JP2006162801A - Image forming method and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an improved image forming method by which good cleanability is persistently obtained and high-quality image can be stably maintained when a spherical and small-diameter toner is used, and to provide an image forming apparatus and a cleaning blade for the same. <P>SOLUTION: The image forming method is characterized as follows: the volume average grain size of the toner is ≤7 μm; the circularity of the toner is ≥0.95; the cleaning blade composed of a planar rubber elastic body is used for the cleaning treatment; the cleaning blade has a three-layered structure laminated with the elastic bodies having different elastic properties; assuming the three-layered structure as an abutting layer, an intermediate layer, and an upper layer successively from the side abutting on an image carrying means, the elastic characteristics of the abutting layer and the upper layer are ≥75 to ≤80 degree in rubber hardness and ≤20% in impact resilience at 23°; the elastic characteristics of the intermediate layer are ≤70 degree in rubber hardness and ≥40% to ≤60% in impact resilience at 23°C; and the ratio at which the intermediate layer occupies in the entire layer thickness is ≥10% to ≤30%. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming method and an image forming apparatus, and more particularly, in a cleaning portion in an image forming process, good cleaning characteristics can be obtained over a long period of time with respect to a small particle size or spherical toner, and is stable. The present invention relates to an image forming method and an image forming apparatus capable of obtaining a high-quality image.

  Conventionally, in a transfer type image forming apparatus, a latent image is formed by exposing a document image on, for example, an image carrier (photosensitive member) as a latent image carrier uniformly charged by a charger. A toner is attached to the latent image by a developing device to make a visible image as a toner image. This toner image is transferred to transfer paper or an intermediate transfer medium by a transfer device. The toner remaining on the image bearing means (photoconductor) after transfer is removed from the photoconductor by a cleaning device, and the photoconductor is continuously used repeatedly.

As this cleaning device, a cleaning device using a cleaning blade, a cleaning device using a fur brush roller made of conductive or insulating fibers, a cleaning device using a cleaning roller having polishing ability, a lubricant substance to itself Various types of devices are known, such as a cleaning device using an enclosing cleaning roller, a cleaning device using a magnetic brush roller in which magnetic powder is disposed on the roller surface, and a cleaning device using an aspirator.
The most widely used method is a method using a cleaning blade. It has a simple structure and high toner removability.

  However, in any of the above-described methods, it is difficult to ensure a sufficient cleaning capability for toner or spherical toner having an average particle diameter of 7 μm or less that is being studied for high image quality.

  As a production method for reducing the toner particle size, a polymerization method is effective instead of a conventional pulverization method from the viewpoint of production cost. The small particle size toner produced by the polymerization method has a shape close to a sphere and a sharp particle size distribution, so that good image quality with excellent reproducibility of fine lines and dot reproducibility of digital images can be obtained. have.

  When polymerized toner with a small particle size is used, it is difficult to clean because the shape is close to a true sphere and the particle size is small compared with the toner manufactured by the conventional pulverization method, and it is easy to pass through, black spots, etc. This has the disadvantage of causing poor cleaning. In particular, when a cleaning blade is used, defective cleaning tends to occur when the edge of the blade is worn or chipped by repeated use. In addition, due to the use, the photoreceptor is worn and fine irregularities are formed, and cleaning defects are likely to occur even when the surface roughness increases.

  JP-A-9-50221 (Patent Document 1) and the like attempt to improve environmental stability by defining blade properties. However, in the case of a spherical toner having a small particle diameter, it is not always necessary to provide sufficient cleaning properties. Durability cannot be obtained.

  In JP-A-2002-214989 (Patent Document 2) and JP-A-2002-214990 (Patent Document 3), a cleaning blade having a two-layer structure composed of a base layer and an edge layer bonded with rubber layers having different elastic properties is disclosed. Are known. Patent Document 2 defines the elastic characteristics of two layers for the purpose of improving cleaning properties at low temperatures, and Patent Document 3 for the purpose of suppressing squealing at high temperatures and improving cleaning properties. The toner cleaning properties are not sufficiently considered, and it is difficult to stably obtain good cleaning properties particularly for spherical toners having an average particle diameter of 7 μm or less.

