated and cured layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, the relationships Mf≧1.8×Mm and Mf×1.3≧Mb≧Mf×0.7 are satisfied. The ratio of the thickness of the intermediate layer to the total thickness of the blade is 35% or more and 50% or less.

[0018] The cleaning blade according to the present embodiment has the above-described structure, which suppresses both permanent deformation and warping. The reason for this is presumed to be as follows.

[0019] High-modulus single-layer blades, which have excellent tip retraction suppression and vibration stability, can become permanently deformed (i.e., worn out) when stored in a high-temperature, high-humidity environment for a long period of time while in contact with the cleaning object, which can result in poor cleaning performance. Therefore, by making the blade a two-layer structure consisting of a surface layer and a back layer, separating the functions, and using a rubber base material with low hardness (i.e., low permanent elongation) for the back layer, it is possible to improve permanent deformation (i.e., wear) while maintaining a high modulus for the surface layer that comes into contact with the member being cleaned. On the other hand, in order to further improve the wear resistance of the blade and improve stable cleaning performance under high friction environments, an impregnation treatment technique is known in which an impregnated and cured layer of an isocyanate compound is formed on the surface layer of the blade to impart lubrication function. However, when impregnation is applied to a two-layer blade, the difference in hardness (specifically, crosslink density) between the high-hardness surface layer and the low-hardness back layer causes a difference in the amount of penetration of the impregnation solution, i.e., the volume due to differences in swelling state, which can increase strain at the interface between the surface layer and back layer and cause warping.

[0020] Therefore, the cleaning blade according to this embodiment has a three-layer structure consisting of a surface layer, a back layer, and an intermediate layer. By setting the hardness (i.e., 100% modulus) of each layer within the above range, a low-hardness intermediate layer of appropriate thickness is sandwiched between the high-hardness surface layer and back layer. This suppresses permanent deformation and also suppresses warping that occurs when an isocyanate compound impregnated and cured layer is formed.

[0021] From the above, it is presumed that the cleaning blade according to this embodiment is suppressed from both permanent deformation and warping. The cleaning blade according to this embodiment also exhibits wear resistance and a stable cleaning function due to the improved lubrication function of the isocyanate compound impregnated and cured layer.

[0022] The cleaning blade according to this embodiment will be described in detail below.

[0023] (100% modulus) In the cleaning blade according to this embodiment, when the 100% modulus of the surface layer other than the impregnated hardened layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, the relationships Mf≧1.8×Mm and Mf×1.3≧Mb≧Mf×0.7 are satisfied. From the viewpoint of suppressing permanent deformation and warpage, it is preferable to satisfy Mf≧2.5×Mm and Mf×1.1≧Mb≧Mf×0.9.

[0024] Here, from the viewpoint of suppressing permanent deformation and warpage, the 100% modulus Mf of the surface layer other than the impregnated hardened layer is preferably 10 MPa or more and 18 MPa or less, more preferably 13 MPa or more and 18 MPa or less, and even more preferably 14 MPa or more and 18 MPa or less.

[0025] The 100% modulus of each layer is measured by separating the surface layer, middle layer, and back layer from the surface layer side using a laser cutter or single-edged analytical knife, and measuring at a tensile speed of 500 mm / min using a dumbbell-shaped No. 3 test piece in accordance with JIS-K6251:2010, and determining the stress at 100% strain. The measurement is performed in an environment of 23°C.

[0026] The 100% modulus of each layer can be adjusted by selecting the type and amount of each polymerization component of the polyurethane and the production conditions. Specifically, for example, the 100% modulus of each layer can be adjusted by the crosslink density of the polyurethane (more specifically, the amount of polyisocyanate).

[0027] (thickness of each layer) In the cleaning blade according to the present embodiment, the ratio of the thickness of the intermediate layer to the total thickness of the blade is 35% to 50%, preferably 40% to 47%, and more preferably 45% to 47%. By setting the thickness ratio of the intermediate layer within the above range, both permanent deformation and warping are suppressed. In order to suppress permanent deformation and warpage, the ratio of the thickness of the intermediate layer to the thickness of the front and back layers is preferably 35% to 50%, more preferably 40% to 47%.

[0028] Here, from the viewpoint of suppressing permanent deformation and warpage, the thickness of the intermediate layer is preferably 0.7 μm or more and 1.0 μm or less, and more preferably 0.85 μm or more and 1.0 μm or less. The thickness of the entire blade is preferably 1.8 μm or more and 2.05 μm or less, and more preferably 1.9 μm or more and 2.0 μm or less.

[0029] The thickness of each layer and the entire blade is measured as follows. The blade is cut in the thickness direction to obtain a sample. The cross section of the sample is observed. The thickness is measured at three points, and the arithmetic average value is used as the thickness of each layer and the entire blade.

[0030] (100% permanent elongation of middle layer) The 100% permanent elongation of the intermediate layer is preferably 2.0% or less, more preferably 1.0% or less, and even more preferably 0.5% or less. When the 100% permanent elongation of the intermediate layer is within the above range, permanent deformation is easily suppressed.

[0031] The method for measuring the 100% permanent elongation of the intermediate layer will now be described. In accordance with JIS K6273 (2018), a rectangular test piece is subjected to 100% tensile strain and left for 24 hours, and the 100% permanent elongation is calculated from the gauge length using the following formula. Formula: Ts = (L2 - L0) / (L1 - L0) x 100 Ts: Permanent elongation L0: Gauge length before pulling L1: Gauge length when pulled L2: Gauge length after pulling

[0032] The 100% permanent elongation of the intermediate layer can be adjusted by, for example, the amount of crosslinking agent, the molecular weight of the polyol, and the like.

[0033] (Structure of each layer) The surface layer, the intermediate layer, and the back layer are made of polyurethane materials. The polyurethane constituting the polyurethane member is a polyurethane obtained by polymerizing at least a polyol component and a polyisocyanate component. If necessary, the polyurethane may be a polyurethane obtained by polymerizing a resin having a functional group capable of reacting with the isocyanate group of the polyisocyanate in addition to the polyol component.

