JP2016081026A - Blade member and image forming apparatus including the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a blade member that can suppress the generation of an abnormal noise caused by sliding between a contact target member and a tip ridge part and suppress loss of elasticity occurring over time, and an image forming apparatus including the same.SOLUTION: There is provided a blade member 5 that brings an edge part 61 that is a tip ridge part of an elastic blade into contact with the surface of a contact target member, where the elastic blade has a lamination structure including an edge layer 6 having an edge part and at least one or more layers 7 having the edge layer laminated thereon, and the layers other than the edge layer have an elastic power larger than the elastic power of the edge layer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a blade member and an image forming apparatus including the blade member.

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus, unnecessary transfer residual toner adhering to a surface after transferring a toner image to a transfer paper or an intermediate transfer body is removed as a cleaning unit. Has been removed by.
As a cleaning member of this cleaning device, one that uses a cleaning blade as a blade member is well known because it can generally be simplified in configuration and has excellent cleaning performance.

  Patent Document 1 describes a cleaning blade composed of an elastic blade made of urethane rubber. The base end of the cleaning blade is supported by a support member, the tip edge line portion is pressed against the surface of the image carrier, and the toner remaining on the image carrier is damped and scraped off and removed.

The cleaning blade has a high hardness at the edge to scrape off the sticking material such as toner external additive that adheres to the surface of the photoconductor, and the abnormal image (filled image) caused by the toner external additive sticking on the photoconductor. There is an effect of suppressing the ming). However, the urethane rubber used for the material of the cleaning blade generally tends to have a lower elastic power as the hardness increases.
When a material having a low elastic power is used for the cleaning blade having a single layer structure, the following problems occur. That is, in the deformation of the cleaning blade that occurs when a bending or compressive force is applied, the plastic deformation ratio is larger than the elastic deformation ratio, and the cleaning blade is permanently deformed into a bent shape. Will occur. Due to the settling of the cleaning blade, there is a problem that the linear pressure of the cleaning blade against the contacted member is lowered and the contact posture is changed, so that the cleaning function is deteriorated.

In addition, if a material having a high elastic work rate is used for the cleaning blade in order to suppress settling over time, the tip ridge line portion (edge portion) of the cleaning blade having an abutting portion that abuts against the abutting member Minute vibration is generated by sliding with the contact member. The frequency at the edge portion increases when it coincides with the natural frequency of the cleaning blade, which may cause abnormal noise.
The elastic power is one of the indexes indicating the ease of return from deformation when a force is applied to the rubber and the deformation occurs. The higher the elastic power, the faster the return from deformation. For this reason, the cleaning blade having a high elastic power has a high vibration speed at the edge portion, and is likely to generate abnormal noise due to vibration.

  The present invention has been made in view of the above background, and an object of the present invention is to provide a blade member capable of suppressing generation of abnormal noise due to sliding between a contacted member and a tip ridge line portion, and suppressing settling over time. And an image forming apparatus including the same.

  In order to achieve the above object, the present invention provides a blade member that abuts an edge portion, which is a tip ridge line portion of an elastic blade, on a surface of a contacted member, wherein the elastic blade includes an edge layer having the edge portion. A blade having at least one layer in which the edge layer is laminated, and the elastic power of the layers other than the edge layer is larger than the elastic power of the edge layer Element.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the abnormal noise by sliding with a to-be-contacted member and a front-end | tip ridgeline part can be suppressed, and the stickiness which arises with time can be suppressed.

Sectional drawing of the cleaning blade which concerns on this embodiment. Explanatory drawing about the vibration of the edge part of the conventional cleaning blade. The graph which shows the integrated stress Wplast when pushing in a Vickers indenter, and the integrated stress at the time of unloading a test load Welast. Explanatory drawing about the measuring method of the elastic power of the edge part of a cleaning blade, and Martens hardness. 1 is a schematic configuration diagram of a printer according to an embodiment. FIG. 2 is a schematic configuration diagram illustrating an example of a process cartridge provided in the printer. FIG. 3 is a schematic configuration diagram of another example of a process cartridge provided in the printer. FIG. 6 is a schematic configuration diagram of still another example of a process cartridge included in the printer. FIG. 3 is an explanatory diagram of a layer configuration of a photoreceptor in the present embodiment. (A) is sectional drawing of the photoreceptor which provided the photosensitive layer on the electroconductive support body. (B) is a figure which shows the example which further provided the surface layer in the structure of (a). (C) is a figure which shows the example which made the photosensitive layer 2 layer structure in the structure of (b). (D) is a figure which shows the example which provided the undercoat layer in the structure of (c). Explanatory drawing for demonstrating the measuring method of the circularity of a toner. Explanatory drawing about abrasion of the edge part of the conventional cleaning blade.

Hereinafter, an embodiment of a blade member to which the present invention is applied will be described.
FIG. 1 is a cross-sectional view of a cleaning blade according to the present embodiment.
As shown in FIG. 1, a cleaning blade 5 as a blade member of the present embodiment has a base end of the cleaning blade 5 supported by a support member 3 and a tip of an elastic blade on the surface of a contacted member (not shown). A ridge line part (edge part) 61 is brought into contact therewith. The cleaning blade 5 has a laminated structure composed of two layers of an edge layer 6 having an edge portion 61 and a backup layer 7 on which the edge layer 6 is laminated.

  The edge layer 6 and the backup layer are composed of elastic members having different elastic powers. The backup layer 7 uses a urethane rubber material having a higher elastic power than the edge layer 6, and the backup layer 7 is thicker than the edge layer 6. .

A conventional cleaning blade has a single-layer structure made of a low-hardness polyurethane rubber or the like, and has an elastic power near the edge of 90% and a Martens hardness of about 0.7 [N / mm ² ]. When a material having a low elastic work rate is used for the cleaning blade, the plastic deformation rate is larger than the elastic deformation rate in the deformation that occurs when a force is applied to the cleaning blade. When the rate of plastic deformation is larger than the rate of elastic deformation, the cleaning blade is crushed and the cleaning function is lowered due to the rot.

  The cleaning blade 5 of the present embodiment has a laminated structure including an edge layer 6 and a backup layer 7, and the elastic power of the backup layer 7 is higher than the elastic power of the edge layer 6. As a result, the amount of plastic deformation of the backup layer 7 that occurs when a bending or compressive force is applied to the cleaning blade 5 is smaller than the amount of plastic deformation of the edge layer 6. Further, in the cleaning blade 5 of the present embodiment, the degree of influence on the deformation of the entire cleaning blade per unit thickness is the same for the edge layer 6 and the backup layer 7, and the backup layer 7 is larger than the thickness of the edge layer 6. The thickness of is increased. For this reason, the deformation of the backup layer 7 is dominant as the deformation of the entire cleaning blade. Therefore, since the amount of plastic deformation of the backup layer 7 is smaller than the amount of plastic deformation of the edge layer 6, it is possible to suppress the settling of the entire cleaning blade 5.

  In addition, when a material having a high elastic work rate is used for a conventional cleaning blade having a single-layer structure, minute vibrations are generated at the edge of the cleaning blade due to sliding between the contacted member and the cleaning blade. When the vibration of the edge portion coincides with the natural frequency of the cleaning blade, it may increase and generate abnormal noise.

  In the cleaning blade 5 of the present embodiment, the elastic power of the edge layer 6 is lower than the elastic power of the backup layer 7. As a result, when the vibration of the edge layer 6 having the edge portion 61 that is in direct contact with the contacted member tends to increase in accordance with the natural frequency of the cleaning blade 5, the backup layer 7 exhibits a vibration isolation function. Specifically, since the backup layer 7 is a material that does not come into contact with the contacted member and has a lower elastic work rate than the edge layer 6, the backup layer 7 absorbs the vibration of the edge layer 6 and has a vibration-proof function. Demonstrate. Accordingly, it is possible to prevent the generation of abnormal noise due to minute vibration of the edge portion 61 due to sliding with the contacted member.

FIG. 2 is an explanatory view of the vibration of the edge portion of the conventional cleaning blade.
As shown in FIG. 2A, the vibration of the edge portion 261 that occurs when the edge portion 261 of the conventional cleaning blade 105 comes into contact with the surface of the abutting member 110 whose surface moves in the direction of the arrow in the drawing will be described. To do.
The elastic power is one of indices indicating the ease of return from deformation when a force is applied to the rubber and the deformation occurs. When the elastic power of the cleaning blade 105 is high, the return speed from the deformation due to the contact with the contacted member 110 in the edge portion 261 increases, and the edge portion of the cleaning blade 105 as shown in FIG. The vibration of 261 becomes faster. Therefore, the vibration of the edge portion 261 is likely to coincide with the natural frequency of the cleaning blade 105, so that abnormal noise due to this vibration is likely to occur.

  In the cleaning blade 5 of this embodiment, the elastic power of the edge layer 6 is lower than the elastic power of the backup layer 7. As a result, the backup layer 7 absorbs the vibration due to the deformation of the edge layer 6, and the frequency of the edge layer 6 and the natural frequency of the cleaning blade 5 do not easily match. Therefore, it is possible to make it difficult to generate vibrations that accompany the return from the deformation of the edge portion.

As described above, when a member having a low elastic power is used in a conventional cleaning blade having a single layer structure, the amount of plastic deformation generated when bending or compression force is applied to the cleaning blade is large. Further, when a member having a high elastic power is used for the cleaning blade, the settling is reduced, but the blade edge portion vibrates and the blade squeals. That is, with the conventional single-layer cleaning blade, it has been difficult to achieve both suppression of blade sag and blade noise. In addition, even in a blade having a laminated structure, a regulation regarding the relationship between the elastic power of the edge layer and the backup layer is required for the long life and high reliability of the cleaning blade.
As in the present embodiment, the cleaning blade 5 having a laminated structure is configured such that the elastic power of the backup layer 7 is larger than the elastic power of the edge layer 6, so that the contacted member, the tip ridge line portion, It is possible to suppress the generation of abnormal noise due to sliding, and to suppress the settling over time.

The difference in elastic power between the edge layer 6 and the backup layer 7 is preferably 5% or more and 50% or less.
If the difference in elastic power between the edge layer 6 and the backup layer 7 is less than 5%, there is no difference in elastic power between the edge layer 6 and the backup layer 7, so that the elastic power of the cleaning blade 5 is lower. Stickiness tends to occur, and the higher the elastic power of the cleaning blade 5, the more likely it is that abnormal noise is generated.
In addition, when the difference in elastic power between the edge layer 6 and the backup layer 7 exceeds 50%, the elastic power of the edge layer 6 inevitably becomes a low value, which is caused by plastic deformation of the edge portion 61. The cleaning function tends to deteriorate.

  In the above description, the laminated structure of the cleaning blade 5 has been described as a two-layer structure of the edge layer 6 and the backup layer 7, but the configuration for obtaining the effects of the present invention is not limited to this. For example, the present invention can also be applied when the backup layer 7 has a plurality of layer structures.

  In the above description, the urethane rubber material having a higher elastic work rate than that of the edge layer 6 is used for the backup layer 7. However, the configuration for obtaining the effects of the present invention is not limited to this. Absent. As long as the elastic power of the backup layer 7 is higher than that of the edge layer 6, the same effect can be obtained even when a material other than the urethane rubber material is used.

