JP2005003718A - Toner restricting member and development device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress fine particles of toner, a post-processing agent or the like from melt-sticking to a toner restricting member and to appropriately restrict the toner conveyed to a development area by a toner carrier for a long time to stably obtain a satisfactory image, in a development device in which the toner restricting member is made to be in contact with the surface of the toner carrier in a certain area of a path along which the toner held on the surface of the toner carrier is conveyed to a development area opposite an image carrier and the amount of toner conveyed to the development area by the toner carrier is restricted by the toner restricting member. <P>SOLUTION: The toner restricting member 15 used in the development device has a relative load length tp of 5% or more when a cut level is 10% in a relative load curve (Abbot's load curve) in the direction in which toner t moves in the contact face of the member 15 and toner carrier 11. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００２８】
この結果から明らかなように、トナー担持体と接触する面におけるトナーの移動方向の相対負荷曲線（アボットの負荷曲線）において、カットレベルが１０％の時の相対負荷長さｔｐが５％以上になったトナー規制部材を使用した実施例１〜４のものにおいては、上記の相対負荷長さｔｐが５％未満になったトナー規制部材を使用した比較例１〜４のものに比べて、トナー規制部材に対する後処理剤等の融着や、得られた画像における筋状の濃度ムラの発生が非常に少なくなり、特に、高温高湿度環境条件においても、後処理剤等がトナー規制部材に融着するのが抑制され、筋状の濃度ムラの発生がない良好な画像が安定して得られるようになった。
【００２９】
【発明の効果】
以上詳述したように、この発明においては、トナーをトナー担持体の表面に保持させて像担持体と対向する現像領域に搬送する途中に、このトナー担持体の表面にトナー規制部材を接触させ、このトナー規制部材によりトナー担持体によって現像領域に搬送されるトナーの量を規制するようにした現像装置において、上記のトナー規制部材として、トナー担持体と接触する面におけるトナーの移動方向の相対負荷曲線（アボットの負荷曲線）において、カットレベルが１０％の時の相対負荷長さｔｐが５％以上になったものを用いるようにしたため、トナーが割れて生じた微粉やトナーに添加させた後処理剤がトナー規制部材に融着するのが抑制されるようになった。
【００３０】
この結果、この発明においては、トナー担持体と接触するトナー規制部材の面に凹凸が生じるのが防止されて、トナー担持体によって現像領域に搬送されるトナーに筋状のムラが生じるのが抑制され、形成される画像に筋状の濃度ムラ等が発生するのが防止されて、良好な画像が安定して得られるようになった。
【図面の簡単な説明】
【図１】この発明の一実施形態に係る現像装置の概略説明図である。
【図２】実施例４及び比較例１において使用したトナー規制部材の表面におけるカットレベル（％）と相対負荷長さｔｐ（％）との関係を示した図である。
【符号の説明】
１１ トナー担持体
１５ トナー規制部材
Ｐ 像担持体
ｔ トナー[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a developing device used for developing a latent image formed on an image carrier in an image forming apparatus such as a copying machine or a printer, and a toner regulating member used for the developing device. While being held on the surface of the toner carrier and transported to the development area facing the image carrier, a toner regulating member is brought into contact with the surface of the toner carrier, and is transported to the development area by the toner carrier by the toner regulating member. In the developing device in which the amount of toner to be regulated is controlled, the toner regulating member is prevented from fusing the toner fine powder or the post-treatment agent applied to the toner, and the toner carrier supports the toner in the development region. This is characterized in that the conveyed toner is appropriately regulated over a long period of time by the toner regulating member, and a good image can be stably obtained.
[0002]
[Prior art]
In an image forming apparatus such as a copying machine or a printer, various developing devices are used to develop a latent image formed on an image carrier. As such a developing device, development including a carrier and toner is used. In addition to the two-component developing type developing device using an agent, a one-component developing type developing device using only toner without using a carrier has been known.