[0034] The polyurethane preferably has a hard segment and a soft segment. The terms "hard segment" and "soft segment" refer to segments in which the former is made of a material that is relatively harder than the material that constitutes the latter, and the latter is made of a material that is relatively softer than the material that constitutes the former. Examples of materials constituting the hard segments (hard segment materials) include low-molecular-weight polyol components among polyol components, resins having functional groups capable of reacting with the isocyanate groups of polyisocyanates, etc. On the other hand, examples of materials constituting the soft segments (soft segment materials) include high-molecular-weight polyol components among polyol components.

[0035] Here, the average particle size of the hard segment aggregates is preferably 1 μm or more and 10 μm or less, and more preferably 1 μm or more and 5 μm or less. By making the average particle size of the hard segment aggregates 1 μm or more, surface friction resistance is likely to be reduced, which stabilizes blade behavior and makes it easier to suppress localized wear. On the other hand, by setting the average particle size of the hard segment aggregates to 10 μm or less, the occurrence of chipping is easily suppressed.

[0036] The average particle size of the hard segment aggregates is measured as follows: Using a polarizing microscope (Olympus BX51-P), images are taken at a magnification of ×20, and the images are binarized by image processing. The particle diameters (circle-equivalent diameters) of the aggregates are measured at five points per cleaning blade (the particle diameters of five aggregates per point are measured) for 20 cleaning blades, and the average particle diameter is calculated from a total of 500 particles. The images were binarized using the image processing software OLYMPUS Stream essentials (Olympus Corporation), and the hue / saturation / brightness thresholds were adjusted so that the crystalline portion and hard segment aggregates were black and the amorphous portion (corresponding to the soft segment) was white.

[0037] Polyol component The polyol component includes a high molecular weight polyol and a low molecular weight polyol.

[0038] The polymer polyol component is a polyol having a number average molecular weight of 500 or more (preferably 500 or more and 5000 or less). Examples of the polymer polyol component include well-known polyols such as polyester polyols obtained by dehydration condensation of low molecular weight polyols and dibasic acids, polycarbonate polyols obtained by reaction of low molecular weight polyols with alkyl carbonates, polycaprolactone polyols, and polyether polyols. Commercially available polymer polyols include PLACCEL 205 and PLACCEL 240 manufactured by Daicel Corporation.

[0039] Here, the number average molecular weight is a value measured by gel permeation chromatography (GPC). The same applies hereinafter.

[0040] These polymer polyols may be used alone or in combination of two or more.

[0041] The polymerization ratio of the high molecular weight polyol component is preferably 30 mol % or more and 50 mol % or less, and more preferably 40 mol % or more and 50 mol % or less, based on the total polymerization components of the polyurethane.

[0042] The low molecular weight polyol component is a polyol having a molecular weight (number average molecular weight) of less than 500. Molecular polyols are materials that function as chain extenders and cross-linking agents.

[0043] Examples of low molecular weight polyol components include 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, and 1,20-eicosanediol. Among these, 1,4-butanediol is preferably used as the low molecular weight polyol component.

[0044] Examples of the low molecular weight polyol component include diols (2 functional), triols (3 functional), and tetraols (4 functional), which are well known as chain extenders and crosslinking agents. These polyols may be used alone or in combination of two or more.

[0045] The polymerization ratio of the low molecular weight polyol component is preferably more than 50 mol% and 75 mol% or less, more preferably 52 mol% or more and 75 mol% or less, more preferably 55 mol% or more and 75 mol% or less, and even more preferably 55 mol% or more and 60 mol% or less, based on the total polymerization components of the polyurethane.

[0046] Polyisocyanate component Examples of the polyisocyanate component include 4,4'-diphenylmethane diisocyanate (MDI), 2,6-toluene diisocyanate (TDI), 1,6-hexane diisocyanate (HDI), 1,5-naphthalene diisocyanate (NDI), and 3,3'-dimethylbiphenyl-4,4'-diisocyanate (TODI).

[0047] As the polyisocyanate component, 4,4'-diphenylmethane diisocyanate (MDI), 1,5-naphthalene diisocyanate (NDI), and hexamethylene diisocyanate (HDI) are more preferable.

[0048] These polyisocyanate components may be used alone or in combination of two or more.

[0049] The polymerization ratio of the polyisocyanate component is preferably 5 mol % or more and 25 mol % or less, and more preferably 10 mol % or more and 20 mol % or less, based on the total polymerization components of the polyurethane.

[0050] Resins with functional groups that can react with isocyanate groups The resin having a functional group capable of reacting with an isocyanate group (hereinafter referred to as "functional group-containing resin") is preferably a flexible resin, and from the viewpoint of flexibility, it is more preferably an aliphatic resin having a linear structure. Specific examples of functional group-containing resins include acrylic resins containing two or more hydroxyl groups, polybutadiene resins containing two or more hydroxyl groups, and epoxy resins containing two or more epoxy groups.

[0051] Commercially available acrylic resins containing two or more hydroxyl groups include, for example, Actflow (grades: UMB-2005B, UMB-2005P, UMB-2005, UME-2005, etc.) manufactured by Soken Chemical & Engineering Co., Ltd.

[0052] Commercially available polybutadiene resins containing two or more hydroxyl groups include, for example, R-45HT manufactured by Idemitsu Kosan Co., Ltd.

[0053] The epoxy resin having two or more epoxy groups is preferably one that is not hard and brittle like conventional general epoxy resins, but is more flexible and tougher than conventional epoxy resins. For example, in terms of molecular structure, the epoxy resin preferably has a structure (flexible skeleton) in its main chain structure that can increase the mobility of the main chain. Examples of flexible skeletons include alkylene skeletons, cycloalkane skeletons, and polyoxyalkylene skeletons, and polyoxyalkylene skeletons are particularly preferred. In terms of physical properties, epoxy resins with a lower viscosity relative to their molecular weight than conventional epoxy resins are preferred. Specifically, the weight-average molecular weight is preferably within the range of 900±100, and the viscosity at 25°C is preferably within the range of 15,000±5,000 mPa·s, and more preferably within the range of 15,000±3,000 mPa·s. Commercially available epoxy resins with these properties include, for example, EPICLON EXA-4850-150 manufactured by DIC.

