JP2018022020A - Cleaning blade, image forming apparatus and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cleaning blade which prevents reduction in the cleaning performance that is likely to be conspicuous at the low-temperature, is excellent in the abrasion resistance, suppresses increase in the drive torque in the long period use, can maintain the stable cleaning operation that does not generate image defects due to local abrasion or the like, and can suppress filming to an image carrier surface.SOLUTION: In a cleaning blade which is constituted of strip-shaped elastic body blades, and removes powder from the surface of a cleaning object member by bringing a tip ridge part of the elastic body blade into contact with the cleaning object member, surface layer formation parts and impregnation layer formation parts formed of ultraviolet curable resin and having the higher hardness than the elastic body blade alternately exist in the blade ridge direction over the width of at least 2 mm in the blade ridge vertical direction from the tip ridge part on a blade contact surface facing the cleaning object member and the blade tip surface in parallel with the thickness direction of the elastic body blade.SELECTED DRAWING: Figure 4D

Description

  The present invention relates to a cleaning blade, an image forming apparatus using the same, and a process cartridge.

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, unnecessary transfer residual toner adhering to a surface after transferring a toner image to a transfer paper or an intermediate transfer member is cleaned as a cleaning unit. Removed by device.
As a cleaning member of this cleaning device, a member using a strip-shaped cleaning blade is known because of its simple configuration and excellent cleaning performance. This cleaning blade is made of an elastic body such as polyurethane rubber. Then, the base end of the cleaning blade is supported by a support member, the tip ridge is pressed against the peripheral surface of the image carrier, and the toner remaining on the image carrier is dammed and scraped off and removed.

  Further, in order to meet the recent demand for higher image quality, an image forming apparatus using a toner having a small particle diameter and a nearly spherical shape (hereinafter referred to as a polymerization toner) formed by a polymerization method or the like is known. This polymerized toner has characteristics such as higher transfer efficiency than conventional pulverized toner, and can meet the above requirements. However, it is difficult to remove the polymerized toner sufficiently from the surface of the image carrier using a cleaning blade, and there is a problem that cleaning failure occurs. This is because the polymer toner having a small particle size and excellent circularity passes through a slight gap formed between the blade and the image carrier.

In order to suppress such slip-through, it is necessary to increase the contact pressure between the image carrier and the cleaning blade to increase the cleaning ability. However, as described in Patent Document 1, it is known that the following problems occur.
When the contact pressure of the cleaning blade is increased, the frictional force between the image carrier 123 and the cleaning blade 62 increases as shown in FIG. 5A, and the cleaning blade 62 is pulled in the moving direction of the image carrier 123. The leading edge portion 62c of the cleaning blade 62 is turned up. When the turned cleaning blade 62 is restored to its original state against the turn, abnormal noise may occur. Further, if the cleaning is continued with the tip ridge line portion 62c turned up, as shown in FIG. 5B, the blade tip surface 62a of the cleaning blade 62 is locally removed at a location several [μm] away from the tip ridge line portion 62c. Wear will occur. If the cleaning is further continued in such a state, the local wear increases, and the leading edge portion 62c is eventually lost as shown in FIG. 5C. If the leading edge portion 62c is missing, the toner cannot be properly cleaned, resulting in poor cleaning.

Patent Document 1 includes a surface layer made of an ultraviolet curable resin harder than an elastic blade and impregnated with an ultraviolet curable resin containing a fluorine-based acrylic monomer in the vicinity of the tip ridge line portion and covering the tip ridge line portion. A cleaning blade is described.
Further, in Patent Document 2, the edge portion of the cleaning blade is processed with high hardness to suppress the turning of the blade, and the width of the high hardness processing portion is adjusted with a plurality of blade members, thereby preventing image defects caused by slipping toner. What is suppressed is described. These blade members are made of rubber members, and the processing portions of the plurality of blades are processed by impregnating the rubber members with an isocyanate compound. Further, Patent Document 3 describes that a resin material forming a fluororesin layer is filled in irregularities on the smooth surface of the blade body, and the surface roughness of the edge portion is cleaned by stick-slip operation within a specific range. Has been. According to this, it is said that it is a high-speed machine, and even if the toner used is a small particle size toner without corners, it is possible to extend the life of the photoreceptor without deteriorating the cleaning property.

  These cleaning blades have a surface layer that is harder than the elastic blades to improve the hardness of the tip ridge line portion, etc., so that the tip ridge line portion can be deformed or turned in the surface movement direction of the image carrier. Can be suppressed. In addition, even when the surface layer wears over time and the leading edge of the elastic blade is exposed, the filling portion into the elastic blade continuously contacts the surface of the image carrier, so that the elastic blade and the image carrier The frictional force generated between the body and the body can be reduced, and deformation of the ridge line portion can be suppressed. Thereby, it is said that the turning of the tip ridge line portion can be suppressed and the wear resistance of the cleaning blade can be improved, thereby preventing the cleaning failure with time.

However, conventional cleaning blades may adversely affect the output of high-definition images by increasing the drive torque of the image carrier when the cleaning blade wears over time, and further increases wear resistance and drive. Improvement of stability and suppression of poor cleaning are desired.
The present invention does not cause a decrease in cleaning ability that is easily manifested at low temperatures, has excellent wear resistance, suppresses an increase in driving torque when used over time, and does not cause image defects due to local wear or the like. An object of the present invention is to provide a cleaning blade capable of maintaining a cleaning operation that can be maintained, and capable of suppressing filming on the surface of an image carrier.

The inventors of the present invention have made extensive studies, and the surface layer forming portion made of an ultraviolet curable resin on the blade contact surface facing the member to be cleaned and the blade tip surface parallel to the thickness direction of the elastic blade, including the ridgeline of the cleaning blade And the structure of the cleaning blade which can achieve the said subject by having comprised the impregnation layer formation part which consists of an ultraviolet curable resin alternately in a blade ridgeline direction was discovered.
That is, the above problem is solved by the following invention 1).
1) A cleaning blade that is composed of a strip-shaped elastic blade, and that makes the tip edge line portion of the elastic blade abut against a moving member to be cleaned, and removes powder from the surface of the member to be cleaned. The blade contact surface facing the cleaning member and the blade tip surface parallel to the thickness direction of the elastic blade are made of an ultraviolet curable resin over a width of at least 2 [mm] in the blade ridge line vertical direction from the tip ridge line portion. A cleaning blade in which surface layer forming portions and impregnation layer forming portions having higher hardness than an elastic blade are alternately present in the blade ridge line direction.

  According to the present invention, there is no deterioration in cleaning that has been manifested in a low temperature environment, excellent wear resistance, and an increase in drive torque during use over time is suppressed, and image defects due to local wear and the like are generated. Therefore, it is possible to provide a long-life cleaning blade capable of suppressing filming on the surface of the image carrier and maintaining wear resistance in general.

1 is a schematic configuration diagram of a printer according to an embodiment of the present invention. 1 is a schematic configuration diagram of an image forming unit according to an embodiment of the present invention. Explanatory drawing for demonstrating the measuring method of the circularity of a toner. FIG. 6A is a diagram illustrating an actual toner projection shape. (B) is a figure which shows the perfect circle of the same area as the particle | grain projection area S of (a). FIG. 6 is an explanatory diagram of a state where the cleaning blade is in contact with the surface of the photoreceptor. Explanatory drawing of the repeating structure of the formation part of a surface layer of a cleaning blade contact surface, and an impregnation layer formation part. The explanatory view of the state where the surface layer and impregnation layer of the cleaning blade contact surface and the tip surface are formed in the same phase. FIG. 5 is an explanatory diagram of a state in which a cleaning blade contact surface, a surface layer on an end surface, and an impregnation layer are formed in opposite phases. Explanatory drawing which shows the impregnation depth of a cleaning blade, the thickness and formation width of a surface layer. (A) is a diagram showing a state where the cleaning blade tip ridge is turned, (b) is a diagram for explaining local wear of the cleaning blade tip surface, (c) is a state where the cleaning blade tip ridge is missing FIG.

  Hereinafter, the present invention 1) will be described in detail. In the research, the inventors further studied at least the blade contact surface including the tip ridge portion of the elastic blade and the surface layer forming portion and the impregnation layer forming portion on the tip surface. Are alternately formed in the blade ridge line direction, and by specifying the formation conditions thereof, the occurrence of defective images due to the occurrence of cleaning failures and local wear in a low temperature environment is further suppressed, and the wear resistance is further increased. It was found that a long-life cleaning blade capable of maintaining the properties can be obtained.