In Japanese Patent Laid-Open No. 2003-29594 (Patent Document 4), as a means for extending the life of the photoconductor and the cleaning blade, amorphous silicon is used as the photoconductor, and the impact resilience of the contact portion of the photoconductor and the photoconductor are affected. There is known a method of using a cleaning blade having a different resilience at a non-contact portion. However, the cleaning properties of small diameter and spherical toner are not taken into consideration, and elastic properties other than rebound resilience are not defined, so that the cleaning properties of small diameter and spherical toner cannot be sufficiently obtained.
At present, there is no image forming method or image forming apparatus that uses a spherical or small-diameter toner to maintain good cleaning characteristics over a long period of time and stably obtain a high-quality image.

Japanese Patent Laid-Open No. 9-50221 JP 2002-214989 A JP 2002-214990 A JP 2003-29594 A

  An object of the present invention is to provide an improved image forming method and an image forming method in which good cleaning properties can be continuously obtained over a long period of time and a high quality image can be stably obtained when a spherical or small diameter toner is used. It is to provide an apparatus and a cleaning blade for them.

That is, the said subject is solved by (1)-(5) of this invention.
(1) “In the image forming method performed by subjecting at least the image carrying means to charging, image exposure, development, transfer, fixing and cleaning, the volume average particle diameter of the toner used for the development is 7 μm or less, The toner has a circularity of 0.95 or more, and the cleaning process is performed using a cleaning blade made of a plate-like rubber elastic body. The cleaning blade is a three-layer structure in which elastic bodies having different elastic properties are laminated. When the contact layer, the intermediate layer, and the upper layer are formed in this order from the side in contact with the image carrying means, the elastic properties of the contact layer and the upper layer are rubber hardness of 75 degrees or more and 80 degrees or less, and 23 ° C. The rebound resilience at 20 ° C. or less, the elastic properties of the intermediate layer are that the rubber hardness is 70 degrees or less, the rebound resilience at 23 ° C. is 40% or more and 60% or less, and the intermediate layer has a total thickness. Image forming method, wherein the mel ratio is 30% or less than 10% ";
(2) “Image forming method characterized in that the ratio of the upper layer to the total thickness in the image forming method described in the item (1) is 50% or more”;
(3) “Image forming method, wherein the toner has a volume average particle size of 5.5 μm or less in the image forming method according to (1) or (2)”;
(4) “The image forming method according to the above-mentioned item (3), wherein the toner has a circularity of 0.98 or more”;
(5) “An image forming apparatus having at least an image carrying means, a charging means, an image exposing means, a developing means, a transferring means, a fixing means, and a cleaning means, wherein the above (1) to (4) An image forming apparatus using any one of the image forming methods described above.

  As a result of examining the cleaning properties of the spherical and small-diameter toners, the blades having high elastic properties, high hardness and low rebound have good cleaning properties in the initial stage. By using a high-hardness and low-repulsion blade, the vibration of the entire blade is small and the nip shape of the contact portion is stable. Therefore, it is considered that the initial cleaning performance of the spherical and small-diameter toner is good. However, since it is hard and has low rubber properties, there is no allowance for blade chipping and the initial cleaning property is not maintained.

While maintaining good cleaning characteristics of high hardness and low repulsion blades, we investigated improvements such as blade chipping. Blade chipping is considered to be caused by collision of protrusions on the surface of the photoreceptor, and a blade that is hard and has low elasticity cannot sufficiently absorb the impact at the time of collision and is likely to cause chipping. A spherical small-diameter toner with a three-layer structure in which a rubber layer with low hardness and high resilience is sandwiched between two high-hardness and low-resilience blades (contact layer, upper layer) Both good cleaning properties and durability such as blade chipping were achieved. The elastic properties of the contact layer and upper layer contribute to stable nip formation in the case of the contact layer, and the upper layer contributes to suppression of vibration of the entire blade. Good cleaning characteristics are obtained, and when the intermediate layer collides with a solid blade, it absorbs the impact and suppresses the chipping of the contact layer with high hardness and low repulsion, contributing to high durability It was found to be.
The inventors have invented an image forming method and an image forming apparatus capable of continuously obtaining good cleaning characteristics over a long period of time even when spherical or small diameter toner is used and stably obtaining a high quality image.

  As will be apparent from the following detailed and specific description, according to the present invention, good cleaning properties can be continuously obtained over a long period of time even when toner having a spherical diameter or a small diameter is used, and high-quality images can be stably obtained. An extremely excellent effect that the obtained image forming method and image forming apparatus can be provided is exhibited.

