JP6962058B2 - Cleaning blades, cleaning blade manufacturing methods, process cartridges, image forming devices and image forming methods - Google Patents

Description

The present invention relates to a cleaning blade, a method for manufacturing a cleaning blade, a process cartridge, an image forming apparatus, and an image forming method.

Conventionally, in an electrophotographic image forming apparatus, an image carrier as a member to be cleaned (hereinafter, may be referred to as a "photoreceptor", an "electrophotographic photosensitive member", or an "electrostatic latent image carrier") is used. It is known that unnecessary deposits such as transfer residual toner adhering to the surface after the toner image is transferred to the transfer paper or the intermediate transfer body are removed by a cleaning means.

As a cleaning member of the cleaning means, a strip-shaped cleaning blade is generally well known because it can be easily configured and has excellent cleaning performance. In this method, the base end of the cleaning blade is supported by a support member, the contact portion (tip ridge line portion) is pressed against the peripheral surface of the image carrier, and the toner remaining on the image carrier is blocked and scraped off. ..

Further, in order to meet the demand for higher image quality in recent years, an image forming apparatus using a toner having a small particle size and a nearly spherical shape (hereinafter, may be referred to as "polymerized toner") formed by a polymerization method or the like is known. ing. The polymerized toner has features such as higher transfer efficiency than the conventional pulverized toner, and can meet the above-mentioned requirements.

However, even if the polymerized toner is attempted to be removed from the surface of the image carrier using a cleaning blade, it is difficult to sufficiently remove the polymerized toner, and there is a problem that cleaning failure occurs. This is because the polymerized toner having a small particle size and excellent sphericity slips through a slight gap formed between the cleaning blade and the image carrier.

In order to suppress slip-through, it is necessary to increase the contact pressure between the image carrier and the cleaning blade to increase the cleaning ability, but if the contact pressure is increased, turning occurs as shown in FIG. 9 (A). Further, when it is used in the turned-up state, local wear occurs as shown in FIG. 9 (B), and finally the tip ridge line portion is missing as shown in FIG. 9 (C).

In order to solve such a problem, for example, Patent Document 1 proposes a method in which a layer made of a resin having a film hardness of pencil hardness B to 6H is provided at an abutting portion of an elastic member made of a polyurethane elastomer. There is.
Patent Document 2 proposes a cleaning blade in which a rubber elastic member is impregnated with an ultraviolet curable composition containing silicone to swell, and then subjected to ultraviolet irradiation treatment to cure the ultraviolet curable composition. ing.
In Patent Document 3, at least one selected from an isocyanate compound, a fluorine compound, and a silicone compound is impregnated in a portion including a contact portion of the elastic member, and the surface of the elastic member including the contact portion is more than an elastic member. Cleaning blades provided with a hard surface layer have been proposed.
Patent Document 4 proposes a cleaning blade having a coating layer containing lubricating particles and a binder resin.
In Patent Document 5, the tip ridge portion of the cleaning blade is composed of a base material made of an elastic body of the elastic blade, a mixed layer of the base material and acrylic or / and methacrylic resin, and an acrylic or / and methacrylic resin layer. A laminated structure of the surface layer has been proposed. Further, Patent Document 5 discloses that the thickness of the surface layer is 0.5 to 1.0 μm.

However, it is difficult to completely suppress the turning of the tip ridge line portion with the conventional cleaning blade provided with a cured layer (surface layer or the like) and the cleaning blade provided with an impregnated portion. Further, in recent years, there is an increasing need for high speed in an image forming apparatus based on an electrophotographic method, and when the image forming speed is increased, the tip ridge line portion is easily turned over and the tip ridge line portion is missing.

Under such severe conditions, the tip ridgeline portion may be chipped due to turning over, resulting in poor cleaning or abnormal noise. Further, such a chipping of the tip ridge line portion may occur locally in the longitudinal direction of the cleaning blade, and when the local missing portion occurs, toner or the like is applied to the surface of the image carrier corresponding to the missing portion. It becomes easy to stick, and an abnormal image such as a white-out image may occur.

Further, even with a cleaning blade in which a hardened layer is formed on a portion including a contact portion, it is difficult to increase the layer thickness of the contact portion when it is formed by a method such as spray coating, and the layer thickness of the contact portion is thin. The hardened layer wears out early. As a result, the base material of the elastic member comes into contact with the image carrier, which causes a problem that the torque with the image carrier increases. When the torque increases, a load is applied to the rotation of the image carrier, and for example, color shift in the tandem method occurs.

On the other hand, Patent Document 6 proposes a cleaning device provided with a predetermined lubricant-applied brush roller, a first flicker member, and a second flicker member, and hits an edge that abuts on an image carrier. An obtuse angle blade having a tangent angle of 90 ° <θ ≦ 150 ° is disclosed. However, Patent Document 6 does not provide a cured layer, and there are problems in curling, abrasion, and cleanability when used for a long period of time.

The present invention suppresses the loss of the tip ridge line portion due to turning of the tip ridge line portion, maintains good cleanability for a long period of time, suppresses the adhesion of toner or the like to the member to be cleaned, and suppresses the generation of abnormal images. It is an object of the present invention to provide a cleaning blade which can be used.

In order to solve the above problems, the cleaning blade of the present invention includes an elastic member that comes into contact with the surface of the member to be cleaned and removes deposits adhering to the surface of the member to be cleaned. It has a material and a cured product layer made of a cured product of a curable composition, and the cured product layer includes the contact portion on at least a part of a surface including a contact portion that contacts the member to be cleaned. Formed by
The thickness of the cured product layer at the contact portion is 10 μm or more and 100 μm or less, and the surface of the elastic member facing the member to be cleaned on the upstream side of the contact portion and the downstream side of the contact portion. in the angle between the surface of the elastic member facing the object to be cleaned member, Ri <br/> Oh at 110 ° or 145 ° or less, Martens hardness of the cured product layer has a 3N / mm ² or more, the Martens hardness of the base material, characterized in der Rukoto 2N / mm ² or less.

According to the present invention, it is possible to suppress the loss of the tip ridge line portion due to the tip ridge line portion being turned over, maintain good cleanability for a long period of time, suppress the adhesion of toner or the like to the member to be cleaned, and generate an abnormal image. Can be suppressed.

FIG. 5 is an enlarged cross-sectional view showing an example of a state in which the cleaning blade according to the present invention is in contact with the surface of the image carrier. It is a perspective view which shows an example of the cleaning blade which concerns on this invention. It is sectional drawing explaining one example (A) and other examples (B), (C) of the cleaning blade which concerns on this invention. It is a schematic block diagram which shows an example of the image forming apparatus which concerns on this invention. It is a schematic block diagram which shows an example of the image formation unit provided in the image forming apparatus which concerns on this invention. It is explanatory drawing (A) and (B) for demonstrating the method of measuring the circularity of toner. It is sectional drawing of the cleaning blade in the comparative example. It is a figure (A) and (B) for demonstrating an example of the method of measuring the layer thickness of a cured product layer. A diagram showing a state in which the tip ridge of a conventional cleaning blade is rolled up, a diagram (B) explaining local wear of the tip surface of the cleaning blade, and a diagram showing a state in which the tip ridge of the cleaning blade is missing. (C).

Hereinafter, the cleaning blade, the method for manufacturing the cleaning blade, the process cartridge, the image forming apparatus, and the image forming method according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments shown below, and can be modified within the range conceivable by those skilled in the art, such as other embodiments, additions, modifications, and deletions. However, as long as the action and effect of the present invention are exhibited, it is included in the scope of the present invention.

(Cleaning blade)
Conventionally, when a polymerized toner having a small particle size and excellent sphericity is used, there is a problem that a slight gap formed between the cleaning blade and the image carrier is slipped through. In order to suppress the slip-through, it is necessary to increase the contact pressure between the image carrier and the cleaning blade to enhance the cleaning ability. However, when the contact pressure of the cleaning blade is increased, as shown in FIG. 9A, the frictional force between the image carrier 123 and the cleaning blade 62 increases, and the cleaning blade 62 moves in the moving direction of the image carrier 123. When pulled, the tip ridge line portion 62c of the cleaning blade 62 is turned over. When the turned-up cleaning blade 62 is restored to its original state against the turned-up, an abnormal noise may be generated.

Further, when cleaning is continued with the tip ridge portion 62c of the cleaning blade 62 turned up, as shown in FIG. 9B, a portion several μm away from the tip ridge portion 62c of the blade tip surface 62a of the cleaning blade 62. Will cause local wear. If cleaning is continued in such a state, this local wear becomes large. Eventually, as shown in FIG. 9C, the tip ridge line portion 62c is missing. If the tip ridge line portion 62c is missing in this way, there is a problem that the toner cannot be cleaned normally and cleaning failure occurs. Note that 62b in FIGS. 9 (A) to 9 (C) is the lower surface of the cleaning blade.