That is, since the following 2) to 10) are included in the embodiment of the present invention 1), these will be described together.
2) The cleaning blade according to 1), wherein the formation positions of the surface layer forming portion and the impregnation layer forming portion on the blade contact surface and the blade tip surface are in the same phase with respect to the blade ridge line direction.
3) The cleaning blade according to 1), wherein in the cleaning blade, the formation positions of the surface layer forming portion and the impregnation layer forming portion on the blade contact surface and the blade tip surface are in opposite phases with respect to the blade ridge line direction.
4) In the cleaning blade, the surface layer forming portion and the impregnation layer forming portion are alternately present with a constant width, and the sum of the width of the surface layer forming portion in the blade ridge line direction and the width of the impregnation layer forming portion on the blade contact surface. Is 3 to 5 [mm], the width of the surface layer forming portion is 2 [mm] or more, the width of the surface layer forming portion is larger than the width of the impregnation layer forming portion, and the surface layer forming portion in the direction perpendicular to the blade ridge line The cleaning blade according to any one of 1) to 3), wherein the width of the impregnated layer forming portion is 2 to 5 [mm].
5) The cleaning blade according to any one of 1) to 4), wherein the boundary between the surface layer forming portion and the impregnation layer forming portion on the blade contact surface is perpendicular to the blade ridge line.
6) In the cleaning blade, the impregnation depth from the blade tip surface of the impregnation layer forming portion on the blade tip surface is 100 to 200 [μm], and the impregnation depth from the blade contact surface of the impregnation layer forming portion on the blade contact surface. The cleaning blade according to any one of 1) to 5), having a thickness of 50 to 150 [μm].
7) In the cleaning blade, the thickness of the surface layer of the surface layer forming portion on the blade tip surface and the blade contact surface is 1.0 to 2.5 [μm]. Cleaning blade.
8) The cleaning blade further includes a second surface layer covering the surface layer forming portion and the impregnation layer forming portion on the blade tip surface and the blade contact surface, and a second surface layer on the blade tip surface and the blade contact surface. The cleaning blade according to 7), wherein the thickness of the cleaning blade is 0.5 to 1.0 [μm].
9) an image carrier, charging means for charging the surface of the image carrier, latent image forming means for forming an electrostatic latent image on the charged surface of the image carrier, and the image formed on the surface of the image carrier A developing means for developing the electrostatic latent image into a toner image, a transfer means for transferring the toner image on the surface of the image carrier to the transfer body, and abutting on the surface of the image carrier and adhering to the surface of the image carrier An image forming apparatus comprising: a cleaning unit having a cleaning blade for cleaning the transfer residual toner, wherein the cleaning blade according to any one of 1) to 8) is used as the cleaning blade.
10) A process cartridge that is detachably attached to the main body of the image forming apparatus, wherein the image carrier and the cleaning blade according to any one of 1) to 8) are integrally formed.

The cleaning blade according to the present invention is composed of a strip-shaped elastic blade, and the cleaning blade removes powder from the surface of the member to be cleaned by bringing the tip ridge line portion of the elastic blade into contact with the member to be cleaned. In the blade
From the ultraviolet curable resin over a width of at least 2 [mm] in the blade ridge line vertical direction from the tip ridge line portion of the blade contact surface facing the member to be cleaned and the blade tip surface parallel to the thickness direction of the elastic blade. The surface layer forming portion and the impregnation layer forming portion having higher hardness than the elastic blade are configured to alternately exist in the blade ridge line direction.
The hardness can be compared by Martens hardness. The Martens hardness of the surface layer forming portion and the impregnation layer forming portion when the surface layer forming portion and the impregnation layer forming portion made of an ultraviolet curable resin are formed on the elastic blade is higher than the Martens hardness of the elastic blade.
The repeated configuration of the surface layer forming part and the impregnated layer forming part suppresses local wear due to continuous occurrence of local toner slippage, which was a problem in a low temperature environment, and poor cleaning at that part. It is something that can be done.
Since the resistance to wear including local wear is increased, good cleaning properties are maintained, and as a result, filming on the image carrier is also suppressed.
In the present invention, the blade contact surface facing the member to be cleaned is a surface 62b facing the downstream side B in the traveling direction of the member to be cleaned in FIG. 4A, and is a blade parallel to the thickness direction of the elastic blade. A front end surface means the surface which opposes the advancing direction upstream side A of the to-be-cleaned member shown by 62a in FIG. 4A.

The phenomenon in which the local toner slipping occurs continuously is caused by a decrease in the elastic characteristics of the blade ridge line portion at a low temperature. For example, in the cleaning operation, deformation occurs due to toner particle slipping, and the deformation is recovered. It is considered that the toner particles continue to slip through due to the decrease in speed, and wear progresses locally in the slipping portion. On the other hand, according to the configuration of the present invention, for example, since the deformation speed and the deformation amount of the surface layer forming portion and the impregnation layer forming portion are different on the blade contact surface, the toner particles are locally slipped through. It is thought that it can be suppressed. In order to facilitate the function of recovery from deformation during slipping through continuous toner slipping in this way, it is effective to have surface layer forming portions and impregnated layer forming portions alternately on the blade tip surface. It turned out to be. In the blade ridge line, the contact surface and the tip surface are adjacent to each other, and the surface layer forming portion and the impregnation layer forming portion are in contact therewith. In this case, the surface layer forming portion and the impregnation layer are formed on the blade ridge line between the contact surface and the tip surface in the same manner as the surface layer forming portion and the impregnation layer forming portion exist alternately in the contact surface or the tip surface. It becomes the structure which a formation part exists alternately, and it can be selected whether the surface layer and the impregnation layer are formed in the same phase, or are formed in the reverse phase. By providing these layers at a specific ratio, it becomes possible to promote the recovery of deformation of the part even if the toner particles slip through suddenly. It is possible to suppress the occurrence of defective cleaning.
The repeated configuration of the surface layer forming portion and the impregnation layer forming portion on the blade contact surface is, for example, the configuration shown in FIG. 4B, and the blade contact surface, the surface layer forming portion on the blade tip surface, and the impregnation layer forming portion are As shown in FIG. 4C, the blade contact surface, the surface layer forming portion and the impregnation layer forming portion of the blade tip surface are in the same phase where the forming positions are the same in the blade ridge direction, or the blade ridge line as shown in FIG. 4D It is preferable to configure with an antiphase arrangement in which the formation position is opposite to the direction. Although all have the effect of suppressing the cleaning failure, it is more preferable that the surface layer forming portion and the impregnation layer forming portion having the configuration of FIG.
Further, it is preferable that the boundary between the surface layer forming portion and the impregnation layer forming portion on the blade contact surface is perpendicular to the blade ridge line.

It is preferable that the surface layer forming part and the impregnated layer forming part alternately exist with a constant width. In FIGS. 4C and 4D, the surface layer forming width [b] in the blade ridge line direction and the impregnating layer formation on the blade contact surface The preferable ranges of the width [c], the sum [a], and the width [d] in the ridge line vertical direction are [a]: 3 to 5 [mm], [b]: 2 [mm] or more, and [b]> [ c], [d]: 2 to 5 [mm]. In FIG. 4D, [b ′] represents the surface layer formation width in the blade ridge line direction on the blade tip surface, and [c ′] represents the impregnation layer formation width on the blade tip surface.
The formation width in the vertical direction (thickness direction) of the surface layer forming portion and the impregnation layer forming portion on the blade tip surface needs to be up to 2 [mm], but the width in the thickness direction is 2 [mm]. If it is less, the entire surface in the thickness direction may be sufficient. The formation width [d] in the direction perpendicular to the ridgeline of the surface layer forming portion and the impregnation layer forming portion on the blade contact surface needs to be at least 2 [mm] from the tip ridgeline portion, and may be larger than that. However, if it exceeds about 5 [mm], the bending of the blade is affected, and the contact state with the photosensitive member is affected, which is not preferable.
The thickness of the surface layer is preferably 1.0 to 2.5 [μm] for both the blade tip surface and the blade contact surface. When it is 1.0 [μm] or more, the stability of the blade ridge line is improved, and when it is 2.5 [μm] or less, followability to the photosensitive member is not insufficient, and cleaning failure does not occur. . In addition, adaptation of these thickness can be adjusted with each of base rubber | gum, the impregnated ultraviolet curable resin, and each of surface layer formation resin.