[0054] The polymerization ratio of the functional group-containing resin is preferably set within a range that does not impair the properties of the cleaning blade.

[0055] Polyurethane manufacturing method The polyurethane can be produced by a general polyurethane production method such as a prepolymer method or a one-shot method. The prepolymer method is suitable for this embodiment because it can produce polyurethane with excellent abrasion resistance and chipping resistance, but the production method is not limited thereto. The cleaning blade is produced by forming the cleaning blade composition prepared by the above method into a sheet using, for example, centrifugal molding or extrusion molding, and then cutting the sheet.

[0056] Examples of catalysts used in the production of polyurethane include amine compounds such as tertiary amines, quaternary ammonium salts, and organometallic compounds such as organotin compounds. Examples of the tertiary amine include trialkylamines such as triethylamine, tetraalkyldiamines such as N,N,N',N'-tetramethyl-1,3-butanediamine, aminoalcohols such as dimethylethanolamine, ethoxylated amines, ethoxylated diamines, ester amines such as bis(diethylethanolamine) adipate, triethylenediamine (TEDA), cyclohexylamine derivatives such as N,N-dimethylcyclohexylamine, morpholine derivatives such as N-methylmorpholine and N-(2-hydroxypropyl)-dimethylmorpholine, and piperazine derivatives such as N,N'-diethyl-2-methylpiperazine and N,N'-bis-(2-hydroxypropyl)-2-methylpiperazine.

[0057] Examples of quaternary ammonium salts include 2-hydroxypropyltrimethylammonium octylate, 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) octylate, 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) octylate, DBU-oleate, DBU-p-toluenesulfonate, DBU-formate, and 2-hydroxypropyltrimethylammonium formate.

[0058] Examples of organotin compounds include dialkyltin compounds such as dibutyltin dilaurate and dibutyltin di(2-ethylhexoate), stannous 2-ethylcaproate, and stannous oleate.

[0059] Among these catalysts, the tertiary ammonium salt triethylenediamine (TEDA) is used due to its hydrolysis resistance, while quaternary ammonium salts are preferred due to their processability. Among quaternary ammonium salts, 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) octylate, 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) octylate, and DBU formate are preferred due to their high reactivity.

[0060] The catalyst content is preferably in the range of 0.0005% by mass to 0.03% by mass, and particularly preferably 0.001% by mass to 0.01% by mass, based on the total polyurethane. These may be used alone or in combination of two or more.

[0061] (Production of a three-layered blade substrate) The blade substrate having a surface layer, an intermediate layer, and a back layer before the formation of the impregnated and cured layer is produced, for example, by producing members for the surface layer, the intermediate layer, and the back layer, respectively, by the polyurethane production method described above, and then bonding the obtained members together.

[0062] (impregnated hardened layer) In the cleaning blade according to this embodiment, at least the surface layer has a layer impregnated with and cured by an isocyanate compound. The impregnated and cured layer is preferably an impregnated and cured layer of an isocyanate compound and a modified acrylic polymer (preferably a silicone-modified acrylic polymer) in order to improve the lubricating function of the blade. Here, the impregnated hardened layer may be provided on the surface layer of the entire blade, that is, on the surface layer and the back surface layer. The surface layer where the impregnated hardened layer is formed refers to the region from the surface to a depth of 100 μm.

[0063] The impregnated and cured layer is formed by, for example, impregnating the surface layer of the cleaning blade or the entire blade with an impregnation treatment liquid containing an isocyanate compound and an organic solvent, or an impregnation treatment liquid containing an isocyanate compound, a modified acrylic polymer, and an organic solvent, and curing the isocyanate compound or the isocyanate compound and the modified acrylic polymer. As a result, the impregnated hardened layer is formed integrally with the surface layer of each layer so as to gradually become looser from the surface toward the inside.

[0064] Examples of the isocyanate compound include 2,6-tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), paraphenylene diisocyanate (PPDI), 1,5-naphthalene diisocyanate (NDI), and 3,3'-dimethyldiphenyl-4,4'-diisocyanate (TODI), as well as their polymers and modified products. Examples of modified isocyanate compounds include urethane prepolymers in which an isocyanate compound is prepolymerized with a polyol.

[0065] Examples of modified acrylic polymers include silicone-modified (meth)acrylic polymers (that is, (meth)acrylic polymers having siloxane bonds) and (meth)acrylic polymers having fluorine atoms. Among these, from the viewpoint of improving the lubricating function of the blade, the modified acrylic polymer is preferably a silicone-modified (meth)acrylic polymer, and more preferably a silicone-modified acrylic polymer. Examples of silicone-modified (meth)acrylic polymers include block copolymers of (meth)acrylic acid esters and (meth)acrylic acid siloxane esters, and derivatives thereof. Examples of the (meth)acrylic polymer having a fluorine atom include a block copolymer of a (meth)acrylic acid ester and a fluorinated alkyl (meth)acrylate, and derivatives thereof. The term "(meth)acrylic" means either or both of acrylic and methacrylic.

[0066] The content of the modified (meth)acrylic polymer in the impregnation curing liquid is, for example, 8 parts by mass or more and 13 parts by mass or less, preferably 9 parts by mass or more and 13 parts by mass or less, and more preferably 10 parts by mass or more and 13 parts by mass or less, relative to 100 parts by mass of the isocyanate compound.

[0067] Examples of the organic solvent include ethyl acetate, methyl ethyl ketone (MEK), toluene, acetone, cyclohexanone, etc. Furthermore, reactive diluents such as 2-hydroxyethyl acrylate, tetrahydrofurfuryl acrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, glycidyl methacrylate, neopentyl glycol diacrylate, hexanediol diacrylate, and trimethylolpropane triacrylate may also be used as the organic solvent.