  In addition, when the backup layer is thick and the edge layer is thin, the backup layer with a high elastic power is dominant over the deformation of the entire blade, and the backup layer with a high elastic power (not easily plastically deformed) exhibits a deterring effect. In addition, settling can be prevented. If the edge layer is too thin, the backup layer is exposed as soon as the edge layer wears due to sliding with the member to be cleaned, and the backup layer with a high elastic work rate comes into contact with the member to be cleaned. Resulting in. Therefore, the thickness of the edge layer is preferably set to such a thickness that the backup layer is not exposed even if the edge layer is worn.

Next, verification experiments conducted by the applicant will be described.
[Verification experiment 1]
The following first verification experiment (hereinafter referred to as verification experiment 1) and second verification experiment (hereinafter referred to as verification experiment 2) are comparatively examined by changing the layer configuration, elastic power, and Martens hardness of the cleaning blade. It is what went.

[Elastic power]
The elastic power of the edge portion of the cleaning blade was measured using HM-2000 manufactured by Fischer Instruments. Specifically, at a position of 20 [μm] from the edge ridge line portion, it is pressed for 10 seconds with a force of 1.0 [mN] Vickers indenter, held for 5 seconds, and measured for 10 seconds. The elastic power is a characteristic value obtained as follows. If the cumulative stress when pushing in the Vickers indenter is Wplast, and the cumulative stress when unloading the test load is Welast, the elastic power is a characteristic value defined by the formula Welast / Wplast × 100% (see FIG. 3). . The higher the elastic work rate, the smaller the proportion of plastic work from when force is applied to the material to generate strain until unloading. That is, the ratio of plastic deformation that occurs when rubber is deformed by force is small.

FIG. 4 is an explanatory diagram of a method for measuring the elastic power and Martens hardness of the edge layer of the cleaning blade.
As shown in FIG. 4, the cleaning blade 5 includes an edge portion 61 of the cleaning blade 5, a blade facing surface 62 that faces the contacted member, and a blade tip that includes the edge portion 61 and is adjacent to the blade facing surface. A surface 63 is provided.
In the cleaning blade 5 having a two-layer structure, when the thickness of the edge layer 6 is very small as compared with the thickness of the backup layer 7, the measurement is performed by measuring the elastic power of the edge layer 6 from the blade facing surface 62 side. The value may be affected by the elastic power of the backup layer 7.
For example, in the measurement of the elastic power of the edge layer 6, when the elastic power of the edge layer 6 is lower than the elastic power of the backup layer 7, the edge layer 6 is affected by the elastic power of the backup layer 7. The elastic power of 6 is measured higher than the result of measuring the elastic power of the material used for the edge layer 6 alone.

As a result of intensive studies by the present applicant, the thickness of the edge layer 6 is very small compared to the thickness of the backup layer 7 by measuring the elastic power of the edge layer 6 using the following method. However, it was found that the elastic power of the edge layer 6 can be accurately measured.
First, the elastic power of the edge layer 6 measured from the blade facing surface 62 side of the cleaning blade 5 is A, the elastic power of the edge layer 6 measured from the blade tip surface 63 side of the cleaning blade 5 is B, and the cleaning blade 5 Let C be the elastic power of the backup layer 7 measured from the blade tip surface 63 side. Then, the difference between A and C and the difference between B and C are respectively calculated, and the value of the elastic power of the edge layer 6 having the larger absolute value of the difference is set as the elastic power of the edge layer 6. That is, when the absolute value of the difference between B and C is larger than the difference between A and C, the value of A is set. When the absolute value of the difference between A and C is larger than the difference between B and C, B is set. Is the elastic power of the edge layer 6.
In this verification experiment, the elastic power values selected using this method are shown in Table 1.

  Next, the configuration and evaluation items of the image forming apparatus for which the verification experiment was performed will be described.

(Presence or absence of poor cleaning in low temperature and low humidity environment)
Using a Ricoh MPC3503 machine as an experimental machine, the cleaning blade of the process cartridge having the configuration shown in FIG. 6 is changed to the cleaning blade of the conditions of Examples 1 to 14 and Comparative Examples 1 to 10 in Table 1, and measurement is performed. It was.
The test machine was allowed to stand for 24 hours in a low-temperature and low-humidity environment (10 ° C. and 15%) where cleaning failure tends to occur, and 8000 images were continuously output in an environment of 10 ° C. and 15%. The output image was a solid image on A4 recording paper so as to maximize toner input to the photoreceptor. Then, it was visually observed whether or not a cleaning failure was apparent on the paper, and evaluated as follows.
○: Good cleaning property. After passing 8,000 sheets, there is no problem in actual use because no cleaning defect appears on the paper.
X: Cleaning failure occurred. After passing 8,000 sheets, the cleaning defect is alive on the paper, and there is a problem as an abnormal image in actual use.

(Generation of abnormal noise)
Using a Ricoh MPC3503 machine as an experimental machine, the process cartridge cleaning blade having the configuration shown in FIG. 6 was changed to the blade members having the conditions of Examples 1 to 14 and Comparative Examples 1 to 10 in Table 1, and measurement was performed. It was.
Using the above-mentioned experimental machine, 4000 sheets were continuously passed under a normal temperature room environment (23 ° C., 50%), and an image with an image area ratio of 5% on an A4 recording paper (an average image when using the product) Area ratio) was output. Then, the presence or absence of abnormal noise was confirmed by the ears of people passing through the paper, and the following determination was made.
○: No abnormal noise occurred. No noticeable noise was generated between 4000 sheets.
X: Abnormal noise occurs. Significant noise was generated between 4000 sheets.

(Blade Hetari)
Using a Ricoh MPC3503 machine as an experimental machine, the process cartridge cleaning blade having the configuration shown in FIG. 6 was changed to the blade members having the conditions of Examples 1 to 14 and Comparative Examples 1 to 10 in Table 1, and measurement was performed. It was.
Using the experimental device, the cleaning blade is left in contact with the image carrier for 7 days (168 hours) in a normal room environment (23 ° C. and 50%), before and after contact. The blade edge contact pressure is measured. A change in contact pressure over time, which is caused by bringing the cleaning blade into contact with the image carrier and holding the blade in a state where pressure is applied thereto, is compared. The contact pressure when contacting the image carrier is 20 [g / cm].
The influence on the cleaning property due to the settling was performed under a high charging current condition in which cleaning failure is likely to occur, and was evaluated as follows.
◯: Less than 4.0 [g / cm] (20% of the set linear pressure) linear pressure drop. No effect on cleaning performance.
X: The amount of linear pressure reduction is 4.0 [g / cm] (20% of the set linear pressure) or more. There is an effect on cleaning performance.

Table 1 shows the results of the verification experiments of Examples and Comparative Examples in this verification experiment.

Example 1
As the cleaning blade of Example 1, a cleaning blade having a two-layer structure of an edge layer and a backup layer as shown in FIG. 1 was used. The thickness of the edge layer is 0.5 [mm], and the thickness of the backup layer is 1.3 [mm]. The elastic power of the edge layer is 82% and the elastic power of the backup layer is 91%. The elastic power of the backup layer is higher than that of the edge layer.

In Example 1, the linear pressure decrease amount after leaving the cleaning blade in contact with the image carrier, which is a member to be contacted, for 168 hours was 2.3 [g / cm]. This is a value smaller than the linear pressure reduction amount 4.0 [g / cm] (20% of the set linear pressure) at which the cleaning failure occurs due to the linear pressure reduction in the MPC3503 machine, and the linear pressure is such that the cleaning performance is affected. It was not a decline.
The reason why the deterioration of the cleaning property due to settling can be suppressed is considered as follows.

  That is, in Example 1, by making the elastic power of the backup layer higher than that of the edge layer, the amount of plastic deformation of the backup layer that occurs when bending or compressive force is applied to the blade is Less than the amount of plastic deformation of the layer. In the cleaning blade of Example 1, the degree of influence on the deformation of the entire cleaning blade per unit thickness is equal between the edge layer and the backup layer, and the backup layer is thicker than the edge layer. As a result, the deformation of the backup layer is dominant as the deformation of the entire cleaning blade. Therefore, it is considered that the amount of plastic deformation of the backup layer is smaller than the amount of plastic deformation of the edge layer, thereby suppressing the settling of the entire cleaning blade.

Further, in Example 1, the elastic power of the edge layer is made lower than the elastic power of the backup layer, so that the vibration of the edge layer having the edge portion that is in direct contact with the photosensitive member becomes the natural frequency of the cleaning blade. When trying to increase in size, the backup layer that does not come into contact with the photoreceptor exhibits a vibration-proof function. Therefore, it was possible to prevent the generation of abnormal noise due to minute vibration of the edge portion due to sliding with the contacted member.
Furthermore, in Example 1, by making the elastic power of the edge layer lower than the elastic power of the backup layer, the backup layer absorbs the vibration due to the deformation of the edge layer, and the frequency of the edge layer and the cleaning blade It becomes difficult to match the natural frequency. Therefore, it is possible to make it difficult to generate vibration that occurs with the return from the deformation of the edge portion.

(Examples 2 to 14)
As the cleaning blades of Examples 2 to 14, cleaning blades in which the elastic power of the edge layer and the elastic power of the backup layer were changed to the values shown in Table 1 from the configuration of Example 1 were used.
In the cleaning blades of Examples 2 to 14, the magnitude relationship between the elastic powers of the edge layer and the backup layer is the same as that of Example 1, and the generation of noise due to the sliding between the contacted member and the edge portion is suppressed. It was possible to suppress the settling over time. The reason why such an evaluation is obtained is the same as that in the first embodiment, and thus the description thereof is omitted.

(Comparative Example 1)
The cleaning blade of Comparative Example 1 was not a laminated structure like the cleaning blades of Examples 1 to 14, but a single-layered cleaning blade. The elastic power is 92%, which is larger than the elastic power of the edge layer of the cleaning blades of Examples 1 to 14.
Since the cleaning blade with a single layer structure uses a material with a high elastic work rate, sliding with the photosensitive member generates minute vibrations at the edge of the cleaning blade, and the frequency at this edge is the cleaning blade. An abnormal noise was generated by matching the natural frequency of.
Furthermore, since the value of the elastic power is large, the vibration speed of the blade edge portion is increased, and abnormal noise due to vibration is easily generated.

(Comparative Example 2)
The cleaning blade of Comparative Example 2 was not a laminated structure like the cleaning blades of Examples 1 to 14, but a single-layered cleaning blade. Further, as a result of measuring the change in linear pressure after leaving the cleaning blade in contact with the image carrier for 168 hours, the amount of decrease in linear pressure was 5.9 [g / cm]. This is a value larger than the linear pressure drop 4.0 [g / cm] (20% of the set linear pressure) at which the cleaning failure occurs due to the decrease in the linear pressure in the MPC3503 machine, and the cleaning failure occurs due to the decrease in the blade linear pressure. did. The elastic power of the cleaning blade of Comparative Example 2 is 38%, which is lower than the elastic power of the cleaning blades of Examples 1-14.
The cleaning blade of Comparative Example 2 uses a material having a low elastic power for the cleaning blade having a single layer structure. For this reason, in the deformation of the cleaning blade that occurs when bending or compressive force is applied, the rate of plastic deformation is greater than the rate of elastic deformation, and the occurrence of settling has an effect on cleaning properties. It is thought that it has been.