  The repetitive configuration of the surface layer forming part and the impregnated layer forming part first limits the formation region by a masking method that covers the surface layer non-forming part with an adhesive masking tape or the like at the time of dip coating or spray coating. Then, an impregnation treatment is performed using the surface layer forming portion as a mask, whereby a repeated configuration of the surface layer forming portion and the impregnating layer forming portion can be achieved. Such a repetitive configuration in the present invention has an effect on the occurrence of abnormal noise such as chatter and squeal, and the increase in the driving torque of the photosensitive member, which has been a problem in the past because the contact force of the blade is dispersed. It is.

  The cleaning blade in the present invention may be further provided with a second surface layer after the above-described configuration is formed, and the second surface layer is covered with at least the same formation region as the surface layer forming portion and the impregnation layer forming portion. Preferably, the thickness of the second surface layer on the blade tip surface and the blade contact surface is preferably 0.5 to 1.0 [μm]. The second surface layer can be expected to have an effect of lowering the coefficient of friction on the surface of the impregnated layer and preventing the toner from adhering to the location, and the effect is easily obtained at 0.5 [μm] or more and 1.0 [μm]. The following is preferable because followability to the photoreceptor is not insufficient.

The member to be cleaned is not particularly limited with respect to its material, shape, structure, size, etc., and can be appropriately selected according to the purpose. Examples of the shape of the member to be cleaned include a drum shape, a belt shape, a flat plate shape, and a sheet shape. There is no restriction | limiting in particular as a magnitude | size of the said member to be cleaned, Although it can select suitably according to the objective, The magnitude | size normally used is preferable.
There is no restriction | limiting in particular as a material of the said to-be-cleaned member, According to the objective, it can select suitably, For example, a metal, a plastic, a ceramic, etc. are mentioned.
The member to be cleaned is not particularly limited and can be appropriately selected according to the purpose. When the cleaning blade is applied to an image forming apparatus, for example, an image carrier (also referred to as a photosensitive member), etc. Is mentioned.
The powder is not particularly limited as long as it is an object to be removed by the cleaning blade, and can be appropriately selected according to the purpose. Examples thereof include toner, lubricant, and inorganic fine particles.

  4A to 4E are sectional views of the cleaning blade 62 in use according to an embodiment of the present invention. 4A is an explanatory view showing a state in which the cleaning blade 62 is in contact with the surface of the photosensitive member 3, and FIG. 4B is an explanatory view of a repeated configuration of a surface layer forming portion and an impregnation layer forming portion on the blade contact surface. . 4C is an explanatory view showing a state where the blade contact surface and the surface layer forming portion and impregnation layer forming portion of the blade tip surface are formed in the same phase, and FIG. 4D is a surface layer of the blade contact surface and the blade tip surface. FIG. 4E is an explanatory view showing a state where the formation portion and the impregnation layer formation portion are formed in opposite phases, and FIG. 4E is an explanatory view showing the impregnation depth of the cleaning blade, the thickness of the surface layer, and the formation width.

The cleaning blade 62 includes a strip-shaped holder 621 made of a rigid material such as metal or hard plastic, and a strip-shaped elastic blade 622. The elastic blade 622 has surface layer forming portions and impregnated layer forming portions alternately in the ridge line direction in the vicinity of the tip ridge line portion 62c.
The elastic blade 622 is fixed to one end of the holder 621 with an adhesive or the like, and the other end of the holder 621 is cantilevered by the case of the cleaning device 6.

The elastic blade 622 preferably has a high rebound resilience, such as urethane rubber, so that it can follow the eccentricity of the photosensitive member 3 and minute undulations on the surface of the photosensitive member 3.
Urethane rubber suitable for the elastic blade 622 is generally manufactured by a centrifugal molding method. The raw materials include a polyol having two or three hydroxyl groups with an OH number of 28 to 168, TDI (tolylene diisocyanate), MDI (diphenylmethane diisocyanate), IPDI (isophorone diisocyanate), HDI (hexamethylene diisocyanate), NDI. (Naphthalene diisocyanate), TODI (dimethylbiphenyl diisocyanate) and other diisocyanates, and short chains having an OH number of 950 to 1830 such as ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, glycerin, trimethylolethane, and trimethylolpropane Polyols are preferred. These are mixed as appropriate, poured into a centrifugal mold heated to 100 to 200 [° C.], demolded after a predetermined time, and placed in a hot and humid environment (for example, 30 [° C.], 85 [% RH]) for one week. After standing to stabilize the characteristics, it is cut into a predetermined shape to obtain a strip for an elastic blade.

  The elastic blade 622 may be urethane rubber having a hardness at 25 ° C. of 68 to 80 degrees (JIS A). If the hardness of the urethane rubber is 80 degrees or less, the flexibility does not become poor, and there is no possibility that the following problems will occur when the holder 621 is attached with a slight inclination. That is, the so-called uneven contact in which the contact pressure is different between the one end side and the other end side of the cleaning blade 62 is difficult, and a uniform contact pressure is obtained in the axial direction. As a result, the cleaning property does not deteriorate. On the other hand, if the hardness is 68 degrees or more, the cleaning blade 62 will not be warped when the contact pressure is set high so that even polymerized toner can be cleaned. Further, the so-called anti-hit phenomenon in which the leading edge ridge line portion 62c is lifted and the blade contact surface 62b is in contact with the photosensitive member 3 does not occur. When the stomach contact phenomenon occurs, the contact area between the cleaning blade 62 and the surface of the photosensitive member increases rapidly, so that the contact pressure is reduced even if the cleaning blade 62 is pressed with a large force, and the cleaning performance is deteriorated. End up. In particular, in the configuration having the impregnation treatment or the surface layer on the blade tip surface as in the present invention, the above phenomenon is likely to occur, and therefore it is preferably in the above range.

  The elastic blade 622 can also be a two-layer type in which two different materials are laminated. In this case as well, the hardness of the urethane rubber is preferably within the above range, but an appropriate material can be appropriately selected on the contact side and the anti-contact side. When manufacturing two or more layers of urethane, the raw materials with different mixing ratios are injected into the centrifugal mold continuously before each layer is completely cured, so that delamination does not occur. It is possible to mold.

An impregnation layer forming portion 62d impregnated with an ultraviolet curable resin monomer is formed on the blade contact surface and the blade tip surface of the elastic blade 622. The impregnation treatment on the blade contact surface and the blade tip surface may be performed by impregnating the ultraviolet curable resin monomer by spray coating or dip coating. Thereby, it can suppress that the front-end | tip ridgeline part 62c which contact | abuts deform | transforms in the photoreceptor 3 surface moving direction. Furthermore, even when the interior is exposed due to the surface layer wear over time, the deformation can be similarly suppressed by the impregnation action.
The depth of the impregnation treatment in the present invention is such that the impregnation depth from the blade tip surface is 100 to 200 [μm] in the impregnation layer forming portion on the blade tip surface, and the impregnation layer forming portion on the blade contact surface is The impregnation depth from the blade contact surface is preferably 50 to 150 [μm]. Within these ranges, it is possible to reliably suppress the occurrence of the aforementioned cleaning failure. That is, if the impregnation depth is equal to or greater than the lower limit of the above range, the toner particles are not deformed, and the clogging force does not decrease to cause a cleaning failure. Further, if the impregnation depth is not more than the upper limit of the above range, the rigidity is not increased, the adhesion to the photoreceptor is not lowered, and the cleaning failure does not occur. In addition, it is important to adjust these ranges from the balance with the formation state of the surface layer. As described in the description of the surface layer, this impregnation treatment has an effect of reducing friction with the photoconductor and suppressing an increase in photoconductor driving torque. Even when the blade edge wears and the internal structure of the tip advances and the internal structure is exposed, the impregnation treatment is performed within the above range, so that the increase in frictional force is suppressed, and the photoreceptor driving torque is reduced. The rise can be suppressed. The increase in photosensitive member drive torque induces a decrease in image quality due to jitter and misalignment in a so-called tandem type system that combines a plurality of image forming units. Decrease can be avoided. Along with the improvement of the wear resistance due to the formation of the surface layer, the maintenance of the cleaning property can be achieved comprehensively.