[0068] The impregnated and cured layer is formed, for example, by applying the above-mentioned impregnated and cured liquid to at least the surface layer of the cleaning blade, removing the organic solvent by drying, and then by heat treatment. The impregnation treatment is not particularly limited, and can be performed by a conventional coating method such as blade coating, wire bar coating, spray coating, dip coating, bead coating, air knife coating, curtain coating, etc. When the impregnation treatment is performed by dip coating, the immersion time can be, for example, in the range of 10 seconds to 60 seconds. Drying conditions after the impregnation treatment include, for example, a temperature of 20° C. to 30° C. and a time of 1 minute to 10 minutes, and heating conditions include, for example, a temperature of 50° C. to 80° C. and a time of 60 minutes to 90 minutes.

[0069] (Cleaning blade uses) When the cleaning blade according to the present embodiment is used to clean a member to be cleaned, the member to be cleaned is not particularly limited as long as it is a member in an image forming apparatus whose surface requires cleaning, and examples thereof include an intermediate transfer body, a charging roll, a transfer roll, a transfer material transport belt, a paper transport roll, a detoning roll that removes toner from a cleaning brush that removes toner from an image carrier, and the like, but in the present embodiment, an image carrier is particularly preferred. Note that the cleaning blade according to the present embodiment may also be used to clean a member other than a member for an image forming apparatus as the member to be cleaned.

[0070] <Cleaning device, process cartridge and image forming apparatus> The cleaning device of this embodiment is not particularly limited as long as it includes the cleaning blade of this embodiment as the cleaning blade that contacts the surface of the member to be cleaned and cleans the surface of the member to be cleaned. For example, the cleaning device may be configured such that the cleaning blade is fixed in a cleaning case having an opening on the side of the member to be cleaned, with the tip of the surface layer facing the opening, and the cleaning device includes a conveying member that guides foreign matter, such as waste toner, collected from the surface of the member to be cleaned by the cleaning blade to a foreign matter collection container. Furthermore, the cleaning device of this embodiment may include two or more cleaning blades of this embodiment.

[0071] On the other hand, the process cartridge of this embodiment is not particularly limited as long as it is equipped with the cleaning device of this embodiment as a cleaning device that contacts the surface of one or more members to be cleaned, such as an image carrier or an intermediate transfer member, and cleans the surface of the member to be cleaned. For example, it may include an image carrier and a cleaning device of this embodiment that cleans the surface of this image carrier, and be detachable from the image forming apparatus. For example, in a so-called tandem machine having image carriers corresponding to toners of each color, a cleaning device of this embodiment may be provided for each image carrier. In addition, a cleaning brush or the like may be used in addition to the cleaning device of this embodiment.

[0072] Furthermore, the image forming apparatus according to this embodiment is not particularly limited as long as it includes an image carrier, a charging device that charges the image carrier, an electrostatic latent image forming device that forms an electrostatic latent image on the surface of the charged image carrier, a developing device that develops the electrostatic latent image formed on the surface of the image carrier with toner to form a toner image, a transfer device that transfers the toner image formed on the image carrier onto a recording medium, and a cleaning device according to this embodiment that cleans the surface of the image carrier by contacting a cleaning blade with the surface after the toner image has been transferred by the transfer device.

[0073] -Specific examples of image forming devices and cleaning devices- Next, specific examples of an image forming apparatus and a cleaning device using the cleaning blade of this embodiment will be described in more detail with reference to the drawings. FIG. 1 is a schematic diagram showing an example of an image forming apparatus according to this embodiment, which is a so-called tandem type image forming apparatus. In FIG. 1, 21 denotes a main body housing, 22, 22a to 22d denote imaging units, 23 denotes a belt module, 24 denotes a recording medium supply cassette, 25 denotes a recording medium transport path, 30 denotes each photosensitive unit, 31 denotes a photosensitive drum (an example of an image carrier), 32 denotes a charging roll (an example of a charging device), 33 denotes each developing unit (an example of a developing device), 34 denotes a cleaning device (an example of a cleaning device), 35, 35a to 35d denote toner cartridges, 40 denotes an exposure unit (an example of an electrostatic latent image forming device), 41 denotes a unit case. 42 is a polygon mirror, 51 is a primary transfer device, 52 is a secondary transfer device, 53 is a belt cleaning device, 61 is a feed roll, 62 is a transport roll, 63 is an alignment roll, 66 is a fixing device, 67 is a discharge roll, 68 is a paper discharge section, 71 is a manual feed device, 72 is a feed roll, 73 is a double-sided recording unit, 74 is a guide roll, 76 is a transport path, 77 is a transport roll, 230 is an intermediate transfer belt, 231 and 232 are support rolls, 521 is a secondary transfer roll, and 531 is a cleaning blade. The unit including the primary transfer device, the secondary transfer device, and the intermediate transfer belt is an example of a transfer device.

[0074] The tandem image forming apparatus shown in FIG. 1 has four color (yellow, magenta, cyan, and black) imaging units 22 (specifically, 22a to 22d) arranged inside a main housing 21, and above them is a belt module 23 including an intermediate transfer belt 230 that is circulated and transported along the direction in which the imaging units 22 are arranged. Meanwhile, below the main housing 21 is a recording medium supply cassette 24 that contains recording media (not shown) such as paper, and a recording medium transport path 25 that serves as a transport path for the recording media from the recording medium supply cassette 24, and is arranged vertically.

[0075] In this embodiment, each image-forming unit 22 (22a to 22d) forms a toner image, for example, for yellow, magenta, cyan, or black (the arrangement is not necessarily in this order), in order from the upstream side in the circulation direction of the intermediate transfer belt 230, and is equipped with each photosensitive unit 30, each developing unit 33, and one common exposure unit 40. Here, the photosensitive unit 30 is a sub-cartridge that integrates, for example, a photosensitive drum 31, a charging device (charging roll) 32 that pre-charges the photosensitive drum 31, and a cleaning device 34 that removes residual toner from the photosensitive drum 31.