(Comparative Example 3)
As the cleaning blade of Comparative Example 3, a cleaning blade having a two-layer structure of an edge layer and a backup layer as shown in FIG. 1 was used. The thickness of the edge layer is 0.5 [mm], and the thickness of the backup layer is 1.3 [mm]. Further, the elastic power of the edge layer is 92% and the elastic power of the backup layer is 68%. Unlike the magnitude of the elastic power of the edge layer and the backup layer in Examples 1 to 14, the edge layer has The elastic power of the backup layer is lower than the elastic power.
As a result of measuring the change in linear pressure after leaving the cleaning blade in contact with the image carrier for 168 hours, the amount of decrease in linear pressure was 5.2 [g / cm]. This is a value larger than the linear pressure drop 4.0 [g / cm] (20% of the set linear pressure) at which the cleaning failure occurs due to the decrease in the linear pressure in the MPC3503 machine, and the cleaning failure occurs due to the decrease in the blade linear pressure. did.

  In the cleaning blade of Comparative Example 3, the elastic power of the backup layer is lower than that of the edge layer. In the cleaning blade of Comparative Example 3, the degree of influence on the deformation of the entire cleaning blade per unit thickness is the same between the edge layer and the backup layer, and the thickness of the backup layer 7 is larger than the thickness of the edge layer. It is thick. For this reason, the deformation of the backup layer is dominant as the deformation of the entire cleaning blade. Therefore, the amount of plastic deformation of the backup layer is larger than the amount of plastic deformation of the edge layer, so that the entire cleaning blade is set and the cleaning failure occurs due to a decrease in the blade linear pressure.

In addition, the cleaning blade of Comparative Example 3 uses a material having a higher elastic power for the edge layer than the elastic power of the backup layer. For this reason, when minute vibrations are generated at the edge of the cleaning blade due to sliding with the photoconductor, the elastic power of the backup layer is lower than the elastic modulus of the edge layer. Does not demonstrate. Therefore, the frequency of the edge layer easily matches the natural frequency of the cleaning blade, and abnormal noise due to vibration was generated.
Further, since the elastic power of the edge layer is higher than the elastic power of the backup layer, the recovery speed from the deformation due to the contact of the edge portion with the photosensitive member is fast, and the vibration of the edge portion is accelerated. As a result, the vibration of the edge portion is likely to coincide with the natural frequency of the cleaning blade, and the vibration generated with the return from the deformation of the edge portion is likely to occur.

(Comparative Examples 4-6)
As the cleaning blades of Comparative Examples 4 to 6, cleaning blades in which only the values of the elastic power of the edge layer / backup layer were changed to the values shown in Table 1 from the configuration of Comparative Example 3 were used.
Also, the cleaning blades of Comparative Examples 4 to 6 are different in the elastic power ratio between the edge layer and the backup layer in Examples 1 to 14, and the elastic power of the backup layer is lower than that of the edge layer. ing. For this reason, in the cleaning blades of Comparative Examples 4 to 6, cleaning failure occurred due to a decrease in blade linear pressure, and abnormal noise due to sliding between the contacted member and the edge portion occurred. The reason why such an evaluation is obtained is the same as in Comparative Example 3, and thus the description thereof is omitted.

(Comparative Examples 7 and 8)
In the cleaning blades of Comparative Examples 7 and 8, as with the cleaning blades of Examples 1 to 14, the elastic power of the backup layer is higher than the elastic power of the edge layer. For this reason, the effect similar to Example 1 was able to be acquired about suppression of the settling of a cleaning blade, and prevention of generation | occurrence | production of unusual noise.
However, since the elastic power of the edge layer is less than 40%, the edge portion is slightly plastically deformed by sliding with the contacted member, and the toner and nip at the nip between the edge portion and the contacted member The amount of toner external additive slipping increased. As the toner and the toner external additive slip through the edge portion, the blade edge is worn and the cleaning function in a low temperature environment is deteriorated.

(Comparative Examples 9 and 10)
In the cleaning blades of Comparative Examples 9 and 10, the elastic power of the backup layer is less than 70%. When the elastic power of the backup layer is less than 70%, the backup layer is plastically deformed by the bending stress of the blade. In the two-layer blade described in this embodiment, the backup layer is thicker than the edge layer, and the deformation of the entire blade is dominated by the deformation of the backup layer. This causes the entire blade to sag and causes a cleaning failure due to a decrease in linear pressure.

From the result of the verification experiment shown in Table 1, the elastic power of the edge layer is preferably 40% or more.
By setting the elastic power of the edge layer to 40% or more, it is possible to suppress the cleaning failure caused by the plastic deformation of the edge portion. When the elastic power of the edge layer is less than 40%, as described in Comparative Examples 7 and 8, the edge part is slightly plastically deformed by sliding with the contacted member, and the edge part is in contact with the edge part. The amount of toner and toner external additives slipping through the nip with the member increases. When the toner and the toner external additive slip through the edge portion, the edge portion is worn and the cleaning function in a low temperature environment is deteriorated.

  If the elastic power of the edge layer is 90% or more, the hardness value tends to decrease generally as the elastic power value increases, so that the hardness of the edge layer decreases and the edge portion is formed on the photoconductor. There is a possibility that wear of the edge portion due to the pull-in occurs. Therefore, it is desirable that the elastic power of the edge layer is less than 90%.

Further, the elastic power of the backup layer is preferably 70% or more.
By setting the elastic power of the backup layer to 70% or more, it is possible to suppress the settling of the cleaning blade due to plastic deformation of the backup layer.
If the elastic power of the backup layer is less than 70%, the backup layer is plastically deformed, so that the entire cleaning blade is damaged, and a cleaning failure occurs due to a decrease in linear pressure.
Moreover, although there is no upper limit in the preferable range of the elastic power of the backup layer in the present embodiment, the elastic power of general urethane rubber is generally less than 95%.

[Verification experiment 2]
Next, Martens hardness was measured about the cleaning blades of Examples 1 to 14 and Comparative Examples 1 to 8 of the verification experiment 1, and the presence or absence of filming was evaluated.

[Martens hardness]
The Martens hardness is calculated simultaneously with calculating the elastic power. As with the calculation of the elastic power, the Martens hardness is pushed for 10 seconds with a force of 1.0 [mN] from the edge ridge line portion with a force of 1.0 [mN], held for 5 seconds, and measured for 10 seconds. To do.

As shown in FIG. 4, in the cleaning blade 5 having a two-layer structure, when the thickness of the edge layer 6 is very small compared to the thickness of the backup layer 7, the Martens hardness of the edge layer 6 from the blade facing surface 62 side. This measurement value may be affected by the Martens hardness of the backup layer 7.
For example, when the Martens hardness of the edge layer 6 is affected by the Martens hardness of the backup layer 7 when the Martens hardness of the edge layer 6 is higher than the Martens hardness of the backup layer 7 in the measurement of the Martens hardness of the edge layer 6. However, it will be measured lower than the result of measuring the Martens hardness with the single material used for the edge layer 6.

As a result of the applicant's earnest research, even if the thickness of the edge layer 6 is very thin compared to the thickness of the backup layer 7 by measuring the Martens hardness of the edge layer 6 using the following method. It was found that the Martens hardness of the edge layer 6 can be accurately measured.
First, the Martens hardness of the edge layer 6 measured from the blade facing surface 62 side of the cleaning blade 5 is A, the Martens hardness of the edge layer measured from the blade tip surface 63 side of the cleaning blade 5 is B, and the blade tip surface of the cleaning blade 5 The Martens hardness of the backup layer measured from the 63 side is C. Then, the difference between A and C and the difference between B and C are calculated, respectively, and set as the Martens hardness of the edge layer 6 having the larger absolute value of the difference value. That is, when the absolute value of the difference between B and C is larger than the difference between A and C, the value of A is set. When the absolute value of the difference between A and C is larger than the difference between B and C, B is set. Is the Martens hardness of the edge layer 6.
In this verification experiment, the Martens hardness values selected using this method are shown in Table 2.

[Evaluation item]
(Existence of filming)
10,000 images were output continuously in an environment of 54 ° C. at 32 ° C. As an output image, a full-color image was output on A4 recording paper so as to maximize the toner input to the photoconductor, and the presence or absence of filming was evaluated in two stages according to the following criteria.
○: Filming is not visually observed on the output image, and no abnormal image is observed.
X: Filming is visually observed on the output image, resulting in an abnormal image.

Table 2 shows the results of the verification experiments of the examples and comparative examples in this verification experiment.

Example 1
In the cleaning blade of Example 1, the Martens hardness of the edge layer is 1.1 [N / mm ² ], the Martens hardness of the backup layer is 0.8 [N / mm ² ], and the Martens hardness of the edge layer is 1. 0 [N / mm ² ] or more.
In the cleaning blade of Example 1, the Martens hardness of the edge layer is set to 1.0 [N / mm ² ] or more, so that the filming of the toner external additive adhering to the surface of the image carrier can be suppressed. It was. The details are as follows.

FIG. 11 is an explanatory view of the wear of the edge portion 261 of the conventional cleaning blade 105.
As shown in FIG. 11A, when the edge portion 261 of the cleaning blade 105 comes into contact with the surface of the contacted member 110 whose surface moves in the direction of the arrow in the drawing, the Martens hardness of the edge portion 261 is 1.0 [ If it is less than N / mm ² ], the following problems occur.
If the Martens hardness of the edge portion 261 is less than 1.0 [N / mm ² ], the deformation of the edge portion 261 that occurs when a load is applied becomes large, and the cleaning blade 105 is brought into contact with the contacted member 110. In this case, the contact area and the nip width between the contacted member 110 and the edge portion 261 increase.

  Further, since the edge portion 261 is soft, as shown in FIG. 11B, the amount of the edge portion 261 that is pulled in with respect to the surface movement direction of the contacted member 110 increases, and the edge portion 261 is greatly deformed. . When the nip width between the contacted member 110 and the edge portion 261 is large and the deformation of the edge portion 261 is large, the contact pressure of the edge portion 261 is dispersed, and the adhered matter on the surface of the contacted member 110 is scraped off. I can't. Further, if the edge portion 261 is largely deformed, a load is applied to the edge, which causes wear and chipping as shown in FIG.

In the cleaning blade of Example 1, the Martens hardness of the edge layer was set to 1.0 [N / mm ² ] or more. Thereby, the deformation of the edge portion that occurs when a load is applied to the edge portion is reduced, and the contact area and the nip width of the tip ridge line portion when the cleaning blade is brought into contact with the contacted member are reduced. In addition, since the edge portion is hard, the amount of the edge portion that is pulled in with respect to the rotation direction of the photoconductor, which is a member to be abutted, is reduced, so that the blade edge portion is not easily deformed. Thus, when the nip width is small and the edge deformation is small, the contact state of the edge portion with respect to the contacted member is stabilized, and the fixed matter on the contacted member can be scraped off. Furthermore, since the deformation of the edge portion is small, the load generated at the edge portion is reduced, and wear and chipping at the tip ridge line portion of the cleaning blade can be suppressed.