  In the formation of the surface layer, the surface layer 623 uses the ultraviolet curable resin monomer for the elastic blade 622 and covers the surface layer forming portion on the blade contact surface and the tip surface by spray coating or dip coating. After coating with the ultraviolet curable resin monomer, the surface layer can be cured by irradiating with ultraviolet rays. The impregnated layer forming part can be formed by performing an impregnation treatment on a portion where the surface layer is not formed by using this surface layer as a mask. After the impregnation treatment, the impregnation layer can be cured by irradiating ultraviolet rays again. it can. At this time, if the fluorine-based acrylic monomer is mixed with the impregnation material and impregnated into the elastic blade 622, the friction near the tip ridge line portion 62c can be reduced. Even when the ridge portion 62c is worn due to use over time, a processing portion is also present inside due to the impregnation treatment, so that the frictional force between the tip ridge portion 62c and the photosensitive member 3 is weakened in contact with the surface of the photosensitive member. Can do. Furthermore, even when the ridge portion is worn, it is possible to suppress deformation in the direction of movement of the photoreceptor surface. As a result, generation of chatter noise can be suppressed. Moreover, the turn of the part can be suppressed and omission of the exposed exposed part can be suppressed. Further, since the tip ridge line portion 62c is reduced in friction by impregnation with the fluorinated acrylic monomer, it is difficult to be scraped off by the photoreceptor 3, and the wear resistance of the cleaning blade 62 can be improved.

  As the fluorinated acrylic monomer, an acrylate having a perfluoropolyether skeleton and having two or more functional groups is particularly suitable. Specific examples thereof include Daikin Corporation: OPTOOL DAC-HP, DIC Corporation: RS-75, and the like.

Further, durability can be improved by impregnating with an ultraviolet curable resin monomer and irradiating with ultraviolet rays.
A possible reason for this is the possibility that the crosslink density of the rubber itself increases in a pseudo manner and the wear resistance is improved due to the formation of a UV curable resin network chain inside the rubber. In this case, the point is that the ultraviolet curable resin and the urethane rubber are hardly chemically bonded. By suppressing the reaction with the urethane rubber, it is possible to suppress the crosslink density from being increased so that it becomes a state closer to glass rather than a rubber. Thereby, it is considered that the movement of the tip ridge line portion 62c is not suppressed and the wear resistance is improved.

  The surface layer 623 covers the tip surface 62a and the blade contact surface 62b of the cleaning blade 62 by spray coating or dip coating. The surface layer 623 is preferably covered with a member having a hardness higher than that of the elastic blade 622. Whether the hardness of the surface layer is higher than that of the elastic blade can be confirmed, for example, by measuring the Martens hardness, and the hardness is obtained accurately by measuring the test force applied to the measuring indenter and the indentation depth of the indenter. be able to. Such a microhardness measurement conforms to the ISO14577 standard. A surface layer member having a high hardness is selected by separately comparing the Martens hardness of the elastic blade itself and the surface layer itself. By using a member having a hardness higher than that of the elastic blade 622, the cleaning blade 62 is less likely to be scraped off by the photosensitive member 3 than the elastic blade 622, and compared with a member that makes the elastic blade 622 contact the surface of the photosensitive member. The wear resistance of can be improved. Further, since the surface layer 623 is hard and rigid, it is difficult to be deformed, and the tip ridge line portion 62c can be prevented from being turned over.

  Further, an ultraviolet curable resin is used as a material for the surface layer 623. Thus, the surface layer 623 having a desired hardness can be obtained simply by irradiating the ultraviolet curable resin monomer attached to the tip ridge line portion 62c with ultraviolet rays, and the cleaning blade 62 can be manufactured at low cost.

  As the ultraviolet curable resin monomer, a monomer having a functional group equivalent molecular weight of 350 or less and a pentaerythritol triacrylate having 3 to 6 functional groups as a main skeleton is preferably used. If a monomer having a functional group equivalent molecular weight of 350 or less and a main skeleton of pentaerythritol triacrylate is used, the surface layer 623 will not become too fragile. When the surface layer 623 becomes brittle, the tip edge line portion 62c of the cleaning blade 62 is turned over, leading to wear of the tip surface as shown in FIG. 5B, and the cleaning performance for a long time cannot be maintained. In addition to the pentaerythritol triacrylate skeleton material, it is preferable to appropriately mix an acrylate material having a functional group equivalent molecular weight of 100 to 1000 and a functional group of 1 to 2 as the material of the surface layer 623. Thus, flexibility can be imparted to the surface layer 623, and the properties of the surface layer 623 can be adjusted in accordance with the characteristics of the machine on which the cleaning blade 62 is mounted. Therefore, it is possible to improve environmental characteristics and the like, for example, by finely adjusting the blade behavior when abnormal noise occurs in a specific environment.

  The same material can be used for all or part of the material for the surface layer 623 and the material to be impregnated. When the same material is used, an improvement in adhesiveness between the same substances can be expected, and peeling of the surface layer 623 can be suppressed.

  The image forming apparatus of the present invention includes an image carrier, a charging unit for charging the surface of the image carrier, a latent image forming unit for forming an electrostatic latent image on the charged surface of the image carrier, and the image carrier. A developing means for developing the electrostatic latent image formed on the surface to form a toner image; a transfer means for transferring the toner image on the surface of the image carrier to a transfer body; In an image forming apparatus including a cleaning unit having a cleaning blade for cleaning the transfer residual toner attached to the surface of the image carrier, the cleaning blade of the present invention is used as the cleaning blade.

As an example of an image forming apparatus to which the cleaning blade of the present invention is applied, a general electrophotographic printer (hereinafter referred to as a printer 500) will be described.
FIG. 1 is a schematic configuration diagram illustrating a printer 500. The printer 500 includes four image forming units 1Y, 1C, 1M, and 1K for yellow, cyan, magenta, and black (hereinafter referred to as Y, C, M, and K). These use Y, C, M, and K toners of different colors as image forming substances for forming an image, but the other configurations are the same.

Above the four image forming units 1, a transfer unit 60 including an intermediate transfer belt 14 as an intermediate transfer member is disposed. The toner images of the respective colors formed on the surfaces of the photoreceptors 3Y, 3C, 3M, and 3K included in the image forming units 1Y, 1C, 1M, and 1K, which will be described later, are superimposed and transferred onto the surface of the intermediate transfer belt 14. This is a configuration.
Further, an optical writing unit 40 is disposed below the four image forming units 1. The optical writing unit 40 serving as a latent image forming unit irradiates the photoconductors 3Y, 3C, 3M, and 3K of the image forming units 1Y, 1C, 1M, and 1K with laser light L emitted based on the image information. Thereby, electrostatic latent images for Y, C, M, and K are formed on the photoreceptors 3Y, 3C, 3M, and 3K. The optical writing unit 40 deflects the laser light L emitted from the light source by the polygon mirror 41 that is rotationally driven by a motor, and passes through the photosensitive members 3Y, 3C, 3M, and 3K via a plurality of optical lenses and mirrors. Is irradiated. Instead of such a configuration, one that performs optical scanning with an LED array may be employed.

  Below the optical writing unit 40, a first paper feed cassette 151 and a second paper feed cassette 152 are arranged to overlap in the vertical direction. In each of these paper feed cassettes, a plurality of transfer papers P as recording media are accommodated in a stack of paper sheets. The uppermost transfer paper P includes a first paper feed roller 151a and a first paper feed roller 151a. The two paper feed rollers 152a are in contact with each other. When the first paper feed roller 151a is rotated counterclockwise in the figure by the driving means, the uppermost transfer paper P in the first paper feed cassette 151 extends in the vertical direction on the right side of the cassette in the figure. The paper is discharged toward the paper feed path 153 arranged to exist. Further, when the second paper feed roller 152a is driven to rotate counterclockwise in FIG. 1 by the driving means, the uppermost transfer paper P in the second paper feed cassette 152 is discharged toward the paper feed path 153. Is done.

A plurality of conveying roller pairs 154 are arranged in the paper feed path 153. The transfer paper P sent into the paper feed path 153 is conveyed from the lower side to the upper side in FIG. 1 while being sandwiched between the rollers of the conveyance roller pair 154.
A registration roller pair 55 is disposed at the downstream end of the paper feed path 153 in the transport direction. The registration roller pair 55 temporarily stops the rotation of both rollers as soon as the transfer paper P sent from the conveyance roller pair 154 is sandwiched between the rollers. Then, the transfer paper P is sent out toward a secondary transfer nip described later at an appropriate timing.

