JPS62191868A - Formation of developer layer - Google Patents

Abstract

PURPOSE:To obtain a developer layer having a desired thickness by pressing an elastic plate to a developer carrying body surface and slipping the developer through the space corresponding to the thickness equal to the grain size of the magnetic carrier of the developer between the elastic plate and the developer carrying body surface. CONSTITUTION:A nonmagnetic cylinder is used for the developer carrying body 103 and the elastic plate 105 having a flat surface is pressed to the carrying body 103 surface. The developer D held by the magnetic field generated by the magnet of the carrying body 103 is slipped out of the space between the carrying body 103 and the elastic plate 105 and is carried to a developing region when the carrying body 103 is moved in a prescribed direction. The relation between the space between the elastic plate 105 and the carrying body 103 and the linear pressure is constant over a wide range at the time of the space corresponding to the grains size of the carrier and therefore, the conveying rate of the developer can be so controlled as to allow the passage of every one piece of the carriers in the contact position of a sleeve 3 by setting the linear pressure between the elastic plate and the carrying body within said range. The formation of the extremely thin developer layer is thus made possible, by which the developing space can be made small and since the electric field is sufficiently large, the image quality such as resolving power and gradation reproducibility of the image to be developed is remarkably improved.

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to an image forming body, an image plate 5 used for electrophotography, etc.
A developing means for developing a latent image on a developer, which regulates the /f4 thickness of the developer held and conveyed on the developer carrier.

[Regarding improvements in the method of forming ri. [Background of the invention]