When the Martens hardness of the edge layer is 10 [N / mm ² ] or more, the following problems occur.
Urethane rubber used as a material for the cleaning blade generally tends to have a lower elastic power as the hardness increases. Therefore, increasing the hardness of the cleaning blade decreases the elastic power. In the cleaning blade having a reduced elastic power, the edge portion of the cleaning blade is plastically deformed by sliding with the contacted member, and the edge portion is worn. Therefore, the Martens hardness of the edge layer is preferably less than 10 [N / mm ² ].

In the cleaning blade of Example 1, the Martens hardness of the edge layer is higher than that of the backup layer.
Urethane rubber material, which is widely used as a material for cleaning blades, reduces the rubber properties when the hardness of the urethane rubber material is increased to improve the removal ability to scrape off the deposits on the contacted member. The followability to the unevenness of the surface of the member is reduced. If the tracking low is lowered, the cleaning function is lowered due to an increase in the amount of toner passing through.
As in Example 1, the edge layer and the backup layer can be functionally separated by increasing the Martens hardness of the edge layer as compared with the Martens hardness of the backup layer. That is, even when the hardness of the edge layer is high enough to maintain the removal ability of the surface of the contacted member, the backed-up layer has a low hardness that can maintain rubber properties, so that the contacted member The followability of the entire blade with respect to the surface shape can be maintained.

(Examples 2 to 14)
In the cleaning blades of Examples 2 to 14, as in Example 1, the Martens hardness of the edge layer is 1.0 [N / mm ² ] or more, so that the toner external additive adheres to the surface of the image carrier. Filming could be suppressed.
In addition, since the Martens hardness of the edge layer is higher than the Martens hardness of the backup layer, even if the hardness of the edge layer is high enough to keep the removal ability of the surface of the contacted member high, The followability of the entire blade with respect to the surface shape of the contact member could be maintained.
The reason why such an evaluation is obtained is the same as that in the first embodiment, and thus the description thereof is omitted.

(Comparative Example 1)
The cleaning blade of Comparative Example 1 is a cleaning blade having a single layer structure, and the Martens hardness of the edge portion is 1.0 [N / mm ² ] or less.
Since the Martens hardness of the edge portion is 1.0 [N / mm ² ] or less, the nip width between the contacted member and the edge portion is increased, the contact pressure of the edge portion 261 is dispersed, and the contacted member The sticking matter on the surface of the film could not be scraped off. In addition, since the edge portion was greatly deformed, a load was applied to the edge portion, and the edge portion was worn or chipped. Filming occurred due to the dispersion of the contact pressure of the edge portion and the wear and chipping of the edge portion.

(Comparative Example 2)
The cleaning blade of Comparative Example 2 is a single layer structure cleaning blade. Further, the Martens hardness of the edge portion is 6.0 [N / mm ² ].
Urethane rubber used as a material for the cleaning blade generally tends to have a lower elastic power as the hardness increases. Therefore, when the hardness of the cleaning blade is increased in order to improve the filming resistance, the elastic power decreases.
Since the cleaning blade of Comparative Example 2 is a single-layered cleaning blade and uses a material with high hardness and low elastic work rate, the deformation that occurs when force is applied to the blade is the ratio of plastic deformation to elastic deformation. Become more. As a result, settling on the cleaning blade occurred.

(Comparative Examples 3-5)
The cleaning blades of Comparative Examples 3 to 5 are cleaning blades having a two-layer structure of an edge layer and a backup layer. Moreover, unlike Examples 1-14, the Martens hardness of an edge layer is 1.0 [N / mm < ² >] or less.
Since the Martens hardness of the edge portion is 1.0 [N / mm ² ] or less, the nip width between the photosensitive member and the edge portion increases, the contact pressure of the edge portion 261 is dispersed, and the surface of the contacted member The sticking material above could not be scraped off. Further, since the edge portion is greatly deformed, a load is applied to the edge portion, and the edge portion is worn or chipped. Filming occurred due to the dispersion of the contact pressure of the edge portion and the wear and chipping of the edge portion.

(Comparative Example 6)
The cleaning blade of Comparative Example 6 is a cleaning blade having a two-layer structure of an edge layer and a backup layer. Moreover, unlike Examples 1-14, the Martens hardness of a backup layer is high compared with the Martens hardness of an edge layer.
In the cleaning blade of Comparative Example 6, since the Martens hardness of the edge layer was 1.0 [N / mm ² ] or more, the occurrence of filming could be suppressed. However, since the Martens hardness of the backup layer is higher than the Martens hardness of the edge layer, the rubber property of the entire cleaning blade is deteriorated. When the rubber property of the entire cleaning blade is lowered, the followability to the irregularities on the surface of the photoreceptor is lowered, so that the cleaning function is lowered due to an increase in the amount of toner slipping, resulting in poor cleaning.

(Comparative Examples 7 and 8)
In the cleaning blades of Comparative Examples 7 and 8, the Martens hardness of the edge layer is 1.0 [N / mm ² ] or more. Further, similarly to Examples 1 to 14, the Martens hardness of the edge layer is higher than the Martens hardness of the backup layer.
Since the Martens hardness of the edge layer was 1.0 [N / mm ² ] or more, filming did not occur.

(Comparative Examples 9 and 10)
In the cleaning blades of Comparative Examples 9 and 10, the edge layer has a Martens hardness of 1.0 [N / mm ² ] or more. Further, similarly to Examples 1 to 14, the Martens hardness of the edge layer is higher than the Martens hardness of the backup layer. For this reason, filming did not occur.
Further, in the cleaning blades of Comparative Examples 9 and 10, since the elastic power of the backup layer was less than 70%, cleaning failure occurred due to the settling of the blade.

Next, an embodiment of an electrophotographic printer (hereinafter simply referred to as a printer) will be described as an image forming apparatus in which the blade member of the present invention is applied to a cleaning device. First, a basic configuration of the printer according to the present embodiment will be described.
FIG. 5 is a schematic configuration diagram of the printer 100 according to the present embodiment.
The printer 100 forms a full-color image, and generally includes an image forming unit 120, an intermediate transfer device 160, and a paper feeding unit 130. In the following description, the subscripts Y, C, M, and Bk indicate members for yellow, cyan, magenta, and black, respectively.

  The image forming unit 120 includes a process cartridge 121Y for yellow toner, a process cartridge 121C for cyan toner, a process cartridge 121M for magenta toner, and a process cartridge 121Bk for black toner. These process cartridges 121 (Y, C, M, Bk) are arranged in a line in a substantially horizontal direction. The process cartridge 121 (Y, C, M, Bk) is detachably attached to the printer 100 as a unit.

  The intermediate transfer device 160 includes an endless intermediate transfer belt 162 that is stretched around a plurality of support rollers, a primary transfer roller 161 (Y, C, M, Bk), and a secondary transfer roller 165. The intermediate transfer belt 162 is provided on each process cartridge 121 (Y, C, M, Bk) above each process cartridge 121 (Y, C, Drum-like photoreceptor 10 (Y, C) as a latent image carrier that moves on the surface. , M, Bk) along the surface movement direction. The intermediate transfer belt 162 moves on the surface in synchronization with the surface movement of the photoreceptor 10 (Y, C, M, Bk). Each primary transfer roller 161 (Y, C, M, Bk) is disposed along the inner peripheral surface of the intermediate transfer belt 162, and intermediate transfer is performed by these primary transfer rollers 161 (Y, C, M, Bk). The surface of the belt 162 is in weak pressure contact with the surface of each photoconductor 10 (Y, C, M, Bk).

  The configuration and operation of forming a toner image on each photoconductor 10 (Y, C, M, Bk) and transferring the toner image to the intermediate transfer belt 162 are the same as each process cartridge 121 (Y, C, M, Bk). Is substantially the same. However, the primary transfer roller 161 (Y, C, M) corresponding to the three process cartridges 121 (Y, C, M) for color is provided with a swing mechanism (not shown) that swings them up and down. . The swing mechanism operates so that the intermediate transfer belt 162 does not contact the photoconductor 10 (Y, C, M) when a color image is not formed. In order to remove deposits on the intermediate transfer belt 162 such as residual toner after the secondary transfer on the downstream side of the secondary transfer roller 165 of the intermediate transfer belt 162 in the surface moving direction and on the upstream side of the process cartridge 121Y. The intermediate transfer belt cleaning device 167 is provided.

  Above the intermediate transfer device 160, toner cartridges 159 (Y, C, M, Bk) corresponding to the process cartridges 121 (Y, C, M, Bk) are arranged in a substantially horizontal direction. Further, below the process cartridge 121 (Y, C, M, Bk), an electrostatic latent image is formed by irradiating the surface of the charged photoconductor 10 (Y, C, M, Bk) with laser light. An exposure device 140 is arranged.

The paper feeding unit 130 is disposed below the exposure device 140. The paper supply unit 130 is provided with a paper supply cassette 131 and a paper supply roller 132 for storing transfer paper as a recording medium. The transfer paper is fed at a predetermined timing toward the secondary transfer nip portion between the intermediate transfer belt 162 and the secondary transfer roller 165 via the registration roller pair 133.
A fixing device 30 is disposed on the downstream side of the secondary transfer nip portion in the transfer paper conveyance direction. The discharge roller and the discharged transfer paper are accommodated on the downstream side of the fixing device 30 in the transfer paper conveyance direction. A paper discharge storage unit 135 is disposed.

FIG. 6 is a schematic configuration diagram of an example of the process cartridge 121 provided in the printer 100.
Here, since the configuration of each process cartridge 121 (Y, C, M, Bk) is almost the same, the subscripts Y, C, M, Bk for color coding are omitted in the following description, and the process cartridge 121 The configuration and operation will be described.
The process cartridge 121 includes a drum-shaped photoconductor 10, a cleaning device 1 disposed around the photoconductor 10, a charging unit 40, and a developing unit 50.
The cleaning device 1 includes a leading edge ridge line (edge) that is an edge ridge line extending in a direction perpendicular to the rotation direction of the photoconductor in the cleaning blade 5 that is a strip-shaped elastic blade elongated in the rotation axis direction of the photoconductor 10. Part) 61 is pressed against the surface of the photoreceptor 10. Thereby, unnecessary deposits such as transfer residual toner on the surface of the photoconductor 10 are separated and removed. The removed deposits such as toner are discharged out of the cleaning device 1 by the discharge screw 43.

The charging unit 40 is mainly composed of a charging roller 41 facing the photoconductor 10 and a charging roller cleaner 42 that rotates in contact with the charging roller 41.
The developing unit (developing device) 50 supplies toner to the surface of the photoreceptor 10 to make the electrostatic latent image visible, and a developer carrying member that carries the developer (carrier, toner) on the surface. The developing roller 51 is provided. The developing unit 50 includes the developing roller 51, an agitating screw 52 that conveys the developer accommodated in the developer accommodating unit while agitating, and a supply screw 53 that conveys the agitated developer while supplying the developer to the developing roller 51. And is mainly composed of.