FIG. 2 is a configuration diagram showing a schematic configuration of one of the four image forming units 1.
As shown in FIG. 2, the image forming unit 1 includes a drum-shaped photoconductor 3 as an image carrier. The photosensitive member 3 has a drum shape, but may be a sheet shape or an endless belt shape.
Around the photoreceptor 3, a charging roller 4, a developing device 5, a primary transfer roller 7, a cleaning device 6, a lubricant application device 10, a static elimination lamp, and the like are disposed. The charging roller 4 is a charging member provided in a charging device as a charging unit, and the developing device 5 is a developing unit that converts a latent image formed on the surface of the photoreceptor 3 into a toner image. The primary transfer roller 7 is a primary transfer member provided in a primary transfer device as a primary transfer unit that transfers a toner image on the surface of the photoreceptor 3 to the intermediate transfer belt 14. The cleaning device 6 is a cleaning unit that cleans the toner remaining on the photoreceptor 3 after the toner image is transferred to the intermediate transfer belt 14. The lubricant application device 10 is a lubricant application unit that applies a lubricant onto the surface of the photoreceptor 3 after the cleaning device 6 performs cleaning. The neutralization lamp is a neutralization unit that neutralizes the surface potential of the photoreceptor 3 after cleaning.

The charging roller 4 is arranged in a non-contact manner with a predetermined distance from the photoconductor 3, and charges the photoconductor 3 to a predetermined polarity and a predetermined potential. The surface of the photoreceptor 3 uniformly charged by the charging roller 4 is irradiated with laser light L from an optical writing unit 40 serving as a latent image forming unit based on image information, thereby forming an electrostatic latent image.
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. In the casing of the developing device 5, a supply screw 52 and a stirring screw 53 are provided for stirring the developer contained in the casing while conveying the developer in opposite directions. A doctor 54 for regulating the developer carried on the developing roller 51 is also provided. The toner in the developer stirred and conveyed by the two screws of the supply screw 52 and the stirring screw 53 is charged to a predetermined polarity. The developer is pumped up on the surface of the developing roller 51, and the pumped-up developer is regulated by the doctor 54, and the toner adheres to the latent image on the photoconductor 3 in the development area facing the photoconductor 3. .

The cleaning device 6 includes a fur brush 101, a cleaning blade 62, and the like. The cleaning blade 62 is in contact with the photoconductor 3 in the counter direction with respect to the surface movement direction of the photoconductor 3. The cleaning blade 62 is the cleaning blade of the present invention.
The lubricant application device 10 includes a solid lubricant 103, a lubricant pressure spring 103 a, and the like, and uses a fur brush 101 as an application brush for applying the solid lubricant 103 onto the photoreceptor 3. The solid lubricant 103 is held by the bracket 103b and is pressed toward the fur brush 101 by a lubricant pressurizing spring 103a. Then, the solid lubricant 103 is scraped by the fur brush 101 that rotates in the rotational direction with respect to the rotation direction of the photoconductor 3, and the lubricant is applied onto the photoconductor 3. By applying lubricant to the photoreceptor, the friction coefficient on the surface of the photoreceptor 3 is maintained at 0.2 or less during non-image formation.

  In FIG. 2, a non-contact proximity arrangement method in which the charging roller 4 is brought close to the photosensitive member 3 is adopted. However, as a charging device, a corotron, a scorotron, a solid state charger (solid state charger), and the like can be used. A known configuration can be used. Of these charging methods, a contact charging method or a non-contact proximity arrangement method is particularly desirable, and has advantages such as high charging efficiency and a small amount of ozone generation, and miniaturization of the apparatus.

The light source of the laser light L of the optical writing unit 40 and the light source such as a charge removal lamp are not particularly limited, and all luminescent materials can be used. Specific examples include a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), and electroluminescence (EL).
In addition, various types of filters such as a sharp cut filter, a band pass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can be used to irradiate only light in a desired wavelength range.
Among these light sources, light emitting diodes and semiconductor lasers are used favorably because they have high irradiation energy and long wavelength light of 600 to 800 [nm].

  In addition to the intermediate transfer belt 14, the transfer unit 60, which is a transfer means, includes a belt cleaning unit 162, a first bracket 63, a second bracket 64, and the like. Further, four primary transfer rollers 7Y, 7C, 7M, and 7K, a secondary transfer backup roller 66, a driving roller 67, an auxiliary roller 68, a tension roller 69, and the like are also provided. The intermediate transfer belt 14 is endlessly moved counterclockwise in the figure by the rotational driving of the driving roller 67 while being stretched around these eight roller members. The four primary transfer rollers 7Y, 7C, 7M, and 7K sandwich the intermediate transfer belt 14 thus moved endlessly with the photoreceptors 3Y, 3C, 3M, and 3K to form primary transfer nips, respectively. Yes. Then, a transfer bias having a polarity opposite to that of the toner (for example, plus) is applied to the back surface (loop inner peripheral surface) of the intermediate transfer belt 14. The intermediate transfer belt 14 sequentially passes through the primary transfer nips for Y, C, M, and K along with its endless movement, and on the front surface thereof, the intermediate transfer belt 14 is on the photoreceptors 3Y, 3C, 3M, and 3K. Y, C, M, and K toner images are superimposed and primarily transferred. As a result, a four-color superimposed toner image (hereinafter referred to as a four-color toner image) is formed on the intermediate transfer belt 14.

  The secondary transfer backup roller 66 sandwiches the intermediate transfer belt 14 with the secondary transfer roller 70 disposed outside the loop of the intermediate transfer belt 14 to form a secondary transfer nip. The registration roller pair 55 described above feeds the transfer paper P sandwiched between the rollers toward the secondary transfer nip at a timing at which the transfer paper P can be 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 affected by the secondary transfer electric field formed between the secondary transfer roller 70 to which the secondary transfer bias is applied and the secondary transfer backup roller 66, and the influence of the nip pressure. The secondary transfer is performed on the transfer paper P in the secondary transfer nip. Then, combined with the white color of the transfer paper P, a full color toner image is obtained.

  Transfer residual toner that has not been transferred to the transfer paper P adheres to the intermediate transfer belt 14 after passing through the secondary transfer nip. This is cleaned by the belt cleaning unit 162. The belt cleaning unit 162 has a belt cleaning blade 162a in contact with the front surface of the intermediate transfer belt 14, thereby scraping off and removing the transfer residual toner on the intermediate transfer belt 14.

  The first bracket 63 of the transfer unit 60 swings at a predetermined rotation angle about the rotation axis of the auxiliary roller 68 as the solenoid is turned on / off. When forming a monochrome image, the printer 500 rotates the first bracket 63 a little counterclockwise in the drawing by driving the solenoid described above. This rotation causes the primary transfer rollers 7Y, 7C, and 7M to revolve counterclockwise in the drawing around the rotation axis of the auxiliary roller 68, thereby separating the intermediate transfer belt 14 from the photoreceptors 3Y, 3C, and 3M. Of the four image forming units 1Y, 1C, 1M, and 1K, only the K image forming unit 1K is driven to form a monochrome image. Thereby, it is possible to prevent the Y, C, and M image forming units 1 from being driven unnecessarily during monochrome image formation, and to avoid the consumption of each member constituting the image forming unit 1.

  A fixing unit 80 is disposed above the secondary transfer nip in the drawing. The fixing unit 80 includes a pressure heating roller 81 that contains a heat source such as a halogen lamp, and a fixing belt unit 82. The fixing belt unit 82 includes a fixing belt 84 that is a fixing member, a heating roller 83 including a heat source such as a halogen lamp, a tension roller 85, a driving roller 86, a temperature sensor, and the like. Then, the endless fixing belt 84 is endlessly moved in the counterclockwise direction in the drawing while being stretched by the heating roller 83, the tension roller 85, and the driving roller 86. In the process of endless movement, the fixing belt 84 is heated from the back side by the heating roller 83. A pressure heating roller 81 that is driven to rotate in the clockwise direction in the drawing is in contact with the surface of the fixing belt 84 that is heated in this manner, around the heating roller 83. Thus, a fixing nip where the pressure heating roller 81 and the fixing belt 84 abut is formed.

  A temperature sensor is disposed outside the loop of the fixing belt 84 so as to face the front surface of the fixing belt 84 with a predetermined gap, and the surface temperature of the fixing belt 84 immediately before entering the fixing nip. Is detected. This detection result is sent to the fixing power supply circuit. The fixing power supply circuit performs on / off control of power supply to the heat generation source included in the heating roller 83 and the heat generation source included in the pressure heating roller 81 based on the detection result by the temperature sensor.