On the other hand, the cleaning blade of the present invention includes an elastic member that comes into contact with the surface of the member to be cleaned and removes deposits adhering to the surface of the member to be cleaned, and the elastic member is hardened with a base material. It has a cured product layer made of a cured product of the sex composition, and the cured product layer is formed by including the contact portion on at least a part of a surface including the contact portion that contacts the member to be cleaned. The thickness of the cured product layer at the contact portion is 10 μm or more and 100 μm or less, and the surface of the elastic member facing the member to be cleaned on the upstream side of the contact portion and the downstream side of the contact portion. The angle formed by the surface of the elastic member facing the member to be cleaned is 110 ° or more and 145 ° or less.

An embodiment of the cleaning blade according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is an explanatory view of a state in which the cleaning blade 62 is in contact with the surface of the photoconductor 3, and FIG. 2 is a perspective view of the cleaning blade 62. In the cleaning blade 62 shown in the figure, a support member 621, an elastic member 624, a base material 622, and a cured product layer 623 are shown. Further, the blade tip surface 62a, the blade lower surface 62b, and the tip ridge line portion 62c (also referred to as a contact portion, an edge portion, etc.) are shown in the drawing. The figure is schematically shown, and the thickness, length, etc. are different from the actual scale.

In the present invention, the surface in the longitudinal direction of the base material constituting the elastic member, which faces the downstream side in the traveling direction (rotational direction in the present embodiment) of the member to be cleaned, is referred to as the lower surface of the base material, and the tip of the base material. The surface of the tip facing the upstream side in the rotation direction of the member to be cleaned including the ridge is called the tip surface of the base material.

Further, the surface of the elastic member in the longitudinal direction facing the downstream side in the rotation direction of the member to be cleaned is called the lower surface of the blade, and the tip of the tip facing the upstream side in the rotation direction of the member to be cleaned including the tip ridge of the elastic member. The surface is called the blade tip surface.
In FIG. 1, the surface 62b facing the downstream side B in the traveling direction of the member to be cleaned is the lower surface of the blade, and the surface 62a of the tip facing the upstream side A in the traveling direction of the member to be cleaned is the blade tip surface.
Further, the contact portion that comes into contact with the surface of the member to be cleaned of the elastic member includes the tip ridgeline portion of the elastic member. Further, when the tip ridge line portion is turned over or the linear pressure is high, a part of the blade tip surface can also be a contact portion.

In the present invention, the layer thickness of the cured product layer at the contact portion of the cleaning blade is 10 μm or more and 100 μm or less, and the angle D (also referred to as an internal angle D) formed by the blade tip surface 62a and the blade lower surface 62b is 110 ° ≦ D ≦. It is set to 145 °. As a result, it was found that the stress at the time of contact with the member to be cleaned is dispersed, and the local loss of the tip ridge line portion due to stress concentration can be suppressed. If the angle D formed is less than 110 °, the stress cannot be completely dispersed depending on the contact pressure, and the tip ridge line portion is turned over. Further, if the formed angle D exceeds 145 °, the deposits on the member to be cleaned are slipped through and adhere to the member to be cleaned, resulting in poor cleanability.
The range of the angle D to be formed is preferably 120 ° ≦ D ≦ 135 °, and in this case, local omission can be further reduced.

Further, when the layer thickness of the cured product layer at the contact portion exceeds 100 μm, it becomes difficult to maintain the flexibility of the elastic member of the base material, and it is resistant to vibration due to axial shake of the image carrier and minute waviness on the surface of the image carrier. It becomes difficult to deal with followability, and cleaning defects are likely to occur. If it is less than 10 μm, abnormal noise due to abnormal wear or the like will be generated.

Further, it was found that the thickness of the cured product layer at the contact portion is preferably 12 μm or more and 65 μm or less, and in this case, the improvement effect is remarkable. By setting the thickness to 12 μm or more and 65 μm or less, the initial contact portion is less likely to be turned over, and even if the wear progresses, the wear can be stopped in the cured product layer, and the exposure of the base material of the elastic member can be suppressed. Therefore, even after long-term use, turning, squeaking, and poor cleaning are less likely to occur.

Further, it was found that the maltens hardness of the cured product layer is preferably higher than the maltens hardness of the base material, and in this case, the improving effect is remarkable. Since the Martens hardness of the cured product layer is higher than that of the base material, it is possible to simultaneously establish the followability of the contact portion with the member to be cleaned by the flexible base material and the attitude controllability by the rigid cured product layer. .. Further, the Martens hardness of the cured product layer ^{is preferably 3 N / mm 2} or more, and the Martens hardness of the base material is preferably ² N / mm 2 or less, but the present invention is not limited to this.

Further, it was found that the cured product layer is preferably formed in a region of 1 to 7 mm from the contact portion, and in this case, the improving effect is remarkable. If the cured product layer is distributed wider than 7 mm, the flexibility of the elastic member may be hindered, the followability of the contact portion with the member to be cleaned may be deteriorated, and the adhered material may slip through. Therefore, it turned out to be disadvantageous for cleaning.

Here, FIG. 3 shows a schematic enlarged cross-sectional view of the base material and the cured product layer at the contact portion.
FIG. 3A shows an example in which the cured product layer 623 is formed on the blade tip surface side. That is, it is formed on the surface of the elastic member facing the member to be cleaned on the upstream side of the contact portion. The formed portion of the cured product layer 623 may be at least a part of the surface including the abutting portion and may be a portion including the abutting portion. A good effect can be obtained on the maintenance of the base material and the attitude control of the base material.
Further, as shown in FIG. 3B, the cured product layer may be formed on the lower surface side of the blade, that is, on the surface of the elastic member facing the member to be cleaned on the downstream side of the contact portion. The example shown in FIG. 1 corresponds to FIG. 3 (B).
In addition to the above, as shown in FIG. 3C, the cured product layer may be formed on a portion that covers the base material, that is, on the blade tip surface and the blade lower surface.

In FIG. 3, the layer thickness of the cured product layer at the contact portion is indicated by reference numeral d. As shown, it is the distance when a perpendicular line is drawn from the contact portion with respect to the base material.

<Manufacturing method of cleaning blade>
The method for producing a cleaning blade of the present invention includes a step of applying a curable composition to a base material, a step of curing the curable composition by heating or irradiation with active energy rays, and a step of cutting the base material. Have.

Conventionally, it is difficult to form a thick surface layer on the contact part with the previous blades manufactured by spraying or dip coating, and even if there is a film of 10 μm near the contact part, the contact part is filled with 1 to 3 μm. There wasn't. Since the surface layer is thin, the base rubber comes into contact with the image carrier, which tends to cause turning.

On the other hand, in the cleaning blade 62 of the present embodiment, for example, a curable composition for forming a cured product layer 623 was applied to a base material 622 made of urethane rubber, and the resin was cured by ultraviolet irradiation or heating. After that, it is cut by a cutting machine in which the blade is tilted so that the contact portion has an obtuse angle.
As a result, a thick film of 10 μm or more can be formed on the abutting portion as well, and an excellent effect can be exhibited in combination with the suppression of the tip ridge line turning due to the obtuse angle, and the turning is less likely to occur even after long-term use. , The tip is less likely to be missing.

In the present invention, the order of coating, curing and cutting of the substrate of the curable composition is not limited to the above. By applying a curable composition after cutting so that the contact portion of the base material has an obtuse angle, it is possible to form a thick film of 10 μm or more because the base material has an obtuse angle. ..

Examples of the coating method of the curable composition include bar coating, spray coating, dip coating, brush coating, screen printing and the like.
The thickness of the cured product layer includes the solid content concentration of the coating liquid, the solvent, the coating conditions (bar coat: gap, spray coat: discharge amount / distance / moving speed, dip coat: pulling speed, etc.), coating. It can be controlled by appropriately changing conditions such as the number of times.

[Member to be cleaned]
The shape, structure, size, and the like of the member to be cleaned are not particularly limited, 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, a sheet shape, and the like. The size of the member to be cleaned is not particularly limited and may be appropriately selected depending on the intended purpose, but it is more preferable that the member has a width similar to that of the elastic member 624.

The material of the member to be cleaned is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include metal, plastic and ceramic.
The member to be cleaned is not particularly limited and may be appropriately selected depending on the intended purpose. When the cleaning blade is applied to an image forming apparatus, for example, an image carrier or the like can be mentioned.