[0076] The developing unit 33 develops the electrostatic latent image formed by exposure on the charged photosensitive drum 31 by the exposure unit 40 with a corresponding color toner (negative polarity in this embodiment), and is integrated with a subcartridge consisting of the photosensitive unit 30 to form a process cartridge (a so-called customer replaceable unit). It is needless to say that the photosensitive unit 30 may be separated from the developing unit 33 to form a standalone process cartridge. In addition, in Fig. 1, reference numeral 35 (35a to 35d) denotes a toner cartridge for replenishing each color component toner to each developing unit 33 (toner replenishing path is not shown).

[0077] On the other hand, the exposure unit 40 stores, within a unit case 41, for example, four semiconductor lasers (not shown), one polygon mirror 42, an imaging lens (not shown), and mirrors (not shown) corresponding to each photosensitive unit 30, and is arranged so that the light from the semiconductor laser for each color component is deflected and scanned by the polygon mirror 42, and the light image is directed to an exposure point on the corresponding photosensitive drum 31 via the imaging lens and mirror.

[0078] In this embodiment, the belt module 23 is, for example, an intermediate transfer belt 230 stretched between a pair of support rolls (one of which is a drive roll) 231, 232, and a primary transfer device (in this example, a primary transfer roll) 51 is disposed on the back surface of the intermediate transfer belt 230 corresponding to the photosensitive drum 31 of each photosensitive unit 30, and a voltage of a polarity opposite to the charge polarity of the toner is applied to this primary transfer device 51, thereby electrostatically transferring the toner image on the photosensitive drum 31 to the intermediate transfer belt 230. Furthermore, a secondary transfer device 52 is disposed on the intermediate transfer belt 230 at a position corresponding to the support roll 232 on the downstream side of the most downstream image forming unit 22d, and performs secondary transfer (collective transfer) of the primary transfer image on the intermediate transfer belt 230 to a recording medium.

[0079] In this embodiment, the secondary transfer device 52 includes a secondary transfer roll 521 that is placed in pressure contact with the toner image bearing surface side of the intermediate transfer belt 230, and a back roll (which also serves as the support roll 232 in this example) that is placed on the back side of the intermediate transfer belt 230 and serves as an opposing electrode to the secondary transfer roll 521. For example, the secondary transfer roll 521 is grounded, and a bias of the same polarity as the charging polarity of the toner is applied to the back roll (support roll 232). Furthermore, a belt cleaning device 53 is disposed upstream of the most upstream image forming unit 22 a of the intermediate transfer belt 230 to remove residual toner from the intermediate transfer belt 230 .

[0080] Further, the recording medium supply cassette 24 is provided with a delivery roll 61 that delivers the recording medium, and a transport roll 62 that delivers the recording medium is disposed immediately behind this delivery roll 61, and a registration roll (alignment roll) 63 that supplies the recording medium to the secondary transfer region at a predetermined timing is disposed in the recording medium transport path 25 located immediately before the secondary transfer region. Meanwhile, a fixing device 66 is provided in the recording medium transport path 25 located downstream of the secondary transfer region, and a discharge roll 67 for discharging the recording medium is provided downstream of this fixing device 66, and the discharged recording medium is stored in a paper discharge section 68 formed in the upper part of the main body housing 21.

[0081] Furthermore, in this embodiment, a manual sheet feeder (MSI) 71 is provided on the side of the main body housing 21, and the recording medium on this manual sheet feeder 71 is sent out toward the recording medium transport path 25 by a delivery roll 72 and a transport roll 62. Furthermore, a double-sided recording unit 73 is attached to the main body housing 21. When a double-sided mode is selected in which images are recorded on both sides of the recording medium, this double-sided recording unit 73 reverses the discharge roll 67 of the recording medium that has already been recorded on one side, takes it inside with a guide roll 74 just before the entrance, and transports the recording medium along the internal recording medium return transport path 76 with a transport roll 77, and supplies it again to the alignment roll 63 side.

[0082] Next, the cleaning device 34 disposed in the tandem image forming apparatus shown in FIG. 1 will be described in detail. FIG. 2 is a schematic cross-sectional view showing an example of the cleaning device of this embodiment, and also shows the photosensitive drum 31, charging roll 32, and developing unit 33, which are made into a sub-cartridge together with the cleaning device 34 shown in FIG. In FIG. 2, 32 denotes a charging roll (an example of a charging device), 331 denotes a unit case, 332 denotes a developing roll, 333 denotes a toner transport member, 334 denotes a transport paddle, 335 denotes a trimming member, 341 denotes a cleaning case, 342 denotes a cleaning blade, 344 denotes a film seal, and 345 denotes a transport member.

[0083] The cleaning device 34 has a cleaning case 341 that contains residual toner and has an opening facing the photosensitive drum 31. A cleaning blade 342 that is placed in contact with the photosensitive drum 31 is attached to the lower edge of the opening of this cleaning case 341 via a bracket (not shown), while a film seal 344 that maintains an airtight space between the cleaning case 341 and the photosensitive drum 31 is attached to the upper edge of the opening. Reference numeral 345 denotes a conveying member that guides the waste toner contained in the cleaning case 341 to a waste toner container on the side.

[0084] In this embodiment, the cleaning blade of this embodiment is used as the cleaning blade 342 in all cleaning devices 34 of each imaging unit 22 (22a to 22d), and the cleaning blade 531 used in the belt cleaning device 53 may also be the cleaning blade of this embodiment.

[0085] 2, the developing unit (developing device) 33 used in this embodiment has a unit case 331 that contains a developer and has an opening facing the photosensitive drum 31. A developing roll 332 is disposed at a location facing the opening of the unit case 331, and a toner transport member 333 for stirring and transporting the developer is disposed within the unit case 331. Furthermore, a transport paddle 334 may be disposed between the developing roll 332 and the toner transport member 333. During development, the developer is supplied to the developing roll 332, and then the developer is transported to a development area facing the photosensitive drum 31 while the developer layer thickness is regulated by, for example, a trimming member 335.