The transfer paper P that has passed through the secondary transfer nip is separated from the intermediate transfer belt 14 and then sent into the fixing unit 80. The full color toner image is fixed on the transfer paper P by being heated and pressed by the fixing belt 84 while being conveyed from the lower side to the upper side in the figure while being sandwiched by the fixing nip in the fixing unit 80. The
The transfer paper P subjected to the fixing process in this manner is discharged between the discharge roller pair 87 and then discharged outside the apparatus. A stack unit 88 is formed on the upper surface of the housing of the printer 500 main body, and the transfer paper P discharged to the outside by the discharge roller pair 87 is sequentially stacked on the stack unit 88.

  Above the transfer unit 60, four toner cartridges 100Y, 100C, 100M, and 100K that store Y, C, M, and K toners are disposed. The Y, C, M, and K toners in these toner cartridges are appropriately supplied to the developing devices 5Y, 5C, 5M, and 5K of the image forming units 1Y, 1C, 1M, and 1K. The toner cartridges 100Y, 100C, 100M, and 100K are detachable from the printer main body independently of the image forming units 1Y, 1C, 1M, and 1K.

Next, an image forming operation in the printer 500 will be described.
When a print execution signal is received from the operation unit or the like, a predetermined voltage or current is sequentially applied to the charging roller 4 and the developing roller 51 at a predetermined timing. Similarly, a predetermined voltage or current is sequentially applied to a light source such as the optical writing unit 40 and the static elimination lamp at a predetermined timing. In synchronism with this, the photosensitive member 3 is rotationally driven in the direction of the arrow in the figure by a photosensitive member driving motor as driving means.

When the photoconductor 3 rotates in the direction of the arrow in the figure, the surface of the photoconductor 3 is first uniformly charged to a predetermined potential by the charging roller 4. Then, the laser beam L corresponding to the image information is irradiated onto the photoconductor 3 from the optical writing unit 40, and the portion irradiated with the laser light L on the surface of the photoconductor 3 is neutralized to form an electrostatic latent image. .
The surface of the photoreceptor 3 on which the electrostatic latent image is formed is rubbed by a developer magnetic brush formed on the developing roller 51 at a portion facing the developing device 5. At this time, the negatively charged toner on the developing roller 51 moves to the electrostatic latent image side by a predetermined developing bias applied to the developing roller 51, and is formed into a toner image (development). A similar image forming process is executed in each image forming unit 1, and toner images of respective colors are formed on the surfaces of the respective photoreceptors 3Y, 3C, 3M, and 3K of the image forming units 1Y, 1C, 1M, and 1K.
As described above, in the printer 500, the electrostatic latent image formed on the photoconductor 3 is reversely developed by the developing device 5 with the negatively charged toner. Here, an example using a non-contact charging roller system of N / P (negative positive: toner adheres to a low potential) has been described, but the present invention is not limited to this.

The toner images of the respective colors formed on the surfaces of the photoreceptors 3Y, 3C, 3M, and 3K are sequentially primary-transferred so as to overlap on the surface of the intermediate transfer belt 14. As a result, a four-color toner image is formed on the intermediate transfer belt 14.
The four-color toner image formed on the intermediate transfer belt 14 is fed from the first paper feed cassette 151 or the second paper feed cassette 152, passed between the rollers of the registration roller pair 55, and fed to the secondary transfer nip. The transfer paper P is transferred. At this time, the transfer paper P is temporarily stopped while being sandwiched between the registration roller pair 55, and is supplied to the secondary transfer nip in synchronization with the leading edge of the image on the intermediate transfer belt 14. The transfer paper P onto which the toner image has been transferred is separated from the intermediate transfer belt 14 and conveyed to the fixing unit 80. Then, the transfer paper P on which the toner image is transferred passes through the fixing unit 80, whereby the toner image is fixed on the transfer paper P by the action of heat and pressure, and the transfer paper P on which the toner image is fixed is the printer 500. It is discharged out of the apparatus and stacked on the stack unit 88.

On the other hand, the transfer residual toner on the surface of the intermediate transfer belt 14 that has transferred the toner image onto the transfer paper P at the secondary transfer nip is removed by the belt cleaning unit 162.
Further, the surface of the photoreceptor 3 on which the toner images of the respective colors are transferred to the intermediate transfer belt 14 at the primary transfer nip, the residual toner after the transfer is removed by the cleaning device 6, and the lubricant is applied by the lubricant applying device 10. Thereafter, the charge is removed by a charge removal lamp.

The image carrier and the cleaning blade of the present invention are integrally formed, and a process cartridge that is detachable from the main body of the image forming apparatus can be obtained.
As shown in FIG. 2, the image forming unit 1 of the printer 500 includes a photosensitive member 3 and a charging roller 4, a developing device 5, a cleaning device 6, a lubricant applying device 10, and the like as process means. ing. The image forming unit 1 can be integrally attached to and detached from the main body of the printer 500 as a process cartridge. In the printer 500, the image forming unit 1 integrally replaces the photoconductor 3 as a process cartridge and the process means. However, the photoconductor 3, the charging roller 4, the developing device 5, the cleaning device 6, and the lubricant applying device 10 may be replaced with new ones.

Next, a preferable toner when the cleaning blade of the present invention is applied to the printer 500 will be described.
As the toner used in the printer 500, it is preferable to use a polymerized toner produced by a suspension polymerization method, an emulsion polymerization method, or a dispersion polymerization method, which is easy to increase the circularity and the particle size for improving the image quality. In particular, it is preferable to use a polymerized toner having a circularity of 0.97 or more and a volume average particle size of 5.5 [μm] or less because a higher resolution image can be formed.

  The “circularity” here is an average circularity measured by a flow type particle image analyzer FPIA-2000 (manufactured by Toa Medical Electronics Co., Ltd.). Specifically, 0.1 to 0.5 [ml] of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 [ml] of water from which solid impurities have been removed in advance, and measurement is further performed. Add about 0.1 to 0.5 [g] of sample (toner). Thereafter, the suspension in which the toner is dispersed is dispersed by an ultrasonic disperser for about 1 to 3 minutes, and the dispersion concentration is set to 3000 to 10,000 [pieces / μL] and set in the above-described analyzer. Then, the shape and distribution of the toner particles are measured. Based on the measurement result, the perimeter (outer circumference) of the actual toner particle projection shape shown in FIG. 3A is C1, the projection area is S, and the area shown in FIG. C2 / C1 when the peripheral length (peripheral length) of C2 was C2 was determined, and the average value was defined as the circularity.

  The volume average particle diameter can be determined by a Coulter counter method. Specifically, the toner number distribution and volume distribution data measured by the Coulter Multisizer 2e type (manufactured by Coulter) are sent to a personal computer for analysis via an interface (manufactured by Nikka Kikai). More specifically, a 1% NaCl aqueous solution using first grade sodium chloride is prepared as an electrolytic solution. Then, 0.1 to 5 [ml] of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to the electrolytic aqueous solution 100 to 150 [ml]. Further, 2 to 20 [mg] of the toner of the test sample is added thereto, and the dispersion treatment is performed for about 1 to 3 [minutes] with an ultrasonic disperser. Then, 100 to 200 [ml] of the electrolytic solution is put into another beaker, and the solution after the dispersion treatment is added therein to a predetermined concentration, and applied to the Coulter Multisizer 2e type. The aperture is 100 [μm], and the particle size of 50,000 toner particles is measured. As a channel, it is less than 2.00-2.52 [micrometer]; 2.52-less than 3.17 [micrometer]; 3.17-less than 4.00 [micrometer]; 4.00-5.04 [micrometer] Less than 5.04 to 6.35 [μm]; 6.35 to less than 8.00 [μm]; 8.00 to less than 10.08 [μm]; 10.08 to less than 12.70 [μm]; 12.70 to less than 16.00 [μm]; 16.00 to less than 20.20 [μm]; 20.20 to less than 25.40 [μm]; 25.40 to less than 32.00 [μm]; Using 13 channels of 00 to less than 40.30 [μm], toner particles with a particle size of 2.00 [μm] or more and 32.0 [μm] or less are targeted. Then, the volume average particle diameter is calculated based on the relational expression “volume average particle diameter = ΣDfV / ΣfV”. However, “D” is the representative diameter in each channel, “V” is the equivalent volume in the representative diameter of each channel, and “f” is the number of particles in each channel.