The cleaning blade of the present invention will be described. The elastic rubber member of the cleaning blade of the present invention is a three-layered blade in which rubber layers having different elastic characteristics are laminated. FIG. 1 is a schematic view of the blade, and the state is in contact with a photoconductor as an image carrying means. A schematic diagram of is shown in FIG. In FIG. 1, (19) is a support member for supporting the rubber blade, (20) is a contact layer, (21) is an intermediate layer, and (22) is an upper layer. Further, t ₁ , t ₂ and t ₃ are the thicknesses of the contact layer (20), the intermediate layer (21) and the upper layer (22), respectively.

  As for the elastic properties of the contact layer (20), the rubber hardness is 75 degrees or more and 80 degrees or less, and the rebound resilience at 23 ° C. is 20% or less.

  When the elastic properties of the contact layer are less than 75 degrees of rubber hardness and when the rebound resilience at 23 ° C. is greater than 20%, the spherical toner slips through, resulting in poor cleaning. By setting the rubber hardness to 75 degrees or more and the rebound resilience at 23 ° C. to 20% or less, the nip portion does not flutter and contributes to stable cleaning. When the hardness is greater than 80 degrees, even when an intermediate layer is provided, the margin for chipping is not sufficient, and the hardness is 80 degrees or less in terms of chipping resistance. The thickness of the contact layer is required to be at least 0.1 mm for the stability and durability of the nip shape.

The rubber hardness was measured using a JIS-K6301 A-type hardness meter, and the rebound resilience was measured using JIS K6255.
The elastic property of the upper layer (22) is that the rubber hardness is not less than 75 degrees and not more than 80 degrees. The impact resilience at 23 ° C. is 20% or less. When the elastic properties of the upper layer are less than 75 degrees of rubber hardness and when the rebound resilience at 23 ° C. is greater than 20%, poor cleaning of the spherical small diameter toner also occurs. By setting the elastic properties of the upper layer to a rubber hardness of 75 degrees or more and a rebound resilience at 23 ° C. of 20% or less, vibration of the blade is suppressed, contributing to stable cleaning. When the hardness is 80 degrees or more, there is no problem in cleaning properties, but there are various inconveniences caused by physical properties different from the contact layer, and the same rubber layer cannot be used, resulting in an increase in cost. Degrees or less are desirable.

  The elastic properties of the intermediate layer (21) are that the rubber hardness is 70 degrees or less, the rebound resilience at 23 ° C. is 40% or more and 60% or less, and the ratio of the intermediate layer to the total layer thickness is 10% or more and 30% or less. . When the rubber hardness is greater than 70 degrees or the impact resilience is less than 40%, the intermediate layer does not have a sufficient margin for the blade chipping of the contact layer, and the intermediate layer does not sufficiently absorb the impact. . On the other hand, if the impact resilience is greater than 60%, the blades hardly vibrate and sufficient cleaning properties cannot be obtained.

  When the ratio of the intermediate layer to the total layer thickness exceeds 30%, the ratio of the layer having high resilience increases, and good cleaning characteristics of spherical and small-diameter toners cannot be obtained. The margin for the blade chipping of the layer is not sufficient, and the shock absorption by the intermediate layer is not sufficient.

  If the upper layer is not provided, and a two-layer structure consisting of only the contact layer and the intermediate layer is used, a sufficient margin for blade chipping cannot be obtained unless the ratio of the layer having high impact resilience is increased. It is impossible to achieve both cleaning performance and blade chipping. A three-layer structure in which an intermediate layer is sandwiched between high hardness and low repulsion blades achieves both cleaning properties and durability.

  More preferably, the layer thickness of the upper layer is 50% or more with respect to the total layer thickness. By making the thickness of the upper layer 50% or more of the total layer thickness, there is an advantage that the margin of the contact layer with respect to the blade chip is further improved.

The material of the cleaning blade is preferably a versatile urethane rubber blade, but in some cases, silicon rubber or the like can be used effectively.
The urethane rubber used in the cleaning blade can be variously changed in hardness and rebound resilience depending on its composition. However, in order to form the cleaning blade by laminating the elastic bodies having different elastic characteristics of the present invention, for example, an image Thermoplastic adhesive with urethane rubber plate of desired thickness blended to have desired hardness and impact resilience for contact layer, typically intermediate layer and upper layer of supporting means (typically photoreceptor) Thus, the laminated body is cut and then cut and further adhered to the blade holder to form a cleaning blade component.