[Adhesion]
The deposit is not particularly limited as long as it adheres to the surface of the member to be cleaned and is to be removed by the cleaning blade 62. For example, toner, lubricant, inorganic fine particles, organic fine particles, dust, dust or a mixture thereof and the like can be mentioned. An example of a suitable removal target is a low-temperature fixable toner having a glass transition temperature of 50 ° C. or lower.

[Support member]
The shape, size, material, and the like of the support member 621 are not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the shape of the support member 621 include a flat plate shape, a strip shape, a sheet shape, and the like. The size of the support member 621 is not particularly limited and may be appropriately selected depending on the size of the member to be cleaned.

Examples of the material of the support member 621 include metal, plastic, and ceramic. Among these, a metal plate is preferable from the viewpoint of strength, and a steel plate such as stainless steel, an aluminum plate, and a phosphor bronze plate are particularly preferable.

〔Base material〕
As the material of the base material 622, a polyurethane compound (for example, polyurethane rubber, polyurethane elastomer, etc.) is selected from the viewpoint that high elasticity can be easily obtained.
The shape, size, structure, etc. of the base material 622 are not particularly limited and can be appropriately selected depending on the intended purpose. Examples of the shape of the base material 622 include a flat plate shape, a strip shape, a sheet shape, and the like. The size of the base material 622 can be appropriately selected according to the size of the member to be cleaned. Further, the base material 622 can be produced by a conventionally known composition and construction method.

[Curing product of curable composition]
Examples of the cured product of the curable composition in the cured product layer include a cured product that is cured by heating and a cured product that is cured by irradiating an active energy ray.
The heating can be appropriately changed and is not particularly limited. Examples thereof include aging treatment and annealing treatment in a constant temperature bath, and one type may be used, or two or more types may be used. You may. In addition, an initiator such as an epoxy curing agent may be used.

The cured product that is cured by irradiating it with active energy rays is a cured product obtained by irradiating an active energy ray-curable composition containing a polymerization initiator with active energy rays and curing it.
As the active energy rays, in addition to ultraviolet rays, those capable of imparting energy necessary for advancing the polymerization reaction of polymerizable components in the composition such as electron beams, α rays, β rays, γ rays, and X-rays. It suffices, and is not particularly limited. Further, in the case of ultraviolet irradiation, mercury-free is strongly desired from the viewpoint of environmental protection, and replacement with a GaN-based semiconductor ultraviolet light emitting device is very useful industrially and environmentally. Further, the ultraviolet light emitting diode (UV-LED) and the ultraviolet laser diode (UV-LD) are compact, have a long life, have high efficiency, and are low in cost, and are preferable as an ultraviolet light source.

The active energy ray-curable composition includes, for example, an acrylic resin (acrylic precursor), an epoxy resin (epoxy precursor), and the like.
Examples of the acrylic precursor include dipentaerythritol hexa (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol ethoxytetra (meth) acrylate, and trimethylpropanthry (meth) acrylate. , Trimethylol propaneethoxytri (meth) acrylate, 1,6-hexanediol di (meth) acrylate, ethoxylated bisphenol A di (meth) acrylate, propoxylated ethoxylated bisphenol A di (meth) acrylate, 1,4-butane Didiole (meth) acrylate, 1,5-pentanedioldi (meth) acrylate, 1,6-hexanedioldi (meth) acrylate, 1,7-heptanedioldi (meth) acrylate, 1,8-octanedioldi (Meta) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 1,11-undecanediol di (meth) acrylate, 1,18-octadecanediol di (meth) acrylate ) Acrylate, glycerin propoxytri (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, PO-modified neopentyl glycol di (meth) acrylate, PEG600 di (meth) acrylate, PEG400 di (meth) Meta) acrylate, PEG200 di (meth) acrylate, neopentyl glycol hydroxypivalic acid ester di (meth) acrylate, octyl / decyl (meth) acrylate, isobornyl (meth) acrylate, ethoxylated phenyl (meth) acrylate, 9,9- Bis [4- (2- (meth) acryloyloxyethoxy) phenyl] fluorene, tricyclodecanedimethanol diacrylate, tricyclodecanedimethanol dimethacrylate, 1,3-adamantan dimethanol diacrylate, 1,3-adamantandi Examples thereof include methanol dimethacrylate, 1,3,5-adamantantrimethanol triacrylate, and 1,3,5-adamantantrimethanol trimethacrylate.

As the acrylic precursor, one of the above-mentioned (meth) acrylic monomers and oligomers may be used alone, or two or more of them may be used in combination, but in the present embodiment, the acrylic precursor is bifunctional or higher. It is preferable to have.

The polymerization initiator may be one that can generate active species such as radicals and cations by the energy of the active energy ray and initiate the polymerization of the acrylic precursor (monomer or oligomer). As such a polymerization initiator, known radical polymerization initiators, cationic polymerization initiators, base generators and the like can be used alone or in combination of two or more, and among them, a radical polymerization initiator is used. Is preferable. Further, the polymerization initiator is preferably contained in an amount of 5 to 20% by mass with respect to the total mass (100% by mass) of the composition in order to obtain a sufficient curing rate.

Examples of the radical polymerization initiator include aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, thio compounds (thioxanthone compounds, thiophenyl group-containing compounds, etc.), hexaarylbiimidazole compounds, and the like. Examples thereof include ketooxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon halogen bond, and alkylamine compounds.

Further, as a method for confirming that the elastic member has a cured product layer made of a cured product of the curable composition from the cleaning blade which is the final product, for example, thermal decomposition GCMS and the like can be mentioned. By thermal decomposition GCMS, the mass spectrum of the abutting part and the elastic member are compared, and when the component that appears prominently in the mass spectrum of the abutting part contains fragment ions derived from the cured product mentioned in the previous section, it is heated. Alternatively, it can be said that it has a cured product layer made of a cured product obtained by irradiation with active energy rays.

<Image forming device and image forming method>
The image forming apparatus of this embodiment will be described with reference to FIGS. 4 and 5.
The image forming apparatus of the present embodiment includes an image carrier, a charging means for charging the surface of the image carrier, an exposure means for exposing the charged image carrier to form an electrostatic latent image, and the static electricity. A developing means for developing a latent image with toner to form a visible image, a transfer means for transferring the visible image to a recording medium, and a fixing means for fixing the transferred image transferred to the recording medium. The cleaning means for removing the toner remaining on the image carrier is provided, and the cleaning blade of the present invention described above is provided as the cleaning means.

Further, the image forming method of the present embodiment includes a charging step of charging the surface of the image carrier, an exposure step of exposing the charged image carrier to form an electrostatic latent image, and the electrostatic latent image. By a developing step of developing with toner to form a visible image, a transfer step of transferring the visible image to a recording medium, a fixing step of fixing the transferred image transferred to the recording medium, and a cleaning means. It has a cleaning step of removing toner remaining on the image carrier, and includes the above-mentioned cleaning blade of the present invention as the cleaning means.

FIG. 4 is a schematic configuration diagram showing an example of the image forming apparatus 500 according to the present embodiment. The image forming apparatus 500 includes four image forming units 1Y, 1C, 1M, and 1K for yellow, magenta, cyan, and black (hereinafter, may be referred to as Y, C, M, and K). .. These use Y, C, M, and K toners of different colors as the image forming substance for forming an image, but have the same configuration except for the above.

Above the four image forming units 1, a transfer unit 60 including an intermediate transfer belt 14 as an intermediate transfer body is arranged. The toner images of each color formed on the surfaces of the photoconductors 3Y, 3C, 3M, and 3K included in the image forming units 1Y, 1C, 1M, and 1K, which will be described in detail later, are superimposed on the surface of the intermediate transfer belt 14. It is a composition to be transferred.

Further, an optical writing unit 40 is arranged below the four image forming units 1. The optical writing unit 40, which is a latent image forming means, irradiates the photoconductors 3Y, 3C, 3M, and 3K of the image forming units 1Y, 1C, 1M, and 1K with the laser beam L emitted based on the image information. As a result, electrostatic latent images for Y, C, M, and K are formed on the photoconductors 3Y, 3C, 3M, and 3K. In the optical writing unit 40, the laser beam L emitted from the light source is polarized by the polygon mirror 41 rotationally driven by the motor, and the photoconductors 3Y, 3C, 3M, and 3K are passed through a plurality of optical lenses and mirrors. Is to irradiate. Instead of the above configuration, one that performs optical scanning by an LED array can also be adopted.