  The four process cartridges 121 having the above-described configuration can be detached and replaced independently by a service person or a user. Further, with respect to the process cartridge 121 removed from the printer 100, the photoconductor 10, the charging unit 40, the developing unit 50, and the cleaning device 1 are each configured to be replaceable with a new device. The process cartridge 121 may include a waste toner tank that collects the transfer residual toner collected by the cleaning device 1. In this case, if the configuration is such that the waste toner tank can be detached and replaced independently in the process cartridge 121, the convenience is improved.

Next, the operation of the printer 100 will be described.
The printer 100 receives a print command from an external device such as an operation panel (not shown) or a personal computer. First, the photoconductor 10 is rotated in the moving direction (rotation direction) A indicated by the arrow in FIG. 6, and the surface of the photoconductor 10 is uniformly charged to a predetermined polarity by the charging roller 41 of the charging unit 40. The exposure device 140 irradiates, for example, laser beam light, which is light-modulated in accordance with the input color image data, on the surface of each photoconductor 10 with respect to the surface of each photoconductor 10. The electrostatic latent image is formed. Each electrostatic latent image is supplied with a developer of each color from the developing roller 51 of the developing unit 50 of each color, and the electrostatic latent image of each color is developed with the developer of each color to form a toner image corresponding to each color. To visualize it.

  Next, a primary transfer electric field is formed between the photoreceptor 10 and the primary transfer roller 161 with the intermediate transfer belt 162 interposed therebetween by applying a transfer voltage having a polarity opposite to that of the toner image to the primary transfer roller 161. At the same time, a primary transfer nip is formed by weakly pressing the intermediate transfer belt 162 with the primary transfer roller 161. By these actions, the toner image on each photoconductor 10 is efficiently primary-transferred onto the intermediate transfer belt 162. On the intermediate transfer belt 162, the toner images of the respective colors formed on the respective photoconductors 10 are transferred so as to overlap each other, thereby forming a laminated toner image.

  For the laminated toner image primarily transferred onto the intermediate transfer belt 162, the transfer paper stored in the paper feed cassette 131 is fed at a predetermined timing via the paper feed roller 132, the registration roller pair 133, and the like. The Then, by applying a transfer voltage having a polarity opposite to that of the toner image to the secondary transfer roller 165, a secondary transfer electric field is formed between the intermediate transfer belt 162 and the secondary transfer roller 165 with the transfer paper interposed therebetween. The laminated toner image is transferred onto the paper. The transfer paper onto which the laminated toner image has been transferred is sent to the fixing device 30 and fixed by heat and pressure. The transfer paper on which the toner image is fixed is discharged and placed in the paper discharge storage unit 135 by the paper discharge roller. On the other hand, the transfer residual toner remaining on each photoconductor 10 after the primary transfer is scraped and removed by the cleaning blade 5 of each cleaning device 1.

Note that as the charging unit, a contact charging roller that applies an alternating voltage to a direct current voltage on the image carrier may be used. As a result, the charging current is large and the charging potential on the surface of the image carrier is stabilized, so that high image quality and long life can be achieved.
In addition, when an AC voltage is applied to the charging member, the vibration of the cleaning blade edge becomes noticeable due to the vibration of the image carrier, causing abnormal noise due to vibration, blade wear or chipping, and abnormal photoconductor wear. Become. In this embodiment, since the cleaning blade having a laminated structure in which the elastic power of the edge layer is lower than the elastic power of the backup layer is used, generation of abnormal noise due to vibration generated by applying an AC voltage to the charging member, Blade wear and chipping and abnormal wear of the photoreceptor can be suppressed.

Next, another process cartridge to which the cleaning blade of this embodiment can be applied will be described.
FIG. 7 is a schematic configuration diagram illustrating another example of a process cartridge provided in the printer of the present embodiment.
The process cartridge 122 has a configuration in which a protective agent application device 70 for applying a protective agent, which is a lubricant, is provided on the surface of the photoreceptor 10. In the process cartridge 122, a roller member that charges the photoreceptor 10 in contact with or without contact with the photoreceptor 10 is used as the charging roller 41, and an AC voltage is applied to the charging roller 41. The protective agent coating device 70 is provided on the downstream side of the cleaning device 1 in the moving direction A of the photoconductor 10. Thereby, the protective agent can be stably applied to the photoreceptor 10.

  In the protective agent coating device 70, a rod-shaped solid protective agent 72 is held by a holding cylinder 71 and is urged toward the photosensitive member 10 by a compression spring 73 in the holding cylinder 71. A rotating urethane foam roller 77 is disposed between the solid protective agent 72 and the photoconductor 10, and the solid protective agent 72 is scraped off and applied to the surface of the photoconductor 10 by the rotation of the urethane foam roller 77. ing. Further, an application blade 75 made of polyurethane or the like is disposed on the downstream side of the urethane foam roller 77, so that the protective agent applied to the surface of the photoreceptor 10 can be thinned.

  The foamed urethane roller 77 is rotationally driven in the direction opposite to the moving direction A of the photosensitive member 10, and the rotational protective drive applies the protective agent of the solid protective agent 72 to the surface of the photosensitive member 10. Further, the coating blade 75 is in contact with the photoconductor 10 from the trailing direction, so that the protective agent can be thinned with good coating efficiency without scraping off the protective agent from the photoconductor 10.

  The protective agent contains a fatty acid metal salt and an inorganic lubricant. In such a protective agent, since the fatty acid metal salt is destroyed by the charging current, the surface of the photoreceptor 10 is prevented from being destroyed. At the same time, since the lubricating action of the protective agent is maintained in a better state than when only the fatty acid metal salt is used due to the inorganic lubricant that is not destroyed by the charging current, the cleaning of the photoconductor 10 can be maintained better. It becomes possible.

  Examples of fatty acid metal salts include barium stearate, lead stearate, iron stearate, nickel stearate, cobalt stearate, copper stearate, strontium stearate, calcium stearate, cadmium stearate, magnesium stearate, zinc stearate, olein Zinc acid, Magnesium oleate, Iron oleate, Cobalt oleate, Copper oleate, Lead oleate, Manganese oleate, Zinc palmitate, Cobalt palmitate, Lead palmitate, Magnesium palmitate, Aluminum palmitate, Calcium palmitate , Lead caprylate, lead caprate, zinc linolenate, cobalt linolenate, calcium linolenate, zinc ricinoleate, cadmium ricinoleate and mixtures thereof, The present invention is not limited in Les. Moreover, you may mix and use these. In this case, zinc stearate is most preferably used because it is particularly excellent in film formability on the photoreceptor 10.

  Inorganic lubricants are inorganic compounds that cleave and lubricate themselves or cause internal slip. Specific examples include talc, mica, boron nitride, molybdenum disulfide, tungsten disulfide, kaolin, smectite, hydrotalcite compound, calcium fluoride, graphite, plate-like alumina, sericite, and synthetic mica. However, it is not limited to this. In this case, boron nitride is most preferably used because the hexagonal mesh planes in which atoms are tightly combined overlap with each other at a wide interval and only the van der Waals force acting between layers is weak, so that it is easily cleaved and lubricated. These inorganic lubricants may be surface-treated as necessary for the purpose of imparting hydrophobicity.

[Verification Experiment 3]
Next, a description will be given based on a third verification experiment (hereinafter referred to as verification experiment 3).
For the cleaning blade in which the edge layer 6 of the cleaning blade 5 having a two-layer structure shown in FIG. 1 has an elastic power of less than 40%, the elastic power of the edge layer and the backup layer are changed to lubricate the photoreceptor. The cleaning functionality in a low temperature environment was evaluated in each of the case where the material was applied and the case where the lubricant was not applied.

(Presence or absence of poor cleaning in low temperature and low humidity environment)
Using a Ricoh MPC3503 machine as an experimental machine, in the process cartridge configured as shown in FIG. 7, the cleaning blades were changed to the cleaning blades having the conditions of Examples 15 to 18 and Comparative Examples 11 to 14 in Table 3, respectively. The measurement was performed when the lubricant was applied to the body and when the lubricant was not applied.
The test machine was allowed to stand for 24 hours in a low-temperature and low-humidity environment (10 ° C. and 15%) where cleaning failure tends to occur, and 8000 images were continuously output in an environment of 10 ° C. and 15%. The output image was a solid image on A4 recording paper so as to maximize toner input to the photoreceptor. Then, it was visually observed whether or not a cleaning failure was apparent on the paper, and evaluated as follows.
○: Good cleaning property. After passing 8,000 sheets, there is no problem in actual use because no cleaning defect appears on the paper.
X: Cleaning failure occurred. After passing 8,000 sheets, the cleaning defect is alive on the paper, and there is a problem as an abnormal image in actual use.

Table 3 shows the results of the verification experiments of the examples and comparative examples in this verification experiment.

(Example 15)
As the cleaning blade of Example 15, a cleaning blade having a two-layer structure of an edge layer and a backup layer was used. In this cleaning blade, the elastic power of the backup layer is higher than that of the edge layer, and the elastic power of the edge layer is less than 40% and 30% or more.
When the elastic power of the edge layer is less than 40%, the edge portion of the cleaning blade is plastically deformed by sliding with the photoreceptor. Due to this plastic deformation, the toner slip-through amount increases, and the increase in the toner slip-through amount wears the edge of the cleaning blade, resulting in poor cleaning.
In the cleaning blade of Example 1, the friction between the cleaning blade and the photoconductor is reduced by applying a lubricant to the surface of the photoconductor. By reducing this friction, the load applied to the edge portion of the cleaning blade is reduced, and wear of the edge portion of the cleaning blade is suppressed. Therefore, it was possible to suppress poor cleaning in a low temperature environment.

(Examples 16 to 18)
As the cleaning blades of Examples 16 to 18, cleaning blades in which the elastic power of the edge layer and the elastic power of the backup layer were changed to the values shown in Table 3 from the configuration of Example 1 were used. As in Example 1, the elastic power of the edge layer is 40%, less than 30%, and the lubricant function is applied to the surface of the photoconductor to suppress the deterioration of the cleaning function. The reason why such an evaluation is obtained is the same as that in the first embodiment, and thus the description thereof is omitted.

(Comparative Example 11)
The cleaning blade of Comparative Example 11 has the same configuration as the cleaning blade of Example 1 in the relationship between the elastic power of the backup layer and the elastic power of the edge layer, but the lubricant is not applied to the photoconductor. . Since the elastic power of the edge layer is less than 40% and no lubricant is applied to the photoconductor, the friction between the photoconductor and the cleaning blade increases, and the edge portion of the cleaning blade is caused by sliding with the photoconductor. Is plastically deformed. Due to this plastic deformation, the amount of toner slip increases, and the edge portion of the cleaning blade wears due to the increase of the toner slip amount. This caused a cleaning failure due to blade edge wear in a low temperature environment.

(Comparative Examples 12-13)
Similar to Comparative Example 11, the elastic power of the edge layer is less than 40%, and no lubricant is applied to the photoreceptor. For this reason, the cleaning defect resulting from abrasion of a blade edge occurred. The reason why such an evaluation is obtained is the same as that of Comparative Example 11, and thus the description thereof is omitted.