  EXAMPLES Hereinafter, although an Example and a comparative example are shown and demonstrated concretely, this invention is not limited at all by these Examples.

[Elastic blade]
For the elastic blade, six types of urethane rubber having the following physical properties at 25 [° C.] were used.
Urethane rubber 1: hardness 72 degrees, rebound resilience 31 [%] (manufactured by Toyo Tire & Rubber Co., Ltd.)
Urethane rubber 2: hardness 69 degrees, rebound resilience 50 [%] (manufactured by Toyo Tire & Rubber Co., Ltd.)
Urethane rubber 3: Hardness 68 degrees, rebound resilience 30 [%] (manufactured by Toyo Tire & Rubber Co., Ltd.)
Urethane rubber 4: Hardness 75 degrees, rebound resilience 45 [%] (manufactured by Toyo Tire & Rubber Co., Ltd.)
Urethane rubber 5: 2-layer construction, blade contact surface side: hardness 80 degrees, opposite surface side: hardness 75 degrees
Rebound resilience 25 [%] (Toyo Tire & Rubber Co., Ltd.)
Urethane rubber 6: 2-layer construction, blade contact surface side: hardness 66 degrees, opposite surface side: hardness 75 degrees
Rebound resilience 30 [%] (Bando Chemical Co., Ltd.)

  The hardness of urethane rubber was measured according to JIS K6253 using a micro rubber hardness meter MD-1 manufactured by Kobunshi Keiki Co., Ltd. The two-layer blade was measured from each side. The resilience of urethane rubber is No. manufactured by Toyo Seiki Seisakusho. The measurement was performed according to JIS K6255 using a 221 regilynester. The sample was a stack of approximately 2 [mm] sheets so that the thickness was 4 [mm] or more.

[Impregnation and surface layer materials]
The following hardening materials 1-8 were used for the impregnation layer forming part and the surface layer forming part.
The unit of the blending amount of the constituent material is “part by mass”.
<Curing material 1>
Monomer 1: PETIA 8.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 2: ODA-N 2.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 3: OPTOOL DAC-HP 0.1 parts manufactured by Daikin Co., Ltd. Polymerization initiator: manufactured by Ciba Specialty Chemicals Irgacure 184 0.5 part Solvent: Cyclohexanone 89.4 parts

<Curing material 2>
Monomer 1: PETIA 7.0 part manufactured by Daicel Cytec Co., Ltd. Monomer 2: HDDA 3.0 part manufactured by Daicel Cytec Co., Ltd. Polymerization initiator: Irgacure 184 0.5 part manufactured by Ciba Specialty Chemicals Solvent: Cyclohexanone 89.5 parts

<Curing material 3>
Monomer 1: PETIA 10.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 2: OPTOOL DAC-HP 0.1 parts manufactured by Daikin Co., Ltd. Polymerization initiator: Irgacure 184 0.5 parts manufactured by Ciba Specialty Chemicals Solvent: Cyclohexanone 89.4 parts

<Curing material 4>
Monomer 1: PETIA 8.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 2: IBOA 2.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 3: OPTOOL DAC-HP 0.1 parts manufactured by Daikin Co., Ltd. Polymerization initiator: Irgacure 184 manufactured by Ciba Specialty Chemicals 0.5 part Solvent: 89.4 parts of cyclohexanone

<Curing material 5>
Monomer 1: PETIA 7.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 2: EBECRYL 11 3.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 3: OPTOOL DAC-HP 0.1 parts manufactured by Daikin Co., Ltd. Polymerization initiator: Irgacure 184 manufactured by Ciba Specialty Chemicals 0.5 part Solvent: 89.4 parts of cyclohexanone

<Curing material 6>
Monomer 1: DPHA 10.0 parts manufactured by Daicel-Cytec Co., Ltd. Polymerization initiator: Irgacure 184 1.0 parts manufactured by Ciba Specialty Chemicals Solvent: Cyclohexanone 89.0 parts

<Curing material 7>
Monomer 1: DPCA-120 manufactured by Nippon Kayaku Co., Ltd. 8.0 parts Monomer 2: IBOA 2.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 3: RS-75 0.1 parts manufactured by DIC Co., Ltd. Polymerization initiator: manufactured by Ciba Specialty Chemicals Irgacure 184 0.5 part Solvent: Cyclohexanone 89.4 parts

<Curing material 8>
Monomer 1: PETIA 5.0 parts manufactured by Daicel Cytec Co., Ltd. Monomer 2: UN2700 5.0 parts manufactured by Negami Kogyo Co., Ltd. Monomer 3: RS-75 0.1 parts manufactured by DIC Co., Ltd. Polymerization initiator: Irgacure 184 0 manufactured by Ciba Specialty Chemicals .5 parts Solvent: 89.4 parts cyclohexanone

  Among the above monomers, OPTOOL DAC-HP manufactured by Daikin and RS-75 manufactured by DIC are fluorinated acrylic monomers, have an perfluoropolyether skeleton, and are acrylates having two or more functional groups. That is, the curable materials 1, 3, 4, 5, 7, and 8 are ultraviolet curable resin monomer mixtures containing a fluorinated acrylic monomer.

Table 1 shows the acrylic monomers used for the curable materials 1 to 8, their main skeleton, the number of functional groups, and the functional group equivalent molecular weight.

As shown in Table 1 above, Daicel Cytec Co., Ltd .: PETIA, DPHA, and Nippon Kayaku Co., Ltd .: DPCA-120 have a functional group equivalent molecular weight of 350 or less and a functional group number of 3 to 6 pentaerythritol triacrylate. As an acrylic monomer.
Moreover, Daicel Cytec make: ODA-N, HDDA, IBOA, EBECRYL11 and Negami Kogyo make: UN2700 are the acrylic monomer of functional group equivalent molecular weight 100-1000 and functional group 1-2.
Therefore, the curable materials 1, 2, 4, 5, 7, and 8 are curable materials obtained by mixing the two types of acrylic monomers.

Examples 1-9, Comparative Examples 1-6
Using the urethane rubber, impregnation material, and surface layer material as shown in each column of Examples 1 to 9 and Comparative Examples 1 to 6 in Table 2, as shown in each column, surface layer formation of the tip surface and the contact surface Each cleaning blade was prepared by changing the formation state of each part and the impregnated layer forming part (formation phase of each layer on the tip surface and contact surface, impregnation depth, surface layer thickness, formation width of each layer).
A verification experiment was performed for each of these cleaning blades as follows. The results are shown in Table 2.

<Production of image forming apparatus for which verification experiment was performed>
Using each of the above urethane rubbers, each strip-shaped elastic blade having a thickness of 1.8 [mm] was produced. Next, in order to form a surface layer, masking was performed so as to cover a portion where the surface layer was not formed on the blade tip surface and the blade contact surface. For masking, apply a pattern with masking tape (3M PTFE tape 5490) so that the boundary between the surface layer formation part and the impregnation layer formation part is perpendicular to the blade ridgeline on the blade contact surface and blade tip surface. It was. Subsequently, a surface layer was formed on the blade contact surface and the blade tip surface masked by using the curable material shown in Table 2 by a spray coating method in order to provide the surface layer. The surface layer is formed by spray coating, and the thickness of the surface layer on the blade contact surface and the blade tip surface is as shown in Table 2 at a spray gun moving speed of 10 [mm / s]. In this way, overcoating was performed, and finger touch drying was performed for 3 minutes. Thereafter, ultraviolet exposure (2000 [mJ / cm ² ] × 3 passes) was performed. The formation width [d] in the ridge line vertical direction of the surface layer forming portion on the blade contact surface is as shown in Table 2, and the surface layer forming portion was formed over the entire length in the ridge line vertical direction on the blade tip surface.
Further, the formation of the impregnation layer uses the surface layer already formed as a mask, the width in the vertical direction of the ridge line is the same as that of the surface layer formation portion, and the impregnation depth described in Table 2 using the cured material described in Table 2. After being soaked and appropriately impregnating, it was air-dried for 3 minutes. Thereafter, ultraviolet exposure (2000 [mJ / cm ² ] × 3 passes) was performed in the same manner.
When providing the second surface layer, before performing the ultraviolet exposure of the impregnated layer, using the same curing material as the surface layer, in the same region as the combined region of the surface layer forming portion and the impregnated layer forming portion. Similarly, a second surface layer having a thickness shown in Table 2 was formed by spray coating, and ultraviolet exposure (2000 [mJ / cm ² ] × 3 passes) was performed again.
In Examples 1 to 9, the Martens hardness of the surface layer forming portion and the impregnation layer forming portion was higher than the Martens hardness of the elastic blade.