Below the optical writing unit 40, the first paper feed cassette 151 and the second paper feed cassette 152 are arranged so as to overlap each other in the vertical direction. A plurality of recording media P are housed in these paper cassettes in the form of a stack of paper stacks, and the top recording medium P includes a first paper feed roller 151a and a second paper feed. The rollers 152a are in contact with each other. When the first paper feed roller 151a is rotationally driven counterclockwise in FIG. 4 by the driving means, the top recording medium P in the first paper cassette 151 extends in the vertical direction on the right side in FIG. 4 of the cassette. It is discharged toward the paper feed path 153 arranged so as to exist. Further, when the second paper feed roller 152a is rotationally driven counterclockwise in FIG. 4 by the driving means, the top recording medium P in the second paper cassette 152 is discharged toward the paper feed path 153. ..

A plurality of transport roller pairs 154 are arranged in the paper feed path 153. The recording medium P fed into the paper feed path 153 is conveyed in the paper feed path 153 from the lower side to the upper side in FIG. 4 while being sandwiched between the rollers of the transfer rollers 154.
A resist roller pair 55 is arranged at the downstream end of the paper feed path 153 in the transport direction. The resist roller pair 55 temporarily stops the rotation of both rollers as soon as the recording medium P is sandwiched between the rollers and the recording medium P sent from the transport roller pair 154. Then, the recording medium P is sent out toward the secondary transfer nip described later at an appropriate timing.

FIG. 5 is an example of an image forming unit included in the image forming apparatus, and is a configuration diagram showing a schematic configuration of one of the four image forming units 1.
As shown in FIG. 5, the image forming unit 1 includes a drum-shaped photoconductor 3 as an image carrier. Although the photoconductor 3 has a drum-like shape, it may have a sheet-like shape or an endless belt-like shape.

A charging roller 4, a developing device 5, a primary transfer roller 7, a cleaning device 6, a lubricant applying device 10, a static elimination lamp, and the like are arranged around the photoconductor 3. The charging roller 4 is a charging member included in the charging device as the charging means, and the developing device 5 is a developing means for forming a latent image formed on the surface of the photoconductor 3 into a toner image. The primary transfer roller 7 is a primary transfer member provided in the primary transfer device as a primary transfer means for transferring the toner image on the surface of the photoconductor 3 to the intermediate transfer belt 14. The cleaning device 6 is a cleaning means for cleaning the toner remaining on the photoconductor 3 after the toner image is transferred to the intermediate transfer belt 14. The lubricant application device 10 is a lubricant application means for applying a lubricant on the surface of the photoconductor 3 after the cleaning device 6 has cleaned it. The static elimination lamp is a static elimination means for statically eliminating the surface potential of the photoconductor 3 after cleaning.

The charging roller 4 is arranged on the photoconductor 3 at a predetermined distance in a non-contact manner, and charges the photoconductor 3 to a predetermined polarity and a predetermined potential. The surface of the photoconductor 3 uniformly charged by the charging roller 4 is irradiated with laser light L from the optical writing unit 40, which is a latent image forming means, based on the image information to form an electrostatic latent image.

The developing device 5 has a developing roller 51 as a developing agent carrier. A development bias is applied to the developing roller 51 from a power source. Inside the casing of the developing apparatus 5, a supply screw 52 and a stirring screw 53 for stirring the developer contained in the casing while being conveyed in opposite directions are provided. In addition, a doctor 54 for regulating the developer carried on the developing roller 51 is also provided. The toner in the developer that is stirred and conveyed by the two screws of the supply screw 52 and the stirring screw 53 is charged to a predetermined polarity. Then, the developer is pumped onto the surface of the developing roller 51, and the pumped developer is regulated by the doctor 54, and the toner adheres to the latent image on the photoconductor 3 in the developing region facing the photoconductor 3. ..

The cleaning device 6 has 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 above-mentioned cleaning blade of the present invention.

The lubricant coating device 10 includes a solid lubricant 103, a lubricant pressure spring 103a, and the like, and uses a fur brush 101 as a coating brush for applying the solid lubricant 103 onto the photoconductor 3. The solid lubricant 103 is held by the bracket 103b and is pressurized to the fur brush 101 side by the lubricant pressure spring 103a. Then, the solid lubricant 103 is scraped by the fur brush 101 that rotates in the circumferential direction with respect to the rotation direction of the photoconductor 3, and the lubricant is applied onto the photoconductor 3. By applying a lubricant to the photoconductor, the friction coefficient on the surface of the photoconductor 3 is maintained at 0.2 or less during non-image formation. The lubricant applied on the photoconductor 3 can also be leveled with a blade.

The charging device is a non-contact proximity arrangement method in which the charging roller 4 is placed close to the photoconductor 3, but known charging devices include a corotron, a scorotron, and a solid state charger. Configurations can be used. Among these charging methods, the contact charging method or the non-contact close placement method is more desirable, and has merits such as high charging efficiency, low ozone generation amount, and miniaturization of the apparatus.

Light sources such as the laser light L light source and the static elimination lamp of the optical writing unit 40 include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), and electroluminescence (EL). ) And other light-emitting materials can be used in general.

Further, in order to irradiate only light in a desired wavelength range, various filters such as a sharp cut filter, a bandpass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can also be used.

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

The transfer unit 60 as the transfer means shown in FIG. 4 includes a belt cleaning unit 162, a first bracket 63, a second bracket 64, and the like, in addition to the intermediate transfer belt 14. Further, four primary transfer rollers 7Y, 7C, 7M, 7K, a secondary transfer backup roller 66, a drive 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 FIG. 4 by the rotational drive of the drive roller 67 while being stretched on these eight roller members. The four primary transfer rollers 7Y, 7C, 7M, and 7K form a primary transfer nip by sandwiching the intermediate transfer belt 14 that can be moved endlessly between the photoconductors 3Y, 3C, 3M, and 3K, respectively. ..

Then, a transfer bias having the opposite polarity (for example, plus) to the toner is applied to the back surface (loop inner peripheral surface) of the intermediate transfer belt 14. The intermediate transfer belt 14 is on the photoconductors 3Y, 3C, 3M, 3K on its front surface in the process of sequentially passing through the primary transfer nips for Y, C, M, and K as it moves endlessly. The Y, C, M, and K toner images are superimposed and primary transferred. As a result, a four-color superimposed toner image (hereinafter, may be referred to as a four-color toner image) is formed on the intermediate transfer belt 14.

The secondary transfer backup roller 66 forms a secondary transfer nip by sandwiching the intermediate transfer belt 14 with the secondary transfer roller 70 arranged on the outer side of the loop of the intermediate transfer belt 14. The resist roller pair 55 described above sends out the recording medium P sandwiched between the rollers toward the secondary transfer nip at a timing capable of synchronizing 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 nip pressure. , The secondary transfer is collectively transferred to the recording medium P in the secondary transfer nip. Then, in combination with the white color of the recording medium P, a full-color toner image is obtained.

The transfer residual toner that has not been transferred to the recording medium P is attached to the intermediate transfer belt 14 after passing through the secondary transfer nip. It is cleaned by the belt cleaning unit 162. In the belt cleaning unit 162, the belt cleaning blade 162a is brought into contact with the front surface of the intermediate transfer belt 14, thereby scraping 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 drive is turned on and off. When forming a monochrome image, the image forming apparatus 500 rotates the first bracket 63 slightly counterclockwise in FIG. 4 by driving the above-mentioned solenoid. By this rotation, the primary transfer rollers 7Y, 7C, 7M for Y, C, and M are revolved counterclockwise in FIG. 4 around the rotation axis of the auxiliary roller 68, so that the intermediate transfer belt 14 is rotated Y, C. , M Photoreceptors 3Y, 3C, 3M away from.

Then, of the four image forming units 1Y, 1C, 1M, and 1K, only the image forming unit 1K for K is driven to form a monochrome image. As a result, it is possible to avoid wearing of each member constituting the image forming unit 1 by unnecessarily driving the image forming unit 1 for Y, C, and M at the time of forming a monochrome image.

A fixing unit 80 is arranged above the secondary transfer nip in FIG. 4. The fixing unit 80 includes a pressure heating roller 81 including a heat generating source such as a halogen lamp, and a fixing belt unit 82. The fixing belt unit 82 includes a fixing belt 84 as a fixing member, a heating roller 83 including a heat generating source such as a halogen lamp, a tension roller 85, a drive roller 86, a temperature sensor, and the like.

Then, the endless fixing belt 84 is endlessly moved in the counterclockwise direction in FIG. 4 while being stretched by the heating roller 83, the tension roller 85, and the drive roller 86. In the process of this endless movement, the fixing belt 84 is heated from the back surface side by the heating roller 83. The pressurizing heating roller 81, which is rotationally driven in the clockwise direction in FIG. 4, is in contact with the portion where the fixing belt 84 heated in this manner is hung on the heating roller 83 from the front surface side. As a result, a fixing nip is formed in which the pressure heating roller 81 and the fixing belt 84 come into contact with each other.