From the result of the verification experiment shown in Table 3, it is preferable that a lubricant is applied to the photosensitive member which is a contact member with which the cleaning blade contacts. By applying a lubricant to the photoconductor, the friction between the blade and the photoconductor can be reduced. By reducing this friction, the load on the edge of the cleaning blade is reduced, and the edge of the cleaning blade is reduced. Wear is suppressed. Accordingly, it is possible to suppress a cleaning failure in a low temperature environment.
Further, when a lubricant is applied to the photoreceptor, the elastic power of the edge layer of the cleaning blade is preferably 30% or more. Thereby, even when the elastic power of the edge layer of the cleaning blade is less than 40%, it is possible to suppress the deterioration of the cleaning function due to the plastic deformation of the edge portion of the cleaning blade.
In this verification experiment, a urethane rubber material having an elastic work rate of 30% or more was used in order to maintain the rubber property of the material. If the elastic power of the edge layer is less than 30%, the rubber property of the material cannot be maintained.

Next, still another process cartridge to which the cleaning blade of this embodiment can be applied will be described.
FIG. 8 is a schematic configuration diagram showing still another example of a process cartridge provided in the printer of this embodiment.
The process cartridge 123 employs a spring pressurization system using a pressurization mechanism 80 using a spring 81 as a cleaning blade pressurization system that pressurizes and contacts the cleaning blade against the surface of the photoreceptor. This spring pressure method is a constant contact pressure method in which the contact pressure of the cleaning blade with respect to the photoconductor becomes a constant value over time.
The pressing mechanism 80 of the cleaning blade 5 presses the edge portion 61 of the cleaning blade 5 against the photosensitive member 10 by the tension of the spring 81 with the rotation support portion 82 provided on the support member 3 of the cleaning blade 5 as a fulcrum. It is carried out. In this embodiment, the applied pressure of the cleaning blade edge portion 61 is 20.0 [g / cm].

  In the process cartridge 123, a roller member that contacts the photoreceptor 10 and charges the photoreceptor 10 is used as the charging roller 41, and an alternating voltage is applied to the charging roller 41. An AC voltage is applied to the charging roller 41, and the surface of the photoconductor is uniformly charged by rotating while contacting the photoconductor.

[Verification experiment 4]
Next, a description will be given based on a fourth verification experiment (hereinafter referred to as verification experiment 4).
In the cleaning blade 5 having a two-layer structure as shown in FIG. 1, the cleaning blade pressurization method and the elastic power of the edge layer and the backup layer are changed for the cleaning blade whose backup layer 7 has an elastic power of less than 70%. The effect of cleaning blades on the cleaning performance was evaluated.

(Cleaning blade pressurization method)
In the process cartridge having the configuration shown in FIG. 8, the measurement was performed by changing the cleaning blade pressurization method to the constant contact pressure method or the constant biting amount method. In the constant contact pressure method, the contact pressure of the cleaning blade with respect to the photoconductor is pressurized so as to become a constant value over time by the spring pressurization by the spring 81. In the constant biting amount method, the biting amount of the cleaning blade edge portion with respect to the photosensitive member of the supporting member 3 of the cleaning blade 5 shown in FIG. 8 is a predetermined value (0.8 [mm] to 1.1 [mm]). Is fixed so that the amount of biting of the edge portion of the cleaning blade with respect to the photosensitive member becomes constant.

(Blade Hetari)
Using a Ricoh MPC3503 machine as an experimental machine, in the process cartridge having the configuration shown in FIG. 8, the cleaning blade was changed to blade members having the conditions of Examples 19 to 22 and Comparative Examples 15 to 16 in Table 1, and measurement was performed. went.
Using the experimental device, the cleaning blade is left in contact with the image carrier for 7 days (168 hours) in a normal room environment (23 ° C. and 50%), before and after contact. The blade edge contact pressure is measured. A change in contact pressure over time, which is caused by bringing the cleaning blade into contact with the image carrier and holding the blade in a state where pressure is applied thereto, is compared. The contact pressure when contacting the image carrier is 20 [g / cm].
The influence on the cleaning property due to the settling was performed under a high charging current condition in which cleaning failure is likely to occur, and was evaluated as follows.
◯: Less than 4.0 [g / cm] (20% of the set linear pressure) linear pressure drop. No effect on cleaning performance.
X: The amount of linear pressure reduction is 4.0 [g / cm] (20% of the set linear pressure) or more. There is an effect on cleaning performance.

Table 4 shows the results of the verification experiments of the examples and comparative examples in this verification experiment.

(Example 19)
As the cleaning blade of Example 19, a cleaning blade having a two-layer structure of an edge layer and a backup layer was used. In this cleaning blade, the elastic power of the backup layer is larger than the elastic power of the edge layer, and the elastic power of the backup layer is 50% or more and less than 70%.
As the elastic power of the backup layer is lower, the cleaning blade is more likely to be plastically deformed due to the bending stress applied to the cleaning blade, and the cleaning blade is likely to be set. When the constant amount of biting is used as the cleaning blade pressurizing method, the amount of biting does not change even when settling occurs in the blade. Therefore, when the settling occurs in the cleaning blade, the linear pressure decreases and defective cleaning occurs.

  On the other hand, the cleaning blade of Example 19 employs a constant contact pressure method by the pressurizing mechanism 80 shown in FIG. In the constant contact pressure method, the contact pressure becomes a constant value over time, so that even if the cleaning blade is set, the linear pressure does not decrease. Accordingly, it is difficult for the cleaning function to decrease due to the decrease in linear pressure. The amount of decrease in linear pressure in Example 1 was 0.4 [g / cm], and no significant decrease in linear pressure occurred, so there was no effect on cleaning properties.

(Examples 20 to 22)
The cleaning blades of Examples 20 to 22 have the same configuration as that of Example 1 except that the elastic power of the edge layer and the elastic power of the backup layer are changed to the values shown in Table 4 from the configuration of Example 1. It was.
The amount of decrease in linear pressure over time is 0.4 to 0.6 [g / cm], and no significant decrease in linear pressure has occurred. For this reason, there is no influence on the cleaning property. The reason why such an evaluation is obtained is the same as that in the first embodiment, and thus the description thereof is omitted.

(Comparative Example 15)
In the cleaning blade of Comparative Example 15, the relationship between the elastic power of the backup layer and the elastic power of the edge layer is the same as that of the cleaning blade of Example 19, and the elastic power of the backup layer is 50% or more and 70%. Is less than. However, unlike the cleaning blade of the first embodiment, the cleaning blade pressurization method is a constant biting amount method.
The lower the elastic power of the backup layer is, the more the blade is plastically deformed by the bending stress applied to the cleaning blade, thereby causing the cleaning blade to stick. With the constant biting amount method, the linear pressure drops due to the settling of the cleaning blade over time, resulting in poor cleaning.
As a result of measuring the change in linear pressure after leaving the cleaning blade of Comparative Example 1 in contact with the image carrier for 168 hours, the linear pressure decrease amount was 4.1 [g / cm]. This is a value larger than the linear pressure reduction amount 4.0 [g / cm] (20% of the set linear pressure) at which the cleaning failure occurs due to the linear pressure drop in the MPC3503 machine. Occurred.

(Comparative Example 16)
In the cleaning blade of Comparative Example 16, the elastic power of the backup layer is 50% or more and less than 70% as in Comparative Example 1. However, in the cleaning blade of Comparative Example 2, since the cleaning blade pressurization method is a constant encroachment amount method, the linear pressure decreased with time, and cleaning failure occurred. The reason why such an evaluation is obtained is the same as that of the cleaning blade of Comparative Example 1, and thus the description thereof is omitted.

  From the results of the verification experiment shown in Table 4, it is preferable that the cleaning blade pressurization method adopts a constant contact pressure method. By setting the cleaning blade pressurization method to a constant contact pressure method, the contact pressure becomes a constant value over time, so that even if the cleaning blade is set, the linear pressure does not decrease. Accordingly, it is possible to make it difficult for the cleaning function to decrease due to the decrease in linear pressure.

  Further, when the cleaning blade pressurization method is a constant contact pressure method, the elastic power of the backup layer is preferably 50% or more. Thereby, even when the elastic power of the backup layer is less than 70%, a decrease in linear pressure over time can be suppressed.

Next, a photoconductor used as an image carrier in the image forming apparatus will be described.
FIG. 9 is an explanatory diagram of the layer structure of the photoconductor 10 that can be used in this embodiment. FIG. 9A shows an example of a cross section of the photoreceptor 10 in which a photosensitive layer 92 containing inorganic fine particles is laminated in the vicinity of the surface on a conductive support 91. FIG. 9B is an example showing a cross section of the photoreceptor 10 in which a photosensitive layer 92 and a surface layer 93 containing inorganic fine particles are sequentially laminated on a conductive support 91. In FIG. 9C, a photosensitive layer 92 in which a charge generation layer 921 and a charge transport layer 922 are sequentially laminated is disposed on a conductive support 91, and a surface layer 93 containing inorganic fine particles is further laminated on the photosensitive layer 92. 2 is an example showing a cross section of the photoconductor 10 provided. In FIG. 9D, an undercoat layer 94 is provided on a conductive support 91, a photosensitive layer 92 in which a charge generation layer 921 and a charge transport layer 922 are sequentially laminated is laminated on the undercoat layer 94, and further a photosensitive layer. 2 is an example showing a cross section of the photoconductor 10 provided by laminating a surface layer 93 containing inorganic fine particles on 92.

The photoreceptor 10 of this embodiment may have a structure in which at least a photosensitive layer 92 and a surface layer 93 are laminated on a conductive support 91, and other layers may be arbitrarily combined.
As shown in FIG. 9A, when the photosensitive layer 92 is the outermost layer, the photosensitive layer 92 contains inorganic fine particles. As shown in FIGS. 9C and 9D, when the photosensitive layer 92 has a structure in which a charge generation layer 921 and a charge transport layer 922 are sequentially stacked, the charge transport layer 922 becomes the outermost layer, and the charge transport layer 922 Inorganic fine particles are contained.

Inorganic fine particles include metal powders such as copper, tin, aluminum, indium, silicon oxide, silica, tin oxide, zinc oxide, titanium oxide, indium oxide, antimony oxide, bismuth oxide, tin oxide doped with antimony, tin Metal oxides such as indium oxide, and inorganic materials such as potassium titanate. In particular, metal oxides are good, and silicon oxide, aluminum oxide, titanium oxide and the like can be used effectively.
The average primary particle size of the inorganic fine particles is preferably 0.01 to 0.5 [μm] from the viewpoint of the light transmittance and wear resistance of the surface layer 93. When the average primary particle size of the inorganic fine particles is 0.01 [μm] or less, it causes a decrease in wear resistance, a decrease in dispersibility, and the like. There is a possibility that sedimentation of fine particles is promoted and toner filming may occur.