  The toner used has a volume average particle size of 7 μm or less and a circularity of the toner of 0.95 or more. By setting the volume average particle size to 7 μm or less, more preferably to 5.5 μm or less, it is possible to develop faithfully with respect to the latent image and obtain an extremely high-definition image. By setting the circularity to 0.95 or more, more preferably 0.98 or more, developability and transferability are improved, and a high-quality image free from halftone unevenness can be obtained. The volume average particle diameter and circularity were measured using FPIA-2100 manufactured by Sysmex.

  Such a spherical toner of the present invention includes, for example, an organic solvent liquid of a toner material containing at least a resin material for a binder and / or a prepolymer thereof, a colorant, and a release agent in an organic solvent in a fine liquid. Cross-linked and / or elongation reaction obtained by removing the organic solvent and the aqueous medium after being dispersed in the form of droplets, and / or the prepolymer in the droplets during or after the dispersion. Then, it can be produced by removing the organic solvent and the aqueous medium.

Preferably, at least in an organic solvent, a compound having active hydrogen and a polymer having a site capable of reacting with the compound, or a self-polymerizable material having active hydrogen and a site capable of reacting with it in the molecule at the same time The organic solvent and the aqueous system are dissolved or dispersed, preferably in the form of a composition containing them, after reacting with or reacting with the active hydrogen reactive site. The medium can be removed, washed and dried. The circularity of the toner may be adjusted by adjusting the stirring strength during the reaction or by vigorously stirring after drying. As the resin material or / and its prepolymer, various materials can be used, and in particular, a polyester resin or / and a polyester prepolymer can be preferably used.
These are merely examples, and the spherical toner may of course be manufactured by a method other than such a manufacturing method.

Subsequently, an image forming method and an image forming apparatus of the present invention will be described.
FIG. 3 is a schematic view showing an image forming method and an image forming apparatus of the present invention.
The photosensitive member (6) as a typical example of the image carrying means has a drum shape, but may be a sheet shape or an endless belt shape.
Around the photoreceptor (6), a pre-transfer charger (7), a transfer charger, a separation charger, and a pre-cleaning charger (8) are arranged as necessary, and corotron, scorotron, solid state charger (solid state Charger) and known means such as a charging roller are arranged.

The charging member (9) may be in contact with the image carrying means (for example, typically a photoconductor). However, by arranging a suitable gap (about 10 to 200 μm) between them, Both wear amounts can be reduced and toner filming on the charging member can be suppressed, which can be preferably used.
The voltage applied to the charging member (9) is effective when the AC component is superimposed on the DC component in order to stabilize charging and suppress charging unevenness.

However, it is known that when the AC component is superimposed, charging is generally stabilized, but the surface layer of the photoconductor used during the process is more easily worn than when only the DC component is applied. Also in this case, the image bearing means (photoreceptor) of the present invention can maintain good characteristics without any problem because of its high wear resistance.
As the transfer means, the above charger can generally be used, but those using a transfer belt (10) as shown in FIG. 3 are effective.
Further, light sources such as the image exposure unit (11) and the charge removal lamp (12) include fluorescent lamps, tungsten lamps, halogen lamps, mercury lamps, sodium lamps, light emitting diodes (LEDs), semiconductor lasers (LD), electroluminescence (EL). ) And other luminescent materials can be used.

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.
These light sources are used not only for the process shown in FIG. 3 but also for a transfer process using light irradiation, a static elimination process, a cleaning process, a pre-exposure process, etc., and irradiate the photoreceptor (6) with light.

  The toner developed on the photosensitive member (6) by the developing unit (13) is transferred to the transfer paper (14), but not all is transferred, and the toner remaining on the photosensitive member (6) is also transferred. The toner is removed from the photoreceptor (6) by the fur brush (15) and the cleaning blade (16).

Although cleaning may be performed only with a cleaning blade, a cleaning brush such as a fur brush is often used in combination.
FIG. 2 shows the contact state of the cleaning blade of the present invention with the photosensitive member. In the figure, the photoconductor moves from right to left, and the toner remaining on the photoconductor is scraped off by a cleaning blade that abuts in the counter direction. Here, the contact value between the cleaning blade and the photosensitive member varies depending on the elastic characteristics of the cleaning blade. However, the amount of biting into the photosensitive member is usually 1 to 2 mm, and the cleaning blade cut surface (urethane rubber). The angle between the plate cutting surface) and the surface of the photoreceptor is set to 70 to 85 degrees. The larger the bite amount, the greater the contact pressure with the photoconductor, which is advantageous for cleaning.However, if excessive, the wear angle of the photoconductor is increased or the blade deflection is increased to displace the contact angle. I will let you. The contact angle between the cleaning blade cut surface and the surface of the photosensitive member is preferably set so as not to cause the cleaning blade edge portion to be turned over, especially for changes in the elastic properties of urethane rubber at high temperatures. A setting with a margin is required.