[0086] In this embodiment, the developing unit 33 uses a two-component developer made up of, for example, toner and carrier, but it may also use a one-component developer made up of only toner.

[0087] Next, the operation of the image forming apparatus according to this embodiment will be described. First, each imaging unit 22 (22a to 22d) forms a monochromatic toner image corresponding to each color. The monochromatic toner images of each color are sequentially superimposed and primarily transferred onto the surface of intermediate transfer belt 230 so as to match the original document information. Next, the color toner images transferred onto the surface of intermediate transfer belt 230 are transferred onto the surface of a recording medium by secondary transfer device 52. The recording medium onto which the color toner images have been transferred is fixed by fixing device 66 and then discharged to paper discharge section 68. Meanwhile, in each of the image forming units 22 (22a to 22d), residual toner on the photosensitive drum 31 is cleaned by the cleaning device 34, and residual toner on the intermediate transfer belt 230 is cleaned by the belt cleaning device 53. During this image forming process, the remaining toner is removed by the cleaning device 34 (or the belt cleaning device 53).

[0088] The cleaning blade 342 may be fixed via a spring member instead of being directly fixed to the frame member in the cleaning device 34 as shown in FIG. [Example]

[0089] Examples of the present disclosure will be described below, but the present disclosure is not limited to the following examples. In the following description, unless otherwise specified, all "parts" and "%" are by mass.

[0090] Example 1 100 parts by mass of polycaprolactone polyol (molecular weight 2000) as a high molecular weight polyol component and 57 parts by mass of 4,4'-diphenylmethane diisocyanate (MDI: manufactured by DIC Corporation) as a polyisocyanate component were reacted at 115°C for 20 minutes. Thereafter, 6.1 parts by mass of 1,4-butanediol and 2.6 parts by mass of trimethylolpropane as low molecular weight polyol components were mixed, and the mixture was heat-cured in a mold maintained at 140°C for 40 minutes. After molding, the molded product was cut into a width of 14 mm, a thickness of 0.5 mm, and a length of 330 mm to obtain a rubber elastic body, which was used as a surface layer member and a back layer member.

[0091] A rubber elastic body was obtained in the same manner as for the surface layer member and the back layer member, except that 37 parts by mass of 4,4'-diphenylmethane diisocyanate (MDI: manufactured by DIC Corporation) was used. The obtained rubber elastic body was used as the intermediate layer member. However, the thickness of the rubber elastic body was 0.9 mm.

[0092] The intermediate layer member was sandwiched between the surface layer member and the back layer member, and the respective members were bonded together. The resulting laminated rubber elastic body was bonded to a support plate to form a blade substrate.

[0093] Eighty parts by mass of ethyl acetate as an organic solvent, 25 parts by mass of 4,4'-diphenylmethane diisocyanate (MDI: "Millionate MT" manufactured by Tosoh Corporation, melting point: 38°C) as an isocyanate compound, and 5 parts by mass of a silicone-modified acrylic polymer (8BS-9000; manufactured by Taisei Fine Chemical Co., Ltd.) as a modified acrylic polymer were dispersed and mixed in a ball mill for 5 hours to obtain an impregnation treatment solution.

[0094] With the impregnation treatment solution kept at 23° C., the blade substrate was immersed in the impregnation treatment solution for 60 seconds, and then dried for 1 minute in a room temperature (25° C.) environment. Next, the surface of the dried blade substrate was wiped with a sponge containing a small amount of toluene, and further dried for 1 minute in a 25° C. environment, and then heated for 50 minutes in an oven maintained at 25° C. to obtain a cleaning blade.

[0095] <Comparative Example 1> 100 parts by mass of polycaprolactone polyol (molecular weight 2000) as a high molecular weight polyol component and 57 parts by mass of 4,4'-diphenylmethane diisocyanate (MDI: manufactured by DIC Corporation) as a polyisocyanate component were reacted at 115°C for 20 minutes. Thereafter, 6.1 parts by mass of 1,4-butanediol and 2.6 parts by mass of trimethylolpropane as low molecular weight polyol components were mixed, and the mixture was heat-cured in a mold maintained at 140°C for 40 minutes. After molding, the molded product was cut into a width of 14 mm, a thickness of 0.5 mm, and a length of 330 mm to obtain a rubber elastic body, which was used as a surface layer member.

[0096] A rubber elastic body was obtained in the same manner as for the surface layer member, except that 37 parts by mass of 4,4'-diphenylmethane diisocyanate (MDI: manufactured by DIC Corporation) was used. The obtained rubber elastic body was used as a back layer member. However, the thickness of the rubber elastic body was 1.4 mm.

[0097] The surface layer member and the back layer member were bonded together, and the resulting laminated rubber elastic body was bonded to a support plate to form a blade substrate.

[0098] Eighty parts by mass of ethyl acetate as an organic solvent, 25 parts by mass of 4,4'-diphenylmethane diisocyanate (MDI: "Millionate MT" manufactured by Tosoh Corporation, melting point: 38°C) as an isocyanate compound, and 5 parts by mass of a silicone-modified acrylic polymer (8BS-9000; manufactured by Taisei Fine Chemical Co., Ltd.) as a modified acrylic polymer were dispersed and mixed in a ball mill for 5 hours to obtain an impregnation treatment solution.

[0099] With the impregnation treatment solution kept at 23° C., the blade substrate was immersed in the surface treatment solution for 60 seconds, and then dried for 1 minute in a room temperature (25° C.) environment. Next, the surface of the dried blade substrate was wiped with a sponge containing a small amount of toluene, and further dried for 1 minute in a 25° C. environment, and then heated for 50 minutes in an oven maintained at 25° C. to obtain a cleaning blade.