The higher the amount of inorganic fine particles added, the better the wear resistance and the better. However, when the amount is too high, the residual potential increases and the write light transmittance of the protective layer decreases, which may cause side effects. Therefore, it is generally 30% by weight or less, preferably 20% by weight or less, based on the total solid content. The lower limit is usually 3% by weight.
Further, these inorganic fine particles can be surface-treated with at least one kind of surface treatment agent, and it is preferable from the viewpoint of dispersibility of the inorganic fine particles.
A decrease in the dispersibility of inorganic fine particles not only increases the residual potential, but also decreases the transparency of the coating film, the occurrence of coating film defects, and a decrease in wear resistance. It can develop into a big problem to hinder.

Next, the photosensitive layer 92 will be described.
As shown in FIGS. 9B to 9D, the photoreceptor 10 has a surface layer 93 containing inorganic fine particles on the outermost surface of the photosensitive layer 92.
The surface layer 93 is composed of at least inorganic fine particles and a binder resin. The inorganic fine particles include copper, tin, aluminum, indium and other metal powders, silicon oxide, silica, tin oxide, zinc oxide, titanium oxide, indium oxide, antimony oxide, bismuth oxide, antimony-doped tin oxide and tin. Examples thereof include metal oxides such as doped indium oxide and inorganic materials such as potassium titanate. In particular, metal oxides are good, and silicon oxide, aluminum oxide, titanium oxide and the like can be used effectively.
The average primary particle size of the inorganic fine particles is preferably 0.01 to 0.5 [μm] from the viewpoint of the light transmittance and wear resistance of the surface layer 93.
When the average primary particle size of the inorganic fine particles is 0.01 [μm] or less, it causes a decrease in wear resistance, a decrease in dispersibility, and the like. There is a possibility that sedimentation of fine particles is promoted and toner filming may occur.

The higher the concentration of the inorganic fine particles in the surface layer 93, the higher the wear resistance and the better. However, if it is too high, the residual potential increases, the write light transmittance of the protective layer decreases, and side effects may occur. .
Therefore, it is approximately 50% by weight or less, preferably 30% by weight or less based on the total solid content. The lower limit is usually 5% by weight.
Further, these inorganic fine particles can be surface-treated with at least one kind of surface treatment agent, and it is preferable from the viewpoint of dispersibility of the inorganic fine particles.
A decrease in the dispersibility of inorganic fine particles not only increases the residual potential, but also decreases the transparency of the coating film, the occurrence of coating film defects, and a decrease in wear resistance. It can develop into a big problem to hinder.

As the surface treatment agent, a conventionally used surface treatment agent can be used, but a surface treatment agent capable of maintaining the insulating properties of the inorganic fine particles is preferable.
For example, titanate coupling agents, aluminum coupling agents, zircoaluminate coupling agents, higher fatty acids, etc., or mixed treatment of these with silane coupling agents, Al2O3, TiO2, ZrO2, silicone, aluminum stearate Or a mixture treatment thereof is more preferable from the viewpoint of dispersibility of inorganic fine particles and image blur.
The treatment with a silane coupling agent is strongly affected by image blur, but the effect may be suppressed by applying a mixture treatment of the above surface treatment agent and silane coupling agent. Depending on the average primary particle size of the inorganic fine particles used, 3-30 wt% is suitable, and 5-20 wt% is more preferred. If the surface treatment amount is less than this, the dispersion effect of the inorganic fine particles cannot be obtained, and if it is too much, the residual potential is significantly increased. These inorganic fine particle materials may be used alone or in combination of two or more. These inorganic fine particle materials can be dispersed by using an appropriate disperser. The average particle size of the inorganic fine particles in the dispersion is preferably 1 [μm] or less, and preferably 0.5 [μm] or less from the viewpoint of the transmittance of the surface layer 93.

As shown in FIGS. 9A to 9D, by containing inorganic fine particles on the surface of the photoconductor, it is possible to satisfactorily suppress an increase in frictional force due to the contact of the cleaning blade, and wear resistance of the surface of the photoconductor. Can be improved. In addition, by improving the wear resistance of the photoreceptor surface, it becomes possible to suppress the wear of the image carrier, particularly the uneven wear of the image carrier, and to improve the image quality, high stability, and durability of the electrophotographic system. It becomes possible.
Further, since the surface of the photoconductor contains inorganic fine particles, minute irregularities are generated on the surface of the photosensitive member, and the cleaning blade edge may vibrate due to the minute irregularities. Wear, chipping, or abnormal photoconductor wear may occur. In this embodiment, by using a cleaning blade having a laminated structure in which the elastic power of the edge layer is lower than the elastic power of the backup layer, abnormal noise due to vibration, blade wear and chipping, and abnormal photoconductor wear can be prevented. Can be deterred.

Next, a toner suitable for the image forming apparatus to which the present invention is applied will be described.
FIGS. 10A and 10B are explanatory diagrams of a method for measuring the circularity of the toner.
The toner used in the image forming apparatus to which the present invention is applied is a polymerized toner produced by suspension polymerization, emulsion polymerization, or dispersion polymerization, which is easy to increase the circularity and reduce the particle size in order to improve the image quality. It is preferable to use it. In particular, it is preferable to use a polymerized toner having a circularity of 0.97 or more and a volume average particle size of 5.5 [μm] or less. By using a material having an average circularity of 0.97 or more and a volume average particle size of 5.5 [μm], a higher resolution image can be formed.

  The “circularity” here is an average circularity measured by a flow type particle image analyzer FPIA-2000 (trade name, manufactured by Toa Medical Electronics Co., Ltd.). Specifically, a surfactant, preferably an alkylbenzene sulfonate, is added in an amount of 0.1 to 0.5 [ml] as a dispersant in 100 to 150 [ml] of water from which impure solids have been removed in advance. Further, about 0.1 to 0.5 [g] of a measurement sample (toner) is added. Thereafter, the suspension in which the toner is dispersed is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes so that the concentration of the dispersion becomes 3000 to 1 [10,000 / μl]. To measure the shape and distribution of the toner. Based on the measurement result, the outer peripheral length of the actual toner projection shape shown in FIG. 10A is C1, the projection area is S, and the outer circumference of the perfect circle shown in FIG. C2 / C1 was determined when the length was C2, and the average value was defined as the circularity.

The volume average particle diameter can be determined by a Coulter counter method. Specifically, the toner number distribution and volume distribution data measured by the Coulter Multisizer 2e type (manufactured by Coulter) are sent to a personal computer via an interface (manufactured by Nikkaki Co., Ltd.) for analysis.
More specifically, a 1% NaCl aqueous solution using first grade sodium chloride is prepared as an electrolytic solution. Then, 0.1 to 5 [ml] of a surfactant, preferably alkylbenzene sulfonate, is added as a dispersant to 100 to 150 [ml] of the electrolytic aqueous solution. Further, 2 to 20 [mg] of toner as a test sample is added thereto, and dispersion treatment is performed for about 1 to 3 [minutes] with an ultrasonic disperser. Then, 100 to 200 [ml] of the electrolytic aqueous solution is put into another beaker, and the solution after the dispersion treatment is added to the beaker so as to have a predetermined concentration, and the Coulter Multisizer 2e type is applied. The aperture is 100 [μm], and the particle size of 50,000 toner particles is measured.

  As a channel, it is less than 2.00-2.52 [micrometer]; 2.52-less than 3.17 [micrometer]; 3.17-less than 4.00 [micrometer]; 4.00-5.04 [micrometer] Less than 5.04 to 6.35 [μm]; 6.35 to less than 8.00 [μm]; 8.00 to less than 10.08 [μm]; 10.08 to less than 12.70 [μm]; 12.70 to less than 16.00 [μm]; 16.00 to less than 20.20 [μm]; 20.20 to less than 25.40 [μm]; 25.40 to less than 32.00 [μm]; Using 13 channels of 00 to less than 40.30 [μm], toner particles with a particle size of 2.00 [μm] or more and 32.0 [μm] or less are targeted.

  Then, the volume average particle diameter is calculated based on the relational expression “volume average particle diameter = ΣXfV / ΣfV”. However, “X” is the representative diameter in each channel, “V” is the equivalent volume in the representative diameter of each channel, and “f” is the number of particles in each channel.

What has been described above is merely an example, and the present invention has a specific effect for each of the following modes.
(Aspect A)
In a blade member such as the cleaning blade 5 in which the edge portion which is a tip ridge line portion such as the edge portion 61 of the elastic blade is brought into contact with the surface of the contacted member, the elastic blade includes the edge layer 6 having the edge portion and the like. It is a laminated structure having an edge layer and at least one layer such as a backup layer 7 on which the edge layer is laminated, and the elastic power of the layers other than the edge layer is larger than the elastic power of the edge layer. And big.

In this aspect, as described in the above embodiment, the amount of plastic deformation of the backup layer 7 that occurs when a bending or compression force is applied to the cleaning blade 5 is smaller than the amount of plastic deformation of the edge layer 6. And less. Thereby, even when the hardness of the edge layer 6 is increased, the settling of the entire cleaning blade 5 can be suppressed.
Further, when the photosensitive member 10 and the cleaning blade slide, a minute vibration is generated in the edge portion 61 of the cleaning blade. When this vibration and the natural frequency of the cleaning blade 5 coincide with each other, the edge layer 6 having the edge portion 61 is obtained. The vibration of is going to increase. At this time, the backup layer 7 having a higher elastic power than the elastic power of the edge layer 6 absorbs the vibration of the edge layer 6 and exhibits a vibration isolating function. Accordingly, it is possible to prevent the generation of abnormal noise due to minute vibration of the edge portion 61 due to sliding with the contacted member.

  Furthermore, by making the elastic power of the edge layer 6 lower than the elastic power of the backup layer 7, the backup layer 7 absorbs vibration due to the deformation of the edge layer 6, and the frequency and cleaning of the edge layer 6 are cleaned. It becomes difficult for the natural frequency of the blade 5 to coincide. Therefore, it is possible to make it difficult to generate vibrations that accompany the return from the deformation of the edge portion.

(Aspect B)
In aspect A, a blade including an edge portion of the blade member such as the cleaning blade 5 and adjacent to a blade facing surface such as a blade facing surface 62 facing the contacted member such as the photosensitive member 10 and including the edge portion. The elastic power of the layers other than the edge layer such as the backup layer 7 measured from the blade tip surface side such as the tip surface 63 is 70% or more.
In this aspect, as described in the verification experiment, the settling of the blade can be suppressed by plastic deformation of the backup layer.
If the elastic power of the backup layer is less than 70%, the backup layer is plastically deformed due to the bending stress of the blade, the entire cleaning blade is set, and a cleaning failure occurs due to a decrease in linear pressure.

(Aspect C)
In the aspect A or B, the edge portion of the blade member such as the cleaning blade 5 is included, is adjacent to the blade facing surface such as the blade facing surface 62 facing the contacted member such as the photosensitive member 10, and the edge portion is The elastic work rate of the layer other than the edge layer such as the backup layer 7 measured from the blade front end surface side such as the blade front end surface 63 includes the elastic work of the edge layer such as the edge layer 6 measured from the blade front end side. Or the elastic power of the edge layer measured from the blade facing surface side.