A temperature sensor is arranged on the outside of the loop of the fixing belt 84 so as to face the front surface of the fixing belt 84 via 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 fixed power supply circuit. The fixing power supply circuit controls on / off of power supply to the heat generation source included in the heating roller 83 and the heat generation source included in the pressurizing heating roller 81 based on the detection result by the temperature sensor.

The recording medium P that has passed through the secondary transfer nip described above is separated from the intermediate transfer belt 14 and then sent into the fixing unit 80. Then, in the process of being conveyed from the lower side to the upper side in FIG. 5 while being sandwiched between the fixing nips in the fixing unit 80, the full-color toner image is fixed to the recording medium P by being heated and pressed by the fixing belt 84. Will be done.

The recording medium P thus fixed is discharged to the outside of the image forming apparatus after passing between the paper ejection rollers and the rollers 87. A stack portion 88 is formed on the upper surface of the housing of the image forming apparatus 500 main body, and the recording medium P discharged to the outside of the image forming apparatus by the paper ejection roller pair 87 is sequentially stacked on the stack portion 88.

Four toner cartridges 100Y, 100C, 100M, 100K for accommodating Y, C, M, and K toners are arranged above the transfer unit 60. The Y, C, M, K toners in the toner cartridges 100Y, 100C, 100M, 100K are appropriately supplied to the developing apparatus of the image forming unit 1Y, 1C, 1M, 1K. These toner cartridges 100Y, 100C, 100M, 100K can be attached to and detached from the image forming apparatus main body independently of the image forming units 1Y, 1C, 1M, 1K.

Next, the image forming operation in the image forming apparatus 500 will be described.
First, 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 predetermined timings, respectively. Similarly, a predetermined voltage or current is sequentially applied to each of the light sources such as the optical writing unit 40 and the static elimination lamp at a predetermined timing. Further, in synchronization with this, the photoconductor 3 is rotationally driven in the direction of the arrow in FIG. 5 by the photoconductor drive motor as a driving means.

When the photoconductor 3 rotates in the direction of the arrow in FIG. 5, 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 of the surface of the photoconductor 3 irradiated with the laser beam L is statically eliminated to form an electrostatic latent image. ..

The surface of the photoconductor 3 on which the electrostatic latent image is formed is rubbed by a magnetic brush of a developer 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 is moved to the electrostatic latent image side by a predetermined development bias applied to the developing roller 51, and is made into a toner image (development). In each image forming unit 1, the same image forming process is executed, and toner images of each color are formed on the surfaces of the photoconductors 3Y, 3C, 3M, 3K of each image forming unit 1Y, 1C, 1M, 1K. ..

As described above, in the image forming apparatus 500, the electrostatic latent image formed on the photoconductor 3 is reverse-developed by the developing apparatus 5 with the negatively charged toner. In the present embodiment, an example using a non-contact charging roller method of N / P (negative / positive: toner adheres to a place where the potential is low) has been described, but the present invention is not limited to this.

The toner images of each color formed on the surfaces of the photoconductors 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, and is fed to the secondary transfer nip via the rollers of the resist roller vs. 55. It is transferred to the recording medium P to be printed. At this time, the recording medium P is temporarily stopped in a state of being sandwiched between the resist roller pairs 55, and is supplied to the secondary transfer nip in synchronization with the image tip on the intermediate transfer belt 14. The recording medium P on which the toner image is transferred is separated from the intermediate transfer belt 14 and conveyed to the fixing unit 80.

Then, when the recording medium P on which the toner image is transferred passes through the fixing unit 80, the toner image is fixed on the recording medium P by the action of heat and pressure, and the recording medium P on which the toner image is fixed is an image. It is discharged to the outside of the forming device 500 and stacked on the stack portion 88.

On the other hand, on the surface of the intermediate transfer belt 14 on which the toner image is transferred to the recording medium P by the secondary transfer nip, the transfer residual toner on the surface is removed by the belt cleaning unit 162.
Further, on the surface of the photoconductor 3 on which the toner images of each color were transferred to the intermediate transfer belt 14 by the primary transfer nip, the residual toner after the transfer was removed by the cleaning device 6, and the lubricant was applied by the lubricant applying device 10. After that, the static electricity is removed by the static elimination lamp.

The toner used in the image forming apparatus 500 is a polymerized toner (glass transition) produced by a suspension polymerization method, an emulsification polymerization method, or a dispersion polymerization method, which tends to have a high circular shape and a small particle size, from the viewpoint of improving image quality. It is preferable to use a low temperature fixable toner having a temperature of 50 ° C. or lower). Among these, from the viewpoint of forming a high-resolution image, it is preferable to use a polymerized toner having an average circularity of 0.97 or more and a volume average particle size of 5.5 μm or less.

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 alkylbenzenesulfonate, as a dispersant is added to 100 to 150 ml of water in which the impure solid matter has been removed in advance in the container, and further, a measurement sample (toner) is added. ) Is added in an amount of about 0.1 to 0.5 g. Then, the suspension in which the toner was dispersed was dispersed in an ultrasonic disperser for about 1 to 3 minutes so that the dispersion concentration was 3000 to 10,000 / μl, and the suspension was set in the above-mentioned analyzer. Then, the shape and distribution of the toner are measured. Then, based on this measurement result, the outer peripheral length of the actual toner projection shape shown in FIG. 6 (A) is C1, the projected area thereof is S, and the outer circumference of the perfect circle shown in FIG. 6 (B), which is the same as the projected area S. C2 / C1 when the length was C2 was obtained, and the average value thereof was defined as circularity.

Further, in the cleaning step of the image forming method of the present embodiment, it is preferable that the elastic member of the cleaning blade comes into contact with the surface of the image carrier with a pressing force of 10 N / m or more and 100 N / m or less. If the pressing force is less than 10 N / m, cleaning failure is likely to occur due to the passage of toner at the contact portion where the elastic member of the cleaning blade comes into contact with the surface of the image carrier, and if it exceeds 100 N / m, the contact portion of the contact portion is likely to be defective. The cleaning blade may roll up due to the increase in frictional force. The pressing force is more preferably 10 N / m or more and 50 N / m or less.
The pressing force can be measured, for example, by using a measuring device incorporating a small compression type load cell manufactured by Kyowa Electric Co., Ltd.

<Process cartridge>
The process cartridge of the present embodiment includes an image carrier, cleaning means for removing deposits adhering to the surface of the image carrier, and other means as needed. Specifically, the process cartridge of the present embodiment incorporates an image carrier and a cleaning blade of the present invention, and appropriately includes means such as charging means, exposure means, developing means, transfer means, and static elimination means. It is a device (part) that is housed in a frame and can be attached to and detached from the image forming device main body.

As shown in FIG. 5, the image forming unit 1 of the image forming apparatus 500 includes a photoconductor 3, a charging roller 4, a developing apparatus 5, a cleaning apparatus 6, a lubricant coating apparatus 10, and the like as process means in the frame 2. Has been done. The image forming unit 1 is integrally removable from the image forming apparatus 500 main body shown in FIG. 5 as a process cartridge.

In the image forming apparatus 500, the image forming unit 1 integrally replaces the photoconductor 3 as a process cartridge and the process means, but the photoconductor 3, the charging roller 4, the developing device 5, and the cleaning device 6 are used. , The configuration may be such that the unit such as the lubricant coating device 10 is replaced with a new one.

The cleaning blade 62 of the present embodiment does not cause pulling in at the contact portion of the elastic member 624, so that it is possible to suppress the occurrence of local chipping that causes cleaning failure. Therefore, although it can be widely used in various fields, it is particularly preferably used for the above-mentioned image forming apparatus and process cartridge.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to the following Examples.

(Making toner)
Toner was prepared by the following polymerization method (Japanese Unexamined Patent Publication No. 2014-92633).

<Manufacturing of urethane-modified crystalline polyester resin A-2>
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 202 parts by mass (1.00 mol) of sebacic acid, 15 parts by mass (0.10 mol) of adipic acid, and 177 parts by mass (1) of 1,6-hexanediol. .50 mol) and 0.5 part by mass of tetrabutoxytitanate as a condensation catalyst were added, and the reaction was carried out at 180 ° C. under a nitrogen stream for 8 hours while distilling off the produced water. Then, while gradually raising the temperature to 220 ° C., the water produced under a nitrogen stream and 1,6-hexanediol were reacted for 4 hours while distilling off, and the Mw was about 12 under a reduced pressure of 5 to 20 mmHg. The reaction was carried out until it reached 000, and [crystalline polyester resin A'-2] was obtained. The obtained [crystalline polyester resin A'-2] was Mw12,000.