[0003]
In such a one-component development type developing device, generally, the outer peripheral surface of the toner carrying member is held when the toner is held on the outer peripheral surface of the toner carrying member and transported to the developing region facing the image carrier. The toner regulating member is pressed against the toner, the toner regulating member regulates the amount of toner held on the outer peripheral surface of the toner carrier and conveyed to the developing area, and the toner is charged, and thus regulated and charged. The toner is conveyed to the development area by the toner carrier, and the toner is supplied from the toner carrier to the latent image portion of the image carrier for development.
[0004]
However, when the toner regulating member is pressed against the outer peripheral surface of the toner carrying body as described above to regulate the amount of toner conveyed by the toner carrying body, the toner is broken and fine powder is generated. The added post-treatment agent is removed, and the toner fine powder and post-treatment agent thus generated are gradually fused to the surface of the toner regulating member, and the surface of the toner regulating member in contact with the toner carrier is uneven. As a result, streaky unevenness occurs in the toner conveyed to the development area by the toner carrier, and streaky density unevenness occurs in the formed image.
[0005]
In recent years, a resin coating layer containing graphite is provided on each surface where the toner regulating member and the toner carrier are in contact with each other, and the center line average roughness (Ra) on the surface of the toner carrier is set to 0. 0. The center line average roughness (Ra) on the surface of the toner regulating member is set to 0.1 to 2.0 μm so that the toner is appropriately charged, and the toner regulating member has fine toner particles. Have been proposed (for example, see Patent Document 1).
[0006]
However, even when the toner carrier or toner regulating member as described above is used, the toner regulation depends on the uneven state on the surface, for example, whether the tip of the convex part is sharp or smooth. The state in which the toner fine powder and the post-treatment agent adhere to the member is different, and the toner regulation member cannot still sufficiently prevent the toner fine powder and the post-treatment agent from fusing to the toner regulating member. There is a problem that streaky unevenness occurs in the toner conveyed to the developing region, and streaky density unevenness occurs in the formed image.
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 6-186838
[Problems to be solved by the invention]
In the present invention, while the toner is held on the surface of the toner carrier and conveyed to the development area facing the image carrier, a toner regulating member is brought into contact with the surface of the toner carrier, and the development area is formed by the toner carrier. In the developing device in which the amount of toner conveyed to the toner is regulated by the toner regulating member, the toner regulating member is prevented from adhering and fusing the toner fine powder, the toner post-treatment agent, etc. An object of the present invention is to appropriately regulate the toner conveyed to the developing region by the body over a long period of time and stably obtain a good image.
[0009]
[Means for Solving the Problems]
In the present invention, in order to solve the above-described problems, the toner regulating member is placed on the surface of the toner carrier while the toner is held on the surface of the toner carrier and is transported to the developing region facing the image carrier. In the developing device in which the amount of toner conveyed to the developing region by the toner carrier is regulated by the toner regulating member, the toner movement on the surface in contact with the toner carrier as the toner regulating member In the relative load curve in the direction (Abbott load curve), the relative load length tp when the cut level is 10% is 5% or more.
[0010]
Thus, in the relative load curve (Abbott load curve) in the toner moving direction on the surface in contact with the toner carrier, the relative load length tp when the cut level is 10% is 5% or more. When the regulating member is used, the extreme convex portions in the shallow area where the cut level is in contact with the toner conveyed by the toner carrier are reduced, and the fine powder generated by the cracking of the toner and the post-treatment agent added to the toner are regulated by the toner. Fusing to the member is suppressed.
[0011]
As a result, it is possible to prevent unevenness on the surface of the toner regulating member that comes into contact with the toner carrying member, and to suppress the occurrence of streaky unevenness in the toner conveyed to the developing region by the toner carrying member. By suppressing the toner charging unevenness in the image, the occurrence of streaky density unevenness in the formed image is prevented, and a good image can be stably obtained.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A developing device according to an embodiment of the present invention will be specifically described below with reference to the accompanying drawings.
[0013]
In the developing device in this embodiment, as shown in FIG. 1, the toner carrier 11 that holds the toner t on the surface and guides the toner t to the development area facing the image carrier P is separated from the image carrier P via a required interval. A partition member 12 having an opening 12a in the apparatus main body 10 and a toner container 10a for storing the toner t, and a toner supply unit for supplying the toner t to the toner carrier 11 10b.