[0100] <Examples 2 to 18, Comparative Examples 2 to 8> A cleaning blade was obtained in the same manner as in Example 1, except for the following changes according to Table 1. The amount of 4,4'-diphenylmethane diisocyanate (MDI: manufactured by DIC Corporation) used in the production of components for each layer of the blade substrate Amount of silicone-modified acrylic polymer in the impregnation treatment solution Amount of 4,4'-diphenylmethane diisocyanate (MDI: "Millionate MT" manufactured by Tosoh Corporation, melting point: 38°C) in the impregnation treatment solution Amount of ethyl acetate in the impregnation solution -Thickness of each layer

[0101] <Evaluation> The cleaning blade of each example was attached to an image forming apparatus "Apeos C-8180" manufactured by Fujifilm Business Innovation Co., Ltd. as a cleaning blade for a photoreceptor. Using the image forming apparatus described above, images with an image density of 0.5% were output on 50,000 sheets of A4 paper in a room temperature, low humidity environment (21°C, 10%). The image quality and cleaning blade after output were evaluated as follows.

[0102] (permanent deformation) The image forming device with the blade and photosensitive member in contact was stored in an environment of 40°C temperature and 95% humidity for 30 days, after which the above image formation was carried out and the occurrence of filming due to the slippage of toner and external additives caused by poor cleaning was evaluated. -standard- A: Not occurred B: Some filming of external additives occurred, but at a level that is fully acceptable for practical use. C: Filming occurs, but is at an acceptable level for practical use. D: Filming occurred. Unacceptable level for practical use. E: Filming occurs frequently. Unacceptable level for practical use.

[0103] (Blade warpage) Using a laser microscope VK-9500 manufactured by Keyence Corporation, the amount of tilt between the adhesive end and the tip of the free end in the width direction of the blade was measured and evaluated. -standard- A: Less than 0.01 mm B: 0.01mm or more and less than 0.05mm (a level that is fully acceptable in actual use). C: 0.05mm or more and less than 0.07mm (acceptable level for practical use). D: 0.07mm or more and less than 1.00mm (a level that is not acceptable in actual use). E: 1.00 mm or more (a level that is not acceptable in actual use).

[0104] (Blade wear amount) The cross-sectional profile was observed using a Keyence VK-9500 laser microscope, and the depth of the worn area at the blade tip was measured. The depth of the worn area was then evaluated as the blade wear amount. -standard- A: Blade wear amount <1.7μm 2 B: 1.7 μm 2 ≦Blade wear amount≦2.0μm 2 C: 2.0 μm 2 <Blade wear amount≦2.3μm 2 D: 2.3 μm 2 <Blade wear amount≦3.0μm 2 E: 3.0 μm 2 <Blade wear amount

[0105] [Table 1-1]

[0106] [Table 1-2]

[0107] [Table 1-3]

[0108] From the above results, it is presumed that the cleaning blade of this example is more suppressed in both permanent deformation and warping than the cleaning blade of the comparative example. It is also apparent that the cleaning blade of this example exhibits wear resistance and a stable cleaning function due to the improved lubrication function provided by the isocyanate compound impregnated and cured layer.

[0109] This embodiment includes the following aspects. (((1))) a surface layer that contacts the member to be cleaned; a back surface layer that does not contact the member to be cleaned; an intermediate layer provided between the surface layer and the back layer; and the surface layer, the intermediate layer, and the back layer are made of polyurethane materials, At least the surface layer has an isocyanate compound impregnated and cured layer thereon, When the 100% modulus of the surface layer other than the impregnated hardened layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, Mf ≥ 1.8 × Mm, and Mf × 1.3 ≥ Mb ≥ Mf × 0.7 Fulfilling A cleaning blade in which the ratio of the thickness of the intermediate layer to the total thickness of the blade is 35% or more and 50% or less. (((2))) A cleaning blade according to (((1))) that satisfies Mf≧2.5×Mm and Mf×1.1≧Mb≧Mf×0.9. (((3))) The cleaning blade according to (((1))) or (((2))), wherein the ratio of the thickness of the intermediate layer to the total thickness of the blade is 40% or more and 47% or less. (((4))) The cleaning blade according to any one of (((1))) to (((3))), wherein the 100% modulus Mf of the surface layer is 10 MPa or more and 18 MPa or less. (((5))) The cleaning blade according to (((4))), wherein the 100% modulus Mf of the surface layer is 13 MPa or more and 18 MPa or less. (((6))) The cleaning blade according to any one of (((1))) to (((5))), wherein the thickness of the intermediate layer is 0.7 μm or more and 1.0 μm or less. (((7))) The cleaning blade according to (((6))), wherein the thickness of the intermediate layer is 0.85 μm or more and 1.0 μm or less. (((8))) The cleaning blade according to any one of (((1))) to (((7))), wherein at least the surface layer of the surface layer has an impregnated and cured layer of the isocyanate compound and silicone-modified acrylic polymer. (((9))) The cleaning blade according to any one of (((1))) to (((8))), wherein the intermediate layer has a 100% permanent elongation of 1.0% or less. (((10))) A cleaning device comprising the cleaning blade according to any one of (((1))) to (((9))). (((11))) A process cartridge comprising the cleaning device according to (((10))) and detachable from an image forming apparatus. (((12))) an image carrier; a charging device that charges the image carrier; an electrostatic latent image forming device for forming an electrostatic latent image on the charged surface of the image carrier; a developing device that develops the electrostatic latent image formed on the surface of the image carrier with toner to form a toner image; a transfer device that transfers the toner image formed on the image carrier onto a recording medium; the cleaning device according to (((10))), which brings the cleaning blade into contact with the surface of the image carrier after the toner image has been transferred by the transfer device to clean it; An image forming apparatus comprising:

[0110] The effects of the above embodiment are as follows. According to the invention of (((1))), there is provided a cleaning blade having a surface layer that contacts a member to be cleaned, a back layer that does not contact the member to be cleaned, and an intermediate layer provided between the surface layer and the back layer, wherein the surface layer, the intermediate layer, and the back layer are made of polyurethane materials, and at least an impregnated and cured layer of an isocyanate compound is provided on the surface layer, and in this cleaning blade, when the 100% modulus of the surface layer other than the impregnated and cured layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, both permanent deformation and warping are suppressed compared to cleaning blades that do not satisfy Mf≧1.8×Mm or do not satisfy Mf×1.3≧Mb≧Mf×0.7.