  In this aspect, as described in the above embodiment, even when the thickness of the edge layer 6 is very small compared to the thickness of the backup layer 7, the elastic power of the edge layer 6 is accurately measured. Can do. Therefore, the magnitude relationship between the elastic power of the edge layer 6 and the elastic power of the backup layer 7 can be accurately compared.

(Aspect D)
In any one of the aspects A to C, measurement is performed from the blade facing surface side such as the blade facing surface 62 including the edge portion of the blade member such as the cleaning blade 5 and facing the contacted member such as the photoreceptor 10. The elastic power of the edge layer such as the edge layer 6 or the elastic power of the edge layer measured from the blade tip surface side such as the blade tip surface 63 including the edge portion and adjacent to the blade facing surface. 40% or more.
In this aspect, as described in the verification experiment, it is possible to suppress a cleaning failure due to plastic deformation of the edge portion. When the elastic power of the edge layer is less than 40%, the edge portion is slightly plastically deformed by sliding with the contacted member, and the toner and the toner external additive in the nip between the edge portion and the contacted member The amount of slipping through increases. When the toner and the toner external additive slip through the edge portion, the edge portion is worn and the cleaning function is deteriorated.

(Aspect E)
In any one of the aspects A to D, a lubricant such as the solid protective agent 72 is applied to the surface of the contacted member such as the photoreceptor 10.
In this aspect, as described in the verification experiment, the friction between the cleaning blade and the photosensitive member can be reduced. By reducing this friction, the load applied to the edge portion of the cleaning blade is reduced. Edge wear is suppressed. Accordingly, it is possible to suppress a cleaning failure in a low temperature environment.

(Aspect F)
In any one of the aspects A to C, a lubricant such as the solid protective agent 72 is applied to the surface of the contacted member such as the photoreceptor 10, and the elastic power of the edge layer such as the edge layer 6 is 30. % Or more.
In this aspect, as described in the verification experiment, even when the elastic power of the edge layer is less than 40%, the deterioration of the cleaning function due to the plastic deformation of the edge portion of the cleaning blade can be suppressed. it can. If the elastic power of the edge layer is less than 30%, the rubber property of the material cannot be maintained.

(Aspect G)
In any one of the aspects A to F, a pressure mechanism such as a pressure mechanism 80 that keeps the contact pressure of the blade member such as the cleaning blade 5 with respect to the contact member such as the photoconductor 10 constant is provided.
In this aspect, as described in the verification experiment, the contact pressure becomes a constant value over time, so that the linear pressure does not decrease. Accordingly, it is possible to make it difficult for the cleaning function to decrease due to the decrease in linear pressure.

(Aspect H)
In any one of the aspects A to E, a pressure mechanism such as a pressure mechanism 80 that keeps the contact pressure of the blade member such as the cleaning blade 5 with respect to the contact member such as the photoreceptor 10 constant, The elastic power of layers other than the edge layer such as the backup layer 7 is 50% or more.
In this aspect, as described in the verification experiment, even when the elastic power of the backup layer is less than 70%, it is possible to suppress the cleaning function deterioration due to the decrease in linear pressure over time.

(Aspect I)
In the aspect A, the Martens hardness of the edge layer such as the edge layer 6 is 1.0 [N / mm ² ] or more.
In this aspect, as described in the verification experiment, it is possible to suppress filming in which the toner external additive is fixed to the image carrier.
When the Martens hardness of the edge layer is 1.0 [N / mm ² ] or less, the nip width between the contacted member and the edge portion increases, the contact pressure of the edge portion is dispersed, and the contacted member The sticking material on the surface cannot be scraped off. Further, since the deformation of the edge portion is large, a load is applied to the edge portion, and the edge portion is worn or chipped. Filming occurs due to the dispersion of the contact pressure of the edge portion and the wear and chipping of the edge portion.

(Aspect J)
In aspect I, the Martens hardness of the edge layer such as the edge layer 6 is larger than the Martens hardness of a layer other than the edge layer such as the backup layer 7.
In this aspect, as described in the verification experiment, functional separation between the edge layer and the backup layer can be performed. That is, even when the hardness of the edge layer is high enough to maintain the removal ability of the surface of the contacted member, the backed-up layer has a low hardness that can maintain rubber properties, so that the contacted member The followability of the entire blade with respect to the surface shape can be maintained.

(Aspect K)
In the aspect I or J, the edge portion of the blade member such as the cleaning blade 5 is included and is adjacent to the blade facing surface such as the blade facing surface 62 facing the contacted member such as the photosensitive member 10 and includes the edge portion. The Martens hardness of the edge layer measured from the blade tip surface side, such as the blade tip surface 63, or the Martens hardness of the edge layer measured from the blade facing surface side, such as the backup layer 7 measured from the blade tip surface side, etc. It is larger than the Martens hardness of the layers other than the edge layer.
In this aspect, as described in the above embodiment, the Martens hardness of the edge layer 6 can be accurately measured even when the thickness of the edge layer 6 is very small compared to the thickness of the backup layer 7. it can. Therefore, the magnitude relationship between the Martens hardness of the edge layer 6 and the Martens hardness of the backup layer 7 can be accurately compared.

(Aspect L)
A charging unit such as a charging unit 40 for charging the surface of the image carrier such as the photosensitive member 10; an exposure unit such as an exposure device 140 for exposing the charged image carrier to form an electrostatic latent image; Developing means such as a developing unit 50 that develops an image using toner to form a visible image, transfer means such as an intermediate transfer device 160 that transfers the visible image to a recording medium, and transfer transferred to the recording medium In an image forming apparatus such as a printer 100 having a fixing unit such as a fixing device 30 that fixes an image and a cleaning unit such as a cleaning device 1 that removes toner remaining on the image carrier, the cleaning unit includes modes A to A. The blade member according to any one of the embodiments is used.
In this aspect, it is possible to prevent the settling of the blade as a whole and the generation of abnormal noise due to the vibration of the edge layer in contact with the photoreceptor, which has occurred in the cleaning unit of the image forming apparatus.

(Aspect M)
In the image forming apparatus according to aspect L, the charging unit such as the charging unit 40 applies an AC voltage to the surface of the image carrier such as the photoreceptor 10.
In this aspect, as described in the above embodiment, the charged potential on the surface of the image carrier is stabilized, and high image quality and long life can be achieved.

(Aspect N)
In the image forming apparatus according to aspect L, the image carrier such as the photoreceptor 10 contains inorganic fine particles on the surface.
In this aspect, as described in the above embodiment, it is possible to suppress the wear of the image carrier, and the electrophotographic system can have high image quality, high stability, and high durability.

(Aspect O)
A charging unit such as a charging unit 40 for charging the surface of the image carrier such as the photosensitive member 10; an exposure unit such as an exposure device 140 for exposing the charged image carrier to form an electrostatic latent image; Developing means such as a developing unit 50 that develops an image using toner to form a visible image, transfer means such as an intermediate transfer device 160 that transfers the visible image to a recording medium, and transfer transferred to the recording medium Fixing means such as a fixing device 30 for fixing an image, cleaning means such as a cleaning device 1 for removing toner remaining on the image carrier, and a protective agent applying device for applying a lubricant to the surface of the contacted member In an image forming apparatus such as a printer 100 having a mechanism such as 70, the blade member according to any one of claims 1 to 11 is used as the cleaning unit.

DESCRIPTION OF SYMBOLS 1 Cleaning device 5 Cleaning blade 6 Edge layer 7 Backup layer 10 Photoconductor 30 Fixing device 40 Charging part 50 Developing part 61 Edge part 62 Blade facing surface 63 Blade front end surface 70 Protective agent coating device 72 Solid protective agent 80 Pressure mechanism 100 Printer 140 Exposure device 160 Intermediate transfer device

JP 2013-76970 A

Claims (15)

  In the blade member that abuts the edge portion that is the tip ridge line portion of the elastic blade on the surface of the abutted member, the elastic blade includes an edge layer having the edge portion and at least one layer in which the edge layers are laminated. A blade member, wherein the elastic power of a layer other than the edge layer is larger than the elastic power of the edge layer.   2. The blade member according to claim 1, wherein the blade member includes an edge portion of the blade member and is adjacent to a blade facing surface facing the abutted member, and a layer other than the edge layer measured from the blade tip surface side including the edge portion. A blade member having an elastic power of 70% or more.   3. The blade member according to claim 1, wherein the blade member includes an edge portion of the blade member and is adjacent to a blade-facing surface facing the contacted member, and other than the edge layer measured from the blade tip surface side including the edge portion. The elastic power of the layer is larger than the elastic power of the edge layer measured from the blade tip surface side or the elastic power of the edge layer measured from the blade facing surface side. Blade member.   The blade member according to any one of claims 1 to 3, wherein an elastic power of the edge layer measured from a blade facing surface side including the edge portion of the blade member and facing the contacted member, or the edge portion is determined. And a blade member characterized in that the edge layer has an elastic power of 40% or more measured from the blade tip surface side adjacent to the blade facing surface.   The blade member according to any one of claims 1 to 4, wherein a lubricant is applied to a surface of the contacted member.   4. The blade member according to claim 1, wherein a lubricant is applied to a surface of the contacted member, and the elastic power of the edge layer is 30% or more. 5.   The blade member according to any one of claims 1 to 6, further comprising a pressurizing mechanism that maintains a constant contact pressure of the blade member with respect to the contact member.   6. The blade member according to claim 1, further comprising a pressurizing mechanism that maintains a constant contact pressure of the blade member with respect to the contact member, and an elastic power of a layer other than the edge layer is 50% or more. A blade member characterized by the above. 2. The blade member according to claim 1, wherein the edge layer has a Martens hardness of 1.0 [N / mm ² ] or more.   The blade member according to claim 9, wherein the Martens hardness of the edge layer is larger than the Martens hardness of a layer other than the edge layer.   The blade member according to claim 9 or 10, wherein the edge layer has a martens of the edge layer measured from a blade front surface side adjacent to a blade facing surface that includes the edge portion of the blade member and faces the contacted member. The blade member characterized in that the hardness or the Martens hardness of the edge layer measured from the blade facing surface side is larger than the Martens hardness of a layer other than the edge layer measured from the blade tip surface side.   A charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged image carrier to form an electrostatic latent image, and developing the electrostatic latent image with toner to form a visible image. Image forming apparatus comprising: developing means; transfer means for transferring a visible image to a recording medium; fixing means for fixing the transferred image transferred to the recording medium; and cleaning means for removing toner remaining on the image carrier. 12. An image forming apparatus according to claim 1, wherein the blade member is used as the cleaning unit.   13. The image forming apparatus according to claim 12, wherein the charging unit applies an alternating voltage to the surface of the image carrier.   13. The image forming apparatus according to claim 12, wherein the image carrier contains inorganic fine particles on the surface thereof.   A charging unit for charging the surface of the image carrier, an exposure unit for exposing the charged image carrier to form an electrostatic latent image, and developing the electrostatic latent image with toner to form a visible image. A developing unit; a transferring unit that transfers a visible image onto a recording medium; a fixing unit that fixes the transferred image transferred onto the recording medium; a cleaning unit that removes toner remaining on the image carrier; 12. An image forming apparatus having a mechanism for applying a lubricant to a surface of a contact member, wherein the blade member is used as the cleaning unit.

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