[0014]
Here, in the toner accommodating portion 10a, a toner conveying member 13 having a flexible blade member 13a at the tip is rotatably provided, and the blade conveying member 13a is rotated to rotate the blade member 13a. Thus, the toner t stored in the toner storage unit 10a is supplied to the toner supply unit 10b through the opening 12a.
[0015]
In the toner supply unit 10b to which the toner t is supplied in this way, the toner supply roller 14 is provided so as to press against the toner carrier 11, and the toner supply roller 14 and the toner carrier 11 are arranged in the same direction. The toner t is supplied to the surface of the toner carrier 11 from the toner supply roller 14, and the toner t supplied in this way is conveyed by the toner carrier 11 to the development area facing the image carrier P. I try to let them.
[0016]
Then, while the toner t is transported to the developing area facing the image carrier P by the toner carrier 11, a plate-like toner regulating member 15 is brought into pressure contact with the surface of the toner carrier 11. The toner regulating member 15 regulates the amount of toner t conveyed to the development area and charges the toner t.
[0017]
Then, the toner t regulated and charged by the toner regulating member 15 is transported to the developing region facing the image carrier P by the toner carrier 11, and a development bias power source (not shown) is supplied to the toner carrier 11. The developing bias voltage is applied to the electrostatic latent image portion formed on the image carrier P, and the toner t is supplied from the toner carrier 11 for development.
[0018]
Here, in the developing device according to this embodiment, as the toner regulating member 15, the relative load curve (in the moving direction of the toner t on the surface in contact with the toner carrier 11, that is, the rotational direction of the toner carrier 11 ( In the Abbott load curve), a load with a relative load length tp of 5% or more when the cut level is 10% is used.
[0019]
When such a toner restricting member 15 is used, the toner t is prevented from fusing fine powder and post-treatment agent on the surface of the toner restricting member 15, and the toner conveyed to the developing region by the toner carrier 11. t is stably regulated by the toner regulating member 15, and the toner carrier 11 suppresses the occurrence of streak-like unevenness in the toner t conveyed to the developing region, and streaks are formed in the formed image. It is possible to prevent the occurrence of density unevenness.
[0020]
In the developing device of this embodiment, the toner carrier 11 is provided so as to face the image carrier P with a required interval as described above, but the toner carrier 11 is in contact with the image carrier P. It is also possible to provide it.
[0021]
Next, in the relative load curve in the moving direction of the toner t on the surface in contact with the toner carrier 11 as described above (Abbott load curve), the relative load length tp when the cut level is 10% is 5% or more. When the toner regulating member 15 is used, the toner t fine powder and the post-treatment agent are prevented from adhering to and fusing to the surface of the toner regulating member 15, and streaky density unevenness is formed in the formed image. It will be clarified with examples and comparative examples that the occurrence of this is prevented.
[0022]
(Examples 1-4 and Comparative Examples 1-4)
In Examples 1 to 4 and Comparative Examples 1 to 4, a commercially available printer (manufactured by Minolta: magiccolor 2300) was used, and the surfaces of toner regulating members made of SUS plates used in the developing device of this printer were respectively By impregnating a metal abrasive (manufactured by Nippon Abrasive Industry Co., Ltd .: Picard Metal Polishing) with a waste cloth and pressing it against the surface of the toner regulating member, the rubbing is changed several to several tens of times in the toner feed direction The toner regulating members that have been polished and thus polished by changing the number of times of rubbing are respectively used in the developing device of the printer. The toner regulating member used in Comparative Example 2 was not polished as described above.
[0023]
Here, the surface state of each toner regulating member polished as described above was measured using a commercially available roughness measuring device (manufactured by Tokyo Seimitsu Co., Ltd .: Surfcom 1400), and Examples 1 to 4 and Comparative Examples 1 to 4 were measured. For each toner regulating member, relative load length tp (%) when the cut level is 10% in the relative load curve (Abbott load curve) in the toner movement direction on the surface in contact with the toner carrier, arithmetic average The roughness Ra (μm), the maximum roughness Rmax (μm), the ten-point average roughness Rz (μm), and the average interval Sm (μm) of the irregularities were determined, and the results are shown in Table 1 below. For the toner regulating members used in Example 4 and Comparative Example 1, the relationship between the cut level (%) and the relative load length tp (%) is shown in FIG.