When the electrophotographic photosensitive member is positively (negatively) charged and image exposure is performed, a positive (negative) electrostatic latent image is formed on the surface of the photosensitive member.
If this is developed with negative (positive) polarity toner (electrodetection fine particles), a positive image can be obtained, and if developed with positive (negative) polarity toner, a negative image can be obtained.
A known method is applied to the developing unit, and a known method is also used as the charge eliminating unit.
(17) is a registration roller, and (18) is a separation claw.

The present invention is an image forming method and an image forming apparatus using an image bearing means (typically, an electrophotographic photosensitive member) as such an image forming means.
The image forming unit may be fixedly incorporated in a copying apparatus, a facsimile machine, or a printer, but may be incorporated in these apparatuses and made detachable in the form of a process cartridge.
Here, the process cartridge is an apparatus (part) that includes an image carrier means such as a photosensitive member and a cleaning means, and further includes at least one of a charging means, an exposure means, a developing means, and a transfer means. It is.

(Example 1)
[Evaluation blade]
As a urethane rubber blade for evaluation, three urethane rubber sheets were bonded with a thermoplastic adhesive to produce a three-layer urethane blade. As for the elastic properties of each urethane rubber sheet, the rubber properties of the contact layer and the upper layer are 76 ° hardness and 14% rebound resilience at 23 ° C., and the rubber property of the intermediate layer is 68 ° hardness and 50% rebound resilience at 23 ° C. It is. The thickness of each layer is 0.7 mm for the contact layer t ₁ , 0.5 mm for the intermediate layer t ₂ , and 0.8 mm for the upper layer t ₃ .

[Toner used]
A toner having a volume average particle diameter of 6.5 μm and a circularity of 0.95 prepared by a polymerization method was used. This toner was mixed with a carrier in which a core of Cu—Zn ferrite was coated with silicone, in a ratio of 7 parts by weight to 93 parts by weight to prepare a developer.

[Evaluation methods]
The Ricoh IPSIO-COLOR 8000 was replaced with the above blade and toner, and 100K images with a printing rate of 6% were run and evaluated. Initially, at 10K, 50K, and 100K sheets, cleaning property, image quality evaluation, cleaning blade wear and chipping were evaluated.

[Cleaning property evaluation]
The rank of the cleaning property was evaluated and evaluated in five stages. 5 is the best and 1 is poor. The allowable level that can withstand actual use is 3 or more.

[Image quality evaluation]
As the image quality evaluation, half-tone unevenness, resolving power, sharpness, etc. were comprehensively evaluated, and a 5-level rank evaluation was performed. 5 is the best and 1 is bad.

[Evaluation of chipping of cleaning blade]
The cleaning blade was removed, and observation was performed with a laser microscope (Keyence VK-8500). Blade chipping is evaluated by rank, 5 is the best, and 1 is extremely deteriorated.

(Example 2)
The evaluation cleaning blade of the cleaning blade of Example 1 is the same as that of Example 1, except that the rubber layers of the contact layer and the upper layer are changed to those having an elastic property of rubber hardness of 79 degrees and a rebound resilience of 18% at 23 ° C. And exactly the same.

(Comparative Example 1)
The evaluation cleaning blade was a single-layer blade having a thickness of 2 mm using rubber having the same elastic characteristics as the contact layer of the cleaning blade of Example 1. Other than that, evaluation was performed in the same manner as in Example 1.
At the end of 50K running, the cleaning performance was poor and the blades were severely chipped.

(Comparative Example 2)
The evaluation cleaning blade was the same as in Example 1 except that the rubber layer of the intermediate layer in the cleaning blade of Example 1 was changed to one having an elastic property of 72 degrees rubber hardness and a rebound resilience of 35% at 23 ° C. It was.

(Comparative Example 3)
Evaluation cleaning blade changes, the layer thickness _{t 1} is 0.4mm contact layer in the cleaning blade of Example 1, the thickness _{t 2} is 0.8mm intermediate layer, the thickness t ₃ of the upper layer 0.8mm Evaluation was performed in the same manner as in Example 1 except that.
At the end of 50K running, the cleaning performance was poor, so the test was stopped at 50K.