[0111] According to the invention related to (((2))), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when Mf≧2.5×Mm or Mf×1.1≧Mb≧Mf×0.9 are not satisfied. According to the invention (((3))), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the ratio of the thickness of the intermediate layer to the total blade thickness is less than 40% or more than 47%.

[0112] According to the invention related to <4)), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the 100% modulus Mf of the surface layer is less than 10 MPa or exceeds 18 MPa. According to the invention (((5))), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the 100% modulus Mf of the surface layer is less than 13 MPa or exceeds 18 MPa.

[0113] According to the invention related to (((6), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the thickness of the intermediate layer is less than 0.7 μm or exceeds 1.0 μm. According to the invention (((7))), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the thickness of the intermediate layer is less than 0.85 μm or exceeds 1.0 μm.

[0114] According to the invention (((8))), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the impregnated cured layer does not contain a silicone-modified acrylic polymer. According to the invention (((9))), a cleaning blade is provided in which both permanent deformation and warping are suppressed compared to when the 100% permanent elongation of the intermediate layer exceeds 1.0%.

[0115] According to the inventions pertaining to <10)), (((11))) or (((12))), there is provided a cleaning device, process cartridge or image forming apparatus equipped with a cleaning blade which has a surface layer that contacts a member to be cleaned, a back layer that does not contact the member to be cleaned, and an intermediate layer provided between the surface layer and the back layer, wherein the surface layer, the intermediate layer and the back layer are made of polyurethane materials, and at least the surface layer has an impregnated and cured layer of an isocyanate compound on its surface layer, and which is less prone to permanent deformation and warping than a cleaning blade equipped with a cleaning blade other than the impregnated and cured layer that does not satisfy Mf≧1.8×Mm or does not satisfy Mf×1.3≧Mb≧Mf×0.7, where Mf is the 100% modulus of the surface layer, Mm is the 100% modulus of the intermediate layer and Mb is the 100% modulus of the back layer. [Explanation of symbols]

[0116] 21 main body housing, 22, 22a to 22d imaging unit, 23 belt module, 24 recording medium supply cassette, 25 recording medium transport path, 30 photosensitive unit, 31 photosensitive drum (image carrier), 32 charging roll, 33 developing unit, 34 cleaning device, 35, 35a to 35d toner cartridge, 40 exposure unit, 41 unit case, 42 polygon mirror, 51 primary transfer device, 52 secondary transfer device, 53 belt cleaning device, 61 feed roll, 62 transport roll, 63 alignment roll, 66 fixing device, 67 discharge roll, 68 paper discharge section, 71 manual feed device, 72 feed roll, 73 double-sided recording unit, 74 guide roll, 76 transport path, 77 transport roll, 230 intermediate transfer belt, 231, 232 support roll, 331 unit case, 332 Developing roll, 333 toner transport member, 334 transport paddle, 335 trimming member, 341 cleaning case, 342, 342A, 342B, 342C cleaning blade, 344 film seal, 345 transport member, 521 secondary transfer roll, 531 cleaning blade

Claims

1. a surface layer that contacts the member to be cleaned; a back surface layer that does not contact the member to be cleaned; an intermediate layer provided between the surface layer and the back layer; and the surface layer, the intermediate layer, and the back layer are made of polyurethane materials, At least the surface layer has an isocyanate compound impregnated and cured layer thereon, When the 100% modulus of the surface layer other than the impregnated hardened layer is Mf, the 100% modulus of the intermediate layer is Mm, and the 100% modulus of the back layer is Mb, Mf≧1.8×Mm, and Mf×1.3≧Mb≧Mf×0.7 Fulfilling A cleaning blade in which the ratio of the thickness of the intermediate layer to the total thickness of the blade is 35% or more and 50% or less.

2. 2. The cleaning blade according to claim 1, wherein Mf≧2.5×Mm and Mf×1.1≧Mb≧Mf×0.9 are satisfied.

3. 2. The cleaning blade according to claim 1, wherein a ratio of the thickness of the intermediate layer to the total thickness of the blade is 40% or more and 47% or less.

4. 2. The cleaning blade according to claim 1, wherein the 100% modulus Mf of the surface layer is 10 MPa or more and 18 MPa or less.

5. 5. The cleaning blade according to claim 4, wherein the surface layer has a 100% modulus Mf of 13 MPa or more and 18 MPa or less.

6. 2. The cleaning blade according to claim 1, wherein the thickness of the intermediate layer is 0.7 [mu]m or more and 1.0 [mu]m or less.

7. 7. The cleaning blade according to claim 6, wherein the thickness of the intermediate layer is 0.85 [mu]m or more and 1.0 [mu]m or less.

8. 2. The cleaning blade according to claim 1, wherein at least the surface layer has an impregnated and cured layer of the isocyanate compound and silicone-modified acrylic polymer as an impregnated and cured layer.

9. 2. The cleaning blade according to claim 1, wherein the intermediate layer has a 100% permanent elongation of 1.0% or less.

10. A cleaning device comprising the cleaning blade according to any one of claims 1 to 9.

11. A process cartridge comprising the cleaning device according to claim 10, and being detachable from an image forming apparatus.

12. an image carrier; a charging device that charges the image carrier; an electrostatic latent image forming device for forming an electrostatic latent image on the charged surface of the image carrier; a developing device that develops the electrostatic latent image formed on the surface of the image carrier with toner to form a toner image; a transfer device that transfers the toner image formed on the image carrier onto a recording medium; the cleaning device according to claim 10, wherein the cleaning blade is brought into contact with the surface of the image carrier after the toner image has been transferred by the transfer device to clean the surface; An image forming apparatus comprising:

Images