[0024]
Each of the toner regulating members polished as described above is used in the developing device of the printer, and each printer is used to obtain a high temperature and high humidity environment condition (H / H) of 30 ° C. and 85% humidity. In a low temperature and low humidity environment condition (L / L) with a temperature of 10 ° C. and a humidity of 15%, a continuous printing test of 5000 sheets was performed at a system speed of 100 mm / s, respectively, and the surface condition of each toner regulating member and after printing The image evaluation was performed and the results are shown in Table 1 below.
[0025]
Here, regarding the surface state of the toner regulating member, each toner regulating member after the printing durability test is taken out, the surface of each toner regulating member is air-cleaned, the surface of each toner regulating member is visually observed, and post-processing is performed. ◯ when no adhesion of the agent or the like is observed, △ when the adhesion of the post-treatment agent or the like is partially recognized, and when the post-treatment agent or the like is observed over the entire portion in contact with the toner carrier Is indicated by ×.
[0026]
As for image evaluation, a half (2 × 2) image is formed after the above-mentioned printing durability, and stripe-like density unevenness in the obtained image is examined. The case where slight streaky density unevenness occurred was indicated by Δ, and the case where streak density unevenness was clearly recognized was indicated by x.
[0027]
[Table 1]

[0028]
As is apparent from this result, in the relative load curve (Abbott load curve) in the toner moving direction on the surface in contact with the toner carrier, the relative load length tp when the cut level is 10% is 5% or more. In Examples 1 to 4 using the toner regulating member thus formed, the toner is compared with those in Comparative Examples 1 to 4 using the toner regulating member in which the relative load length tp is less than 5%. The adhesion of the post-processing agent to the regulating member and the occurrence of streaky density unevenness in the obtained image are extremely reduced. In particular, the post-processing agent is fused to the toner regulating member even under high temperature and high humidity environment conditions. It is possible to stably obtain a good image that is suppressed from wearing and has no streak-like density unevenness.
[0029]
【The invention's effect】
As described above in detail, according to the present invention, the toner regulating member is brought into contact with the surface of the toner carrier while the toner is held on the surface of the toner carrier and conveyed to the developing area facing the image carrier. In the developing device in which the amount of toner conveyed to the developing region by the toner carrier is regulated by the toner regulating member, as the toner regulating member, relative to the toner moving direction on the surface in contact with the toner carrier. Since the load curve (Abbott load curve) has a relative load length tp of 5% or more when the cut level is 10%, it is added to the fine powder or toner generated by cracking the toner. The post-processing agent is prevented from being fused to the toner regulating member.
[0030]
As a result, in the present invention, the surface of the toner regulating member that contacts the toner carrier is prevented from being uneven, and the toner conveyed to the development area by the toner carrier is prevented from causing streaky irregularities. As a result, the occurrence of streaky density unevenness in the formed image is prevented, and a good image can be stably obtained.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory diagram of a developing device according to an embodiment of the present invention.
FIG. 2 is a graph showing the relationship between the cut level (%) on the surface of the toner regulating member used in Example 4 and Comparative Example 1 and the relative load length tp (%).
[Explanation of symbols]
11 Toner carrier 15 Toner regulating member P Image carrier t Toner

Claims (2)

In a toner regulating member that regulates the amount of toner conveyed by the toner carrier by contacting the surface of the toner carrier that holds the toner, a relative load curve (Abbott in the moving direction of the toner on the surface that contacts the toner carrier In the load curve, the relative load length tp when the cut level is 10% is 5% or more. While the toner is held on the surface of the toner carrying member and conveyed to the developing region facing the image carrying member, a toner regulating member is brought into contact with the surface of the toner carrying member, and the developing region is developed by the toner carrying member by the toner regulating member. In a developing device that regulates the amount of toner conveyed to the developing device, the toner regulating member according to claim 1 is used as the toner regulating member.

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