Subsequently, the obtained [crystalline polyester resin A'-2] was transferred into a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and 350 parts by mass of ethyl acetate, 4,4'-diphenylmethane diisocyanate ( MDI) 30 parts by mass (0.12 mol) was added, and the mixture was reacted at 80 ° C. for 5 hours under a nitrogen stream. Then, ethyl acetate was distilled off under reduced pressure to obtain [urethane-modified crystalline polyester resin A-2]. The obtained [urethane-modified crystalline polyester resin A-2] had a Mw of 22,000 and a melting point of 62 ° C.

<Manufacturing of crystalline resin precursor B'-5>
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 202 parts by mass (1.00 mol) of sebacic acid, 122 parts by mass (1.03 mol) of 1,6-hexanediol, and titanium dihydroxybis as a condensation catalyst. 0.5 part by mass of (triethanolamineate) was added, and the reaction was carried out at 180 ° C. under a nitrogen stream for 8 hours while distilling off the produced water. Then, while gradually raising the temperature to 220 ° C., the reaction was carried out for 4 hours while distilling off water and 1,6-hexanediol produced under a nitrogen stream, and the Mw was about 25 under a reduced pressure of 5 to 20 mmHg. The reaction was carried out until it reached 000, and a [crystalline resin] was obtained.

The obtained [crystalline resin] was transferred to a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and 300 parts by mass of ethyl acetate and 27 parts by mass (0.16 mol) of hexamethylene diisocyanate (HDI) were added. , The reaction was carried out at 80 ° C. for 5 hours under a nitrogen stream to obtain a 50% by mass ethyl acetate solution of [crystalline resin precursor B'-5] having an isocyanate group at the terminal. 10 parts by mass of the obtained ethyl acetate solution of [crystalline resin precursor B'-5] was mixed with 10 parts by mass of tetrahydrofuran (THF), 1 part by mass of dibutylamine was added thereto, and the mixture was stirred for 2 hours. .. As a result of GPC measurement using the obtained solution as a sample, the Mw of [crystalline resin precursor B'-5] was 54,000. Further, as a result of DSC measurement on the sample obtained by removing the solvent from this solution, the melting point of [Crystallinic resin precursor B'-5] was 57 ° C.

<Manufacturing of amorphous resin C-1>
222 parts by mass of bisphenol A EO 2 mol adduct, 129 parts by mass of bisphenol A PO 2 mol adduct, 166 parts by mass of isophthalic acid, and 0.5 parts by mass of tetrabutoxytitanate in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen insertion tube. Was charged, and the reaction was carried out at 230 ° C. and normal pressure under a nitrogen stream for 8 hours while distilling off the generated water. Then, the reaction was carried out under a reduced pressure of 5 to 20 mmHg, and when the acid value reached 2, the mixture was cooled to 180 ° C., 35 parts by mass of trimellitic anhydride was added, and the reaction was carried out at normal pressure for 3 hours. Resin C-1] was obtained. The obtained [amorphous resin C-1] had a Mw of 8,000 and a glass transition temperature (Tg) of 62 ° C.

<Manufacturing of graft polymer>
In a reaction vessel set with a stirring rod and a thermometer, 480 parts by mass of xylene and 100 parts by mass of low molecular weight polyethylene (Sunwax LEL-400 manufactured by Sanyo Kasei Kogyo Co., Ltd .: softening point 128 ° C.) were put and sufficiently dissolved to replace nitrogen. After that, a mixed solution of 740 parts by mass of styrene, 100 parts by mass of acrylonitrile, 60 parts by mass of butyl acrylate, 36 parts by mass of di-t-butylperoxyhexahydroterephthalate, and 100 parts by mass of xylene was added dropwise at 170 ° C. for 3 hours. And polymerized, and kept at this temperature for 30 minutes. Then, the solvent was removed to synthesize a [graft polymer]. The obtained [graft polymer] had Mw24,000 and Tg67 ° C.

<Preparation of release agent dispersion liquid (1)>
Paraffin wax (manufactured by Nippon Seiko Co., Ltd., HNP-9, hydrocarbon wax, melting point 75 ° C., SP value 8.8) 50 parts by mass, [graft polymer] 30 parts by mass in a container with a stirring rod and a thermometer set. , And 420 parts by mass of ethyl acetate, heated to 80 ° C. with stirring, held at 80 ° C. for 5 hours, cooled to 30 ° C. in 1 hour, and used a bead mill (Ultra Viscomill, manufactured by Imex). Then, the liquid feeding rate was 1 kg / hr, the disk peripheral speed was 6 m / sec, and 0.5 mm zirconia beads were filled in 80% by volume, and dispersion was carried out under the conditions of 3 passes to obtain a [release agent dispersion liquid (1)].

<Making a masterbatch>
-Urethane-modified crystalline polyester resin A-2 (binding resin) 100 parts by mass-Carbon black (Printex35, manufactured by Degussa) 100 parts by mass (DBP oil absorption: 42 mL / 100 g, pH: 9.5)
50 parts by mass of ion-exchanged water The above raw materials were mixed using a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.). The resulting mixture was kneaded using two rolls. The kneading temperature started from 90 ° C., and then gradually cooled to 50 ° C. The obtained kneaded product was crushed with a palperizer (manufactured by Hosokawa Micron Co., Ltd.) to prepare a [master batch (2)].

<Preparation of oil phase (1)>
Put 31.5 parts by mass of [Urethane-modified crystalline polyester resin A-2] in a container equipped with a thermometer and a stirrer, add ethyl acetate in an amount that makes the solid content concentration 50% by mass, and add the melting point of the resin. It was heated to the above and dissolved well. To this, 100 parts by mass of a 50 mass% ethyl acetate solution of [non-crystalline resin C-1], 60 parts by mass of [release agent dispersion (1)], and 12 parts by mass of [master batch (2)] were added. The mixture was stirred at 50 ° C. with a TK homomixer (manufactured by Primix Co., Ltd.) at a rotation speed of 5,000 rpm, and uniformly dissolved and dispersed to obtain [oil phase (1')]. The temperature of the [oil phase (1')] was kept at 50 ° C. in the container and used within 5 hours from the preparation so as not to crystallize.
Next, immediately before the preparation of the toner base, which will be described later, 25 parts of an ethyl acetate solution of [crystalline resin precursor B'-5] was added to 235 parts of the [oil phase (1')] kept at 50 ° C. The mixture was stirred with a TK homomixer (manufactured by Primix Corporation) at a rotation speed of 5,000 rpm to uniformly dissolve and disperse to prepare [oil phase (1)].

<Manufacturing of aqueous dispersion of resin fine particles>
600 parts by mass of water, 120 parts by mass of styrene, 100 parts by mass of methacrylic acid, 45 parts by mass of butyl acrylate, sodium alkylallyl sulfosuccinate (eleminol JS-2, Sanyo Kasei Kogyo) in a reaction vessel with a stirring rod and a thermometer set. (Manufactured) 10 parts by mass and 1 part by mass of ammonium persulfate were charged and stirred at 400 rpm for 20 minutes to obtain a white emulsion. The emulsion was heated to a temperature inside the system of 75 ° C. and reacted for 6 hours. Further, 30 parts by mass of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 6 hours to obtain a [aqueous dispersion of resin fine particles]. The volume average particle diameter of the particles contained in this [aqueous dispersion of resin fine particles] was 80 nm, the weight average molecular weight of the resin content was 160,000, and Tg was 74 ° C.

<Preparation of aqueous phase (1)>
990 parts by mass of water, 83 parts by mass of [aqueous dispersion of resin fine particles], 37 parts by mass of an aqueous solution of 48.5% by mass of sodium dodecyldiphenyl ether disulfonate (Eleminol MON-7, manufactured by Sanyo Kasei Kogyo Co., Ltd.), and 90 parts by ethyl acetate. The parts by mass were mixed and stirred to obtain [aqueous phase (1)].

<Preparation of toner base (1)>
[Aquatic phase (1)] 520 parts by mass was placed in another container in which a stirrer and a thermometer were set, and heated to 40 ° C. To 235 parts by mass of [oil phase (1)] maintained at 50 ° C., 25 parts by mass of an ethyl acetate solution of [crystalline resin precursor B'-5] was added, and a TK homomixer (manufactured by Tokushu Kagaku Co., Ltd.) was added. ) Was stirred at a rotation speed of 5,000 rpm to uniformly dissolve and disperse to prepare an [oil phase (1')]. Add [Oil phase (1')] while stirring [Aquatic phase (1)] kept at 40 to 50 ° C. with a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) at 13,000 rpm. Then, it was emulsified for 1 minute to obtain [emulsified slurry 1].