(Comparative Example 4)
The evaluation cleaning blade in the cleaning blade of Example 1 has a contact layer thickness t ₁ of 0.8 mm, an intermediate layer thickness t ₂ of 0.1 mm, and an upper layer thickness t ₃ of 1.1 mm. Evaluation was performed in the same manner as in Example 1 except that the change was made.

(Comparative Example 5)
The evaluation cleaning blade is exactly the same as in the cleaning blade of Example 1, except that the contact layer and the upper layer are made of rubber having elastic properties of rubber hardness of 70 ° and rebound resilience at 27 ° C. of 27%. Evaluation was performed in the same manner.

(Example 3)
Evaluation cleaning blade, the cleaning blade of Example 1, the thickness of each layer thickness _{t 1} of the abutting layer is 0.5 mm, thickness t of the intermediate layer is 0.3 mm, the thickness _{t 3} of the upper layer Evaluation was performed in the same manner as in Example 1 except that the thickness was changed to 1.2 mm.

Example 4
Evaluation was performed in exactly the same manner as in Example 3 except that a toner produced by a polymerization method having a volume average particle size of 5.4 μm or less and a circularity of 0.95 was used.

(Example 5)
Evaluation was performed in exactly the same manner as in Example 3 except that a toner prepared by a polymerization method having a volume average particle size of 5.4 μm or less and a circularity of 0.98 was used.

(Comparative Example 6)
The evaluation cleaning blade is a two-layer blade, the contact layer has the same elastic characteristics as the contact layer of Example 1, the contact layer thickness t1 is 0.3 mm, and the layer on the non-contact surface side is implemented. Except for using a blade having the same elastic characteristics as the intermediate layer of Example 1 and a layer thickness t2 of 1.7 mm, it was evaluated in the same manner as in Example 1 and was poorly cleaned from the beginning. However, the experiment was stopped because the image was very bad.

(Comparative Example 7)
The evaluation cleaning blade is a two-layer blade, the contact layer has the same elastic characteristics as the contact layer of Example 1, the contact layer thickness t1 is 1.3 mm, and the layer on the non-contact surface side is implemented. Except for using a blade having the same elastic characteristics as the intermediate layer of Example 1 and having a layer thickness t2 of 0.7 mm, it was evaluated in exactly the same manner as in Example 1. At the end of 50K, the cleaning property was extremely poor. The experiment was stopped because the image was poor.
Table 1 summarizes the test conditions, and Table 2 summarizes the evaluation results.

It is a figure showing the cleaning blade of the 3 layer structure in this invention. FIG. 3 is a diagram illustrating a state in contact with a photoconductor as an image carrying unit in the present invention. 1 is a diagram illustrating an image forming method and an image forming apparatus according to the present invention.

Explanation of symbols

6 Photoconductor 7 Charger before transfer 8 Charger before cleaning 9 Charging member 10 Transfer belt 11 Image exposure unit 12 Static elimination lamp 13 Development unit 14 Transfer paper 15 Fur brush 16 Cleaning blade 17 Registration roller 18 Separation claw 19 Support member 20 Contact layer 21 Intermediate layer 22 Upper layer

Claims (5)

  In an image forming method in which at least image bearing means is charged, image exposed, developed, transferred, fixed and cleaned, the toner used in the developing process has a volume average particle size of 7 μm or less, and the toner has a circular shape. The degree of cleaning is 0.95 or more, and the cleaning process is performed using a cleaning blade made of a plate-like rubber elastic body, and the cleaning blade has a three-layer structure in which elastic bodies having different elastic properties are laminated, When the contact layer, the intermediate layer, and the upper layer are formed in this order from the side in contact with the image bearing means, the elastic properties of the contact layer and the upper layer are that the rubber hardness is 75 degrees or more and 80 degrees or less and the rebound resilience at 23 ° C. The elastic property of the intermediate layer is that the rubber hardness is 70 degrees or less, the rebound resilience at 23 ° C. is 40% or more and 60% or less, and the ratio of the intermediate layer to the total layer thickness Image forming method, wherein the but 30% or less than 10%.   2. The image forming method according to claim 1, wherein the ratio of the upper layer to the total thickness is 50% or more.   3. The image forming method according to claim 1, wherein the toner has a volume average particle size of 5.5 μm or less.   The image forming method according to claim 3, wherein the toner has a circularity of 0.98 or more. 5. An image forming apparatus having at least an image carrying means having a charging means, an image exposure means, a developing means, a transfer means, a fixing means, and a cleaning means, wherein the image forming method according to claim 1 is used. An image forming apparatus.

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