  The thickness of the surface layer and the second surface layer was measured with a cross section of the elastic blade using a microscope VHX-100 manufactured by Keyence Corporation. The measurement sample was a cross-section cut using a trimming razor for SEM sample preparation manufactured by Nisshin EM.

The impregnation material is detected in the vicinity of the tip ridge line portion of the elastic blade by the impregnation treatment, and this is formed with a so-called concentration gradient in which the detection intensity decreases from the surface side where the impregnation treatment is performed. . Therefore, the impregnation depth is a distance from the surface side where the impregnated material is hardly detected.
Specifically, the measurement of the impregnation depth (impregnation treatment region) was performed as follows.
A cross-sectional slice of the edge portion of the target sample was prepared with a cryomicrotome (EM / FCS, manufactured by Leica) and measured with a transmission microscope FT-IR (Continuum infrared microscope, manufactured by Thermo Electron). As shown in FIG. 4E, changes in the cross section were measured as appropriate with reference to the blade tip surface 62a and the blade contact surface 62b. The impregnation depth of the acrylic compound was measured using as an index the value obtained by dividing the peak area near 1710 cm ^{−1 by} the peak area of 1415 cm ⁻¹ with the value of the non-impregnated part.

  The elastic blade on which the surface layer and the impregnation layer were formed was fixed with an adhesive to a sheet metal holder that can be mounted on the color composite machine imagio MP C5000 manufactured by Ricoh Co., to obtain a prototype cleaning blade. This was attached to the above imagio MP C5000 (same configuration as in FIG. 1), and each image forming apparatus was produced. The cleaning blade was attached with the line pressure and the cleaning angle set according to the tip biting amount and attachment angle of the standard setting of the corresponding model.

<Toner used for verification experiment>
In the verification experiment, a toner prepared by a polymerization method was used. The physical properties of the toner are as follows.
Toner base: circularity 0.98, average particle size 4.9 [μm]
External additive: Small particle size silica: 1.5 parts (H1303 manufactured by Clariant Japan)
Small particle size titanium oxide: 0.5 part (MT-150AI manufactured by Teika)
Large particle size silica: 1.0 part (UFP-35HH manufactured by Denki Kagaku)

In the verification experiment, an experiment environment: low temperature environment 10 [° C.] / 15 [% RH], paper feeding condition: image area ratio 5% chart was set to 3 prints / job, and 10,000 sheets (A4 landscape) paper feeding test was performed. .
The following items were evaluated.
[Evaluation item]
-Presence or absence of defective cleaning after 10,000 sheets: The output image was visually observed.
-Adherence of foreign matter on photoreceptor surface after 10,000 sheets: Foreign matter adhesion (filming) on the photoreceptor was observed using a microscope VHX-100 manufactured by Keyence Corporation.
Abnormal noise: When the cleaning blade wears over time, the driving torque of the photosensitive member increases and abnormal noise is generated. As suppression of drive torque rise and evaluation of wear resistance, the presence or absence of abnormal sounds of chatter (low frequency of several hundred Hz) and squeal (high frequency of several kHz) was judged by hearing.

L laser beam P transfer paper 1 image forming unit 1Y image forming unit 1C image forming unit 1M image forming unit 1K image forming unit 2 frame 3 photoconductor 3Y photoconductor 3C photoconductor 3M photoconductor 3K photoconductor 4 charging roller 5 developing device 5Y developing device 5C developing device 5M developing device 5K developing device 6 cleaning device 7 primary transfer roller 7Y primary transfer roller 7C primary transfer roller 7M primary transfer roller 7K primary transfer roller 8 charging roller cleaner 10 lubricant application device 14 intermediate transfer belt 40 light Writing unit 41 Polygon mirror 51 Developing roller 52 Supply screw 53 Stirring screw 54 Doctor 55 Registration roller pair 60 Transfer unit 62 Cleaning blade 62a Blade tip surface 62b Blade contact surface 62c Tip ridge line portion 62d Impregnation layer forming portion 63 First Bracket 64 Second Bracket 66 Secondary Transfer Backup Roller 67 Drive Roller 68 Auxiliary Roller 69 Tension Roller 70 Secondary Transfer Roller 80 Fixing Unit 81 Pressure Heating Roller 82 Fixing Belt Unit 83 Heating Roller 84 Fixing Belt 85 Tension Roller 86 Driving Roller 87 Discharge roller pair 88 Stack unit 100Y Toner cartridge 100C Toner cartridge 100M Toner cartridge 100K Toner cartridge 101 Fur brush 103 Solid lubricant 103a Lubricant pressure spring 103b Bracket 123 Image carrier 151 First paper feed cassette 151a First feed Paper roller 152 Second paper feed cassette 152a Second paper feed roller 153 Paper feed path 154 Conveying roller pair 162 Belt cleaning unit 162a Belt cleaning blade 500 Printer 621 Holder 622 Elastic blade 623 Surface layer

JP 2013-218277 A Japanese Patent No. 5858645 Japanese Patent No. 4722680

Claims (10)

In a cleaning blade that is composed of a strip-shaped elastic blade, abutting a tip ridge line portion of the elastic blade with a member to be cleaned, and removing powder from the surface of the member to be cleaned,
From the ultraviolet curable resin over a width of at least 2 [mm] in the blade ridge line vertical direction from the tip ridge line portion of the blade contact surface facing the member to be cleaned and the blade tip surface parallel to the thickness direction of the elastic blade. A cleaning blade in which surface layer forming portions and impregnation layer forming portions having higher hardness than the elastic blade are alternately present in the blade ridge direction.   The cleaning blade according to claim 1, wherein in the cleaning blade, the formation positions of the surface layer forming portion and the impregnation layer forming portion on the blade contact surface and the blade tip surface are in phase with respect to the blade ridge line direction.   2. The cleaning blade according to claim 1, wherein in the cleaning blade, the formation positions of the surface layer forming portion and the impregnation layer forming portion on the blade contact surface and the blade tip surface are in opposite phases with respect to the blade ridge line direction.   In the cleaning blade, the surface layer forming portion and the impregnation layer forming portion alternately exist with a constant width, and the sum of the width of the surface layer forming portion and the width of the impregnation layer forming portion in the blade ridge line direction on the blade contact surface is 3 -5 [mm], the width of the surface layer forming part is 2 [mm] or more, the width of the surface layer forming part is larger than the width of the impregnating layer forming part, and the surface layer forming part and the impregnating layer in the direction perpendicular to the blade ridge line The cleaning blade according to claim 1, wherein the width of the forming portion is 2 to 5 [mm].   5. The cleaning blade according to claim 1, wherein a boundary between the surface layer forming portion and the impregnation layer forming portion on the blade contact surface is perpendicular to the blade ridge line.   In the cleaning blade, the impregnation depth from the blade tip surface of the impregnation layer forming portion on the blade tip surface is 100 to 200 [μm], and the impregnation depth from the blade contact surface of the impregnation layer forming portion on the blade contact surface is The cleaning blade according to claim 1, which is 50 to 150 [μm].   The cleaning blade according to any one of claims 1 to 6, wherein in the cleaning blade, the thickness of the surface layer of the surface layer forming portion on the blade tip surface and the blade contact surface is 1.0 to 2.5 [μm]. .   The cleaning blade further includes a second surface layer covering the surface layer forming portion and the impregnation layer forming portion on the blade tip surface and the blade contact surface, and the thickness of the second surface layer on the blade tip surface and the blade contact surface. The cleaning blade according to claim 7, having a thickness of 0.5 to 1.0 [μm].   An image carrier, a charging unit for charging the surface of the image carrier, a latent image forming unit for forming an electrostatic latent image on the charged surface of the image carrier, and the electrostatic image formed on the surface of the image carrier. Developing means for developing the latent image into a toner image; Transfer means for transferring the toner image on the surface of the image carrier to the transfer member; and Transfer attached to the surface of the image carrier in contact with the surface of the image carrier 9. An image forming apparatus comprising a cleaning unit having a cleaning blade for cleaning residual toner, wherein the image forming apparatus uses the cleaning blade according to claim 1 as the cleaning blade.   9. A process cartridge that is detachably attached to an image forming apparatus main body, wherein the image carrier and the cleaning blade according to claim 1 are integrally formed.

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