Next, [emulsified slurry 1] was put into a container in which a stirrer and a thermometer were set, and the solvent was removed at 60 ° C. for 6 hours to obtain [slurry 1]. After the obtained [slurry 1] was filtered under reduced pressure, the following washing treatment was performed.
(1) 100 parts by mass of ion-exchanged water was added to the filtered cake, mixed with a TK homomixer (rotation speed 6,000 rpm for 5 minutes), and then filtered.
(2) 100 parts by mass of a 10 mass% sodium hydroxide aqueous solution was added to the filtered cake of (1), mixed with a TK homomixer (rotation speed: 6,000 rpm for 10 minutes), and then filtered under reduced pressure.
(3) 100 parts by mass of 10% by mass hydrochloric acid was added to the filtered cake of (2), mixed with a TK homomixer (rotation speed: 6,000 rpm for 5 minutes), and then filtered.
(4) Add 300 parts by mass of ion-exchanged water to the filtered cake of (3) above, mix with a TK homomixer (rotation speed: 6,000 rpm for 5 minutes), and then filter twice to perform the filtration cake (1). Got

The obtained filtered cake (1) was dried in a circulation dryer at 45 ° C. for 48 hours. Then, the toner matrix particles (1) were prepared by sieving with a mesh having a mesh size of 75 μm. The obtained toner matrix particles (1) had an average circularity of 0.98 and a volume average particle size of 4.9 μm.

<Making toner>
100 parts by mass of the obtained toner matrix particles (1) and the following external preparation are mixed for 30 seconds at a peripheral speed of 30 m / sec using a Henschel mixer (manufactured by Mitsui Mining Co., Ltd.), and the process is rested for 1 minute. After 5 cycles, the toner (1) was prepared by sieving with a mesh having a mesh size of 35 μm. The glass transition temperature of the obtained toner was 50 ° C.

[External agent]
Small particle size silica 1.5 parts by mass (manufactured by Clariant, H2000)
Small particle size Titanium oxide 0.5 parts by mass (manufactured by TAYCA, MT-150AI)
Large particle size silica 1.0 part by mass (manufactured by Denki Kagaku Kogyo Co., Ltd., UFP-30H)

(Preparation of base material)
As the base material of the elastic member, two urethane rubbers (base materials 1 and 2) having JIS-A hardness, 23 ° C. elastic modulus, and Martens hardness (HM) shown in Table 1 below were prepared. The measurement method is shown below.

<JIS-A hardness>
The JIS-A hardness on the lower surface side of the base material of the elastic member was measured according to JIS K6253 using a micro rubber hardness tester MD-1 manufactured by Kosei Keiki Co., Ltd. (23 ° C.).

<Repulsive modulus>
The elastic modulus of the base material of the elastic member was 23 ° C., and No. 1 manufactured by Toyo Seiki Seisakusho Co., Ltd. Measurements were made according to JIS K6255 using a 221 resilience tester. The sample used was a stack of sheets having a thickness of 2 mm so as to have a thickness of 4 mm or more.

<Martens hardness (HM)>
Indentation measurement was performed at a position 100 μm from the tip ridge of the base material using a micro hardness tester to determine the Martens hardness (HM). The microhardness meter was an HM-2000 manufactured by Fisher Instruments, Inc., and the Vickers indenter was pushed in for 10 seconds with a force of 1.0 mN, held for 5 seconds, and unloaded for 10 seconds with a force of 1.0 mN.

(Example 1)
<Manufacturing of cleaning blade 1>
A sheet-shaped polyurethane rubber base material 1 having a thickness of 1.8 mm was cut by tilting the blade so that the angle of contact with the member to be cleaned was 110 °. The curable composition shown in Table 4 (see Tables 2 and 3 for details) was spray-coated on the tip ridge of the base 1 at a spray gun moving speed of 5 mm / s from the tip surface of the base material. Overcoating was performed. Then, after aging treatment in a constant temperature bath at 110 ° C. for 3 hours, annealing treatment was performed in a constant temperature bath at 165 ° C. for 2 hours and cured to form a cured product layer. The cross section in the vicinity of the contact portion has the configuration shown in FIG. 3 (C).
Next, the elastic member having the cured product layer formed on the contact portion was fixed to the sheet metal holder (support member) with an adhesive so that the elastic member could be mounted on the color multifunction device (imagio MP C4500, manufactured by Ricoh Co., Ltd.).
As described above, the cleaning blade 1 having the cured product layer formed on the abutting portion was produced.

<Assembly of image forming device>
The produced cleaning blade 1 was attached to a color multifunction device (imageo MP C4500, manufactured by Ricoh Co., Ltd.) (the printer unit has the same configuration as the image forming apparatus 500 shown in FIG. 4), and the image forming apparatus of Example 1 was assembled.
The cleaning blade was attached to the image forming apparatus so that the linear pressure was 20 g / cm. Further, the device is provided with a lubricant coating device on the surface of the photoconductor, and the static friction coefficient of the surface of the photoconductor is maintained at 0.2 or less at the time of non-image formation by applying the lubricant. The method for measuring the coefficient of static friction on the surface of the photoconductor is described in the Euler belt method, for example, in paragraph No. 0046 of JP-A-9-166919.

The prepared cleaning blade was measured and evaluated as follows. The results are shown in the table below.

(Example 2)
<Manufacturing of cleaning blade 2>
In Example 1, as shown in Table 4 below, the composition of the curable composition, the initiator, the internal angle D, and the thickness of the cured product layer were changed, and the aging and annealing treatments were further changed to annealing treatments at 80 ° C. for 1 hour. A cleaning blade 2 was produced in the same manner as in Example 1 except for the above.
The produced cleaning blade was attached to the color multifunction device in the same manner as the cleaning blade 1 of Example 1, and the image forming apparatus was assembled.

(Examples 3 to 12)
<Manufacturing of cleaning blades 3 to 12>
In Example 1, as shown in Tables 4 and 5 below, coating was performed by changing the base material, the composition of the cured composition, the region where the cured product layer was formed, the internal angle D, and the thickness of the cured product layer.
The curing conditions were different from those of Example 1, and ultraviolet exposure was performed using a high-pressure mercury lamp so that the ^{integrated UV irradiation amount was 6000 mJ / cm 2.} Ultraviolet exposure (irradiation atmosphere) was performed in a nitrogen atmosphere. At this time, while the high-pressure mercury lamp is located above, the tip ridge of the blade is set upward and irradiated with ultraviolet rays so that the tip ridge is efficiently irradiated with ultraviolet rays.
Regarding the measurement of the integrated ultraviolet light amount, the integrated ultraviolet light amount at a wavelength of 254 nm was measured using an ultraviolet integrated photometer UIT-250 (manufactured by Ushio, Inc.). At this time, the measurement was performed so that the sensor portion of the integrated photometer was at the same height as the tip ridge portion of the cleaning blade.

Further, in Examples 5 to 10, the cross section in the vicinity of the contact portion was configured as shown in FIG. 3 (A), and Example 12 had a configuration shown in FIG. 3 (B). Further, in Examples 5 to 10, the curable composition was spray-coated, cured to form a cured product layer, and then cut to prepare a cleaning blade.

Each of the produced cleaning blades was attached to a color multifunction device in the same manner as the cleaning blade 1 of Example 1, and an image forming apparatus was assembled.

(Comparative Example 1)
<Manufacturing of cleaning blade 13>
In the cleaning blade 1 of Example 1, the cleaning blade 13 of Comparative Example 1 was produced in the same manner as in Example 1 except that the internal angle D was changed to 90 ° as shown in the cross-sectional view of FIG.
The produced cleaning blade was attached to the color multifunction device in the same manner as the cleaning blade 1 of Example 1, and the image forming apparatus was assembled.

(Comparative Examples 2 and 3)
<Manufacturing of cleaning blades 14 and 15>
In Example 3, after the aging treatment was performed in a constant temperature bath at 110 ° C. for 0.5 hour, the internal angle D and the layer thickness of the cured product layer were changed as shown in Table 6 instead of the method of irradiating with ultraviolet rays, and the cleaning blade was used. Cleaning blades 14 and 15 were produced in the same manner as in Example 3 except that the cross-sectional shape was changed as shown in FIG.
Each of the produced cleaning blades was attached to the color multifunction device in the same manner as the cleaning blade 1 of Example 1, and the image forming apparatus was assembled.

(Comparative Examples 4 to 7)
<Manufacturing of cleaning blades 16 to 19>
In Comparative Example 2, the cleaning blade is the same as in Comparative Example 2 except that the internal angle D and the layer thickness of the cured product layer are changed as shown in Table 6 and the cross-sectional shape of the cleaning blade is changed as shown in FIG. 16 to 19 were prepared.
Each of the produced cleaning blades was attached to the color multifunction device in the same manner as the cleaning blade 1 of Example 1, and the image forming apparatus was assembled.

(Comparative Example 8)
<Manufacturing of cleaning blade 20>
A cleaning blade 20 was produced in the same manner as in Comparative Example 6 except that the cured product layer was not formed in Comparative Example 6.
The produced cleaning blade was attached to the color multifunction device in the same manner as the cleaning blade 1 of Example 1, and the image forming apparatus was assembled.

(Measurement and evaluation)
<Thickness of cured product layer>
FIG. 8 is a cross-sectional view for explaining a measurement point of the thickness at the contact portion of the cleaning blade. FIG. 8 (A) is another cross-sectional view of FIG. 3 (B). As shown by the broken line in FIG. 8, when the elastic member is sliced in a plane orthogonal to the longitudinal direction, a cross section as shown in FIG. 8B is obtained, and the cross section is turned upward and the digital microscope is used. It was observed with a VHX-2000 (manufactured by KEYENCE). The measurement point is the blade contact portion (tip ridgeline portion) of the cross section. In this way, the layer thickness d shown in FIG. 8B is obtained. The measurement was performed at 10 points, and the average value was calculated.
As a method of cutting the elastic member into round slices, the elastic member was cut with a razor perpendicular to the longitudinal direction of the elastic member so that the thickness of the elastic member in the longitudinal direction was 3 mm. At that time, if a vertical slicer is used, the cross section can be cut more cleanly. The position in the longitudinal direction in which the elastic member was sliced was set to a position excluding the 2 cm portions at both ends.

<Martens hardness (HM) of the cured product layer>
After the cured product layer was formed, indentation measurement was performed at a position 100 μm from the tip ridge of the cured product layer using a microhardness meter to determine the Martens hardness (HM). The microhardness meter was an HM-2000 manufactured by Fisher Instruments, Inc., and the Vickers indenter was pushed in for 10 seconds with a force of 1.0 mN, held for 5 seconds, and unloaded for 10 seconds with a force of 1.0 mN.
Tables 4 to 6 below show the results of comparing the Martens hardness of the cured product layer with the Martens hardness of the base material. The case where the difference in Martens hardness between the cured product layer and the base material was ^{within ± 0.5 N / mm 2} was defined as “equivalent”.

<Image formation conditions>
Using the above image forming apparatus, laboratory environment: 65% RH at 21 ° C., paper passing conditions: image area ratio 5%, 3 prints / job, 50,000 sheets (A4 size horizontal) are output, and the following Evaluation was performed.

<Evaluation of deposits (cleanability)>
After outputting the above 50,000 images, the photoconductor was taken out from the evaluation machine after the image output and observed with a laser microscope VK-9510 (manufactured by KEYENCE CORPORATION). The cleanability was evaluated based on the number of surface abnormalities existing on the surface of the photoconductor. If there are deposits such as toner on the surface of the photoconductor, it is observed as a surface abnormality. Below, "◎", "○", and "△" are acceptable, and "×" is unacceptable.

[Evaluation criteria]
◎: Less than 5 places ○: 5 places or more and less than 10 places △: 10 places or more and less than 15 places ×: 15 places or more

<Abnormal noise>
As an evaluation of the abnormal noise, the generated sound was collected by the digital sound level meter CENTER325 at the time of image output of the cleanability evaluation, and judged by the following evaluation criteria. At this time, even if there is a difference in sound such as high frequency or low frequency, the presence or absence of occurrence as an abnormal sound was evaluated regardless of the sound emitted from the blade. “○” and “△” are acceptable, and “×” is unacceptable.

[Evaluation criteria]
◯: Less than 50db Δ: 50db or more and less than 60db ×: 60db or more

<Missing tip ridge>
After outputting the above 50,000 sheets, the presence or absence of a missing tip ridge in the elastic member was observed from the tip surface side of the elastic member with a laser microscope VK-9510 (manufactured by KEYENCE CORPORATION). The central portion of the cleaning blade in the longitudinal direction was observed in three visual fields (1 visual field: 100 μm square), and the missing portion of the tip ridge line portion was observed and judged according to the following evaluation criteria.

[Evaluation criteria]
○: Less than 3 places △: 3 places or more and less than 10 places ×: 10 places or more

The details of the materials used for producing the cleaning blades in the above Examples and Comparative Examples are shown in Tables 2 and 3. The compositions and measurement results of the cleaning blades obtained in the above Examples and Comparative Examples are shown in Tables 4 to 6. The evaluation results of the cleaning blades obtained in the above Examples and Comparative Examples are shown in Tables 7 and 8.

In the case of right-angle contact as in Comparative Examples 2 and 3, it is considered that as a result of the contact portion being crushed and interfering with the cured product layer, the evaluation result of abnormal noise as shown in Table 8 was obtained.

1 Image-forming unit 2 Frame 3 Photoreceptor 4 Charging roller 5 Developing device 6 Cleaning device 7 Primary transfer roller 10 Lubricating device 14 Intermediate transfer belt 40 Optical writing unit 41 Polygon mirror 51 Developing roller 52 Supply screw 53 Stirring screw 54 Doctor 55 Resist Roller vs. 60 Transfer Unit 62 Cleaning Blade 62a Blade Tip Surface 62b Blade Bottom Side 62c Tip Ridge 621 Support Member 622 Base Material 623 Hardened Material Layer 624 Elastic Member 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 Pressurized heating roller 82 Fixing belt unit 83 Heating roller 84 Fixing belt 85 Tension roller 86 Drive roller 87 Paper discharge roller vs. 88 Stack part 100 Toner cartridge 101 fur Brush 103 Solid Lubrication 103a Lubricant Pressurized Spring 103b Bracket 123 Image Carrier 151 First Paper Cassette 151a First Paper Roller 152 Second Paper Cassette 152a Second Paper Roller 153 Paper Path 154 Transport Roller Pair 162 Belt cleaning unit 162a Belt cleaning blade 500 Image forming device (printer)

Japanese Patent No. 3602898 Japanese Unexamined Patent Publication No. 2004-233818 Japanese Patent No. 5532378 Japanese Patent No. 2962843 Japanese Unexamined Patent Publication No. 2013-214037 JP-A-2010-156778

Claims (8)

An elastic member that comes into contact with the surface of the member to be cleaned and removes deposits adhering to the surface of the member to be cleaned is provided.
The elastic member has a base material and a cured product layer made of a cured product of a curable composition.
The cured product layer is formed including the contact portion on at least a part of the surface including the contact portion that comes into contact with the member to be cleaned, and the layer thickness of the cured product layer at the contact portion is 10 μm or more and 100 μm or less. And
The angle formed by the surface of the elastic member facing the member to be cleaned on the upstream side of the contact portion and the surface of the elastic member facing the member to be cleaned on the downstream side of the contact portion is 110 ° or 145 ° Ri der below,
Cleaning blade Martens hardness of the cured product layer has a 3N / mm ² or more, the Martens hardness of said substrate is 2N / mm ² or less der Rukoto. The cleaning blade according to claim 1, wherein the formed angle is 120 ° or more and 135 ° or less. The cleaning blade according to claim 1 or 2, wherein the thickness of the cured product layer at the contact portion is 12 μm or more and 65 μm or less. The cleaning blade according to any one of claims 1 to 3 , wherein the cured product layer is formed in a region of 1 to 7 mm from the contact portion. The method for manufacturing a cleaning blade according to any one of claims 1 to 4.
The step of applying the curable composition to the base material and
A step of curing the curable composition by heating or irradiation with active energy rays, and
A method for manufacturing a cleaning blade, which comprises a step of cutting the base material. A process cartridge having an image carrier and a cleaning means for removing deposits adhering to the surface of the image carrier.
A process cartridge, wherein the cleaning means includes the cleaning blade according to any one of claims 1 to 4. Image carrier and
A charging means for charging the surface of the image carrier and
An exposure means that exposes the charged image carrier to form an electrostatic latent image,
A developing means for developing a visible image by developing the electrostatic latent image with toner, and
A transfer means for transferring the visible image to a recording medium,
A fixing means for fixing the transferred image transferred to the recording medium, and
An image forming apparatus having a cleaning means for removing toner remaining on the image carrier.
An image forming apparatus, wherein the cleaning means includes the cleaning blade according to any one of claims 1 to 4. A charging process that charges the surface of the image carrier,
An exposure step of exposing the charged image carrier to form an electrostatic latent image,
A developing step of developing the electrostatic latent image with toner to form a visible image,
A transfer step of transferring the visible image to a recording medium,
A fixing step of fixing the transferred image transferred to the recording medium, and
An image forming method including a cleaning step of removing toner remaining on the image carrier by a cleaning means.
An image forming method, wherein the cleaning means includes the cleaning blade according to any one of claims 1 to 4.

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