In the electrophotographic method in which the e-electrolayer image on the image forming body is visualized by development to form the final image, there are currently two types of development methods: one using a two-component developer, and the other using a two-component developer consisting of a magnetic carrier and a non-magnetic toner. There are two main types of development methods: However, even in the development method using a -component type developer, in the development method using a -component non-magnetic developer, the force for supporting the developer on the developer carrier is due to the electric charge of the developer. Only Coulomb force and van der Waalska are used, and it is difficult to form a stable and uniform developer layer. Mar
In the developing method using this one-component magnetic developer, since the toner generally contains a magnetic substance such as black magnetite powder, it is difficult to obtain toner with vivid colors other than black. On the other hand, a developing method using a two-component developer has advantages over other developing methods in that it forms a stable developer layer and can use brightly colored toners. Generally, when a latent image on an image forming body is developed using a developer held and conveyed on a developer carrier, the distance between the latent image carrier and the developer carrier is required to increase the contrast of the resulting image. By reducing the size of the image, the image quality can be improved. If the gap between the image carrier and the developer carrier is made small, in the contact development method in which development is carried out by bringing the image carrier and the developer layer into contact, the developer can be The amount of developer held and conveyed by the developer carrier must be kept within an appropriate range to prevent the latent image and developed image from being compacted and the resulting pressure destroying the latent image or developed image. be. The “developer amount” mentioned here is
This is the weight of the developer per unit area held on the surface of the developer carrier. In addition, even in a non-contact development method in which development is performed while keeping the image carrier and the developer layer in a non-contact state, when the gap between the image carrier and the developer layer is made small, the gap between the image carrier and the developer layer is reduced. It is necessary to reduce the amount of developer on the developer carrier to keep it within an appropriate range so that ~ does not come into contact with it. In the conventional developing method using a two-component developer, for example, development has been carried out using a developing device having the following configuration. A non-magnetic cylindrical member or a non-magnetic belt is used as the developer-carrying member, and the magnets are placed in a fixed position on the developer-carrying surface. Even if the arrangement is variable, such as rotating around a certain axis, it is sufficient to use one that is suitable for the development conditions. Of the developer on the developer carrying surface, the magnetic carrier is placed on the opposite side of the developer carrying surface. receives force from the magnetic field of the magnet,
Depending on the magnetic force of the magnet and the magnetic properties of the carrier, the carrier stands up in the form of spikes and is held on the developer carrying surface. When the non-magnetic toner is stirred in the developer container, it is frictionally charged with the magnetic carrier, and the non-magnetic toner and the magnetic carrier have charges of opposite polarity and are bound to each other by Coulomb force. Since the magnetic carrier is held on the developer carrying surface by the magnetic field of the magnet, the non-magnetic toner is also held on the developer carrying surface together with the magnetic carrier. A developer layer made of non-magnetic toner is formed. This developer layer is held and transported on the developer carrying surface,
Developing the latent image on the image carrier. As mentioned above, this developer layer is at least compacted in the gap between the image carrier and the developer I, and the developer I should not come into contact with the image carrier, which should be kept non-contact. The following conditions must be met. Furthermore, (1) the phenomenon of "scattering" in which toner adheres to the surface of the image carrier other than the image area does not occur. ■ The phenomenon of "carrier adhesion" in which carriers adhere to the surface of the image carrier does not occur. ■ Enough toner adheres to the latent image area to provide sufficient image density. ■ RF with enough gradation to reproduce the gradation of the latent image
The toner image is retained. The developer layer must satisfy the following conditions. In order to satisfy these conditions ('1), the physical properties of the developer itself, its stirring method, (a) the physical properties of the image carrier, the speed of the phase between the latent image carrier and the developer JVr, and the latent image carrier. The means for forming a latent image on the body, the electrical bias applied between the image carrier and the developer carrier, the magnetic force of the magnet, the shape of the magnetic field, etc. must also be within appropriate ranges. Such conditions include the amount of developer on the surface of the developer carrier and the thickness of the developer layer, and the appropriate range is even smaller than the above-mentioned minimum conditions. Conventionally, in order to make the developer layer held on the surface of the developer carrier a desired amount of developer and developer N1, a layer made of metal or wood 11'ff as shown in FIG. 20 was used. The thickness regulating plate 205 is disposed close to the surface of the developer carrier 203, and the developer layer is held on the surface of the developer carrier 203 and moves, so that the layer thickness regulating plate 205 and the surface of the developer carrier 203 are moved. It was configured to slip through the gap and be transported to the development area. The developer carrier 203 illustrated here is a magnet 20
The case is shown in which a non-magnetic cylinder with a built-in magnet 4 is used. By a method using such an MFI regulation plate 205,
In order to make the layer thickness of the developer layer 1+o+n or less, the layer thickness regulating plate 205 and the developer carrier 203 are
The gap between the surfaces must be around 0.5+n+n or less. This is the developer layer thickness regulating plate 205.
When passing through the gap between the developer carrier 203 and the developer carrier 203, the developer is pushed in and becomes a high-density developer layer.
After passing through the gap between the WJ thickness regulating plate 205 and the developer carrier 203, the developer on the surface of the developer carrier 203 is
The developer layer rises due to the magnetic force of the magnet 204 and becomes a low-density developer layer, which is 1.5 to
This is because it will be three times as tall. Ordinary copiers and printers that develop and visualize latent images of streetcars have an image width of several hundred millimeters. In order to set the above-mentioned gap between the layer thickness regulating plate and the developer carrier surface to around 0.5to +n or less, and to set this uniformly and stably over the entire image width, high-precision processing of the layer thickness regulating plate is required. This requires highly accurate adjustment and is not easy to implement. [Problem to be Solved by the Invention, α] The present invention uses a developer containing a magnetic carrier and a non-magnetic toner that can use a vivid color toner and form a stable developer layer. To provide a method for forming a developer layer capable of obtaining a high-quality image by stably and uniformly forming a thin developer M in which a developer carrying member and a developer carrying member can be brought closer to each other than in the past. With the goal. [1000 tons to solve the problem] The above purpose is to make the gap between the layer thickness regulating means and the developer carrier thick enough to approximate the particle size of the magnetic carrier of the developer containing the magnetic carrier and toner. This is achieved by a method for forming a developer layer, characterized in that the developer layer is formed and held by passing the developer i'IiI through the gap. [Function] In the present invention, a desired developer layer is obtained by pressing an elastic plate against the surface of the developer carrier and allowing the developer to pass between the elastic plate and the surface of the developer carrier. This is a method of forming a developer layer that utilizes the fact that when the developer slips through, the contact state between the developer carrier and the elastic plate is released by a thickness corresponding to the particle size of the magnetic carrier of the developer. FIG. tp11 shows an example of the layer thickness regulating means of the present invention. The elastic plate is pressed against the developer carrier surface with the tip of the elastic plate facing upstream of the developer carrier surface. Then, as shown in the figure, when a non-magnetic cylinder is used as the developer carrier 103 and a flat elastic plate 105 is pressed against the surface of the developer carrier 103, a wedge-shaped portion is formed between the tip of the elastic plate 105 and the pressed contact point. A space 110 is created. This situation f! developer carrier 1
03 in a predetermined direction, the developer carrier 103
Some of the developer particles held by the magnetic field of the magnets enter the wedge-shaped space 110, while others do not enter the wedge-shaped space 110 and fall onto the surface of the elastic plate 105 opposite to the developer carrier 103. Of these, only the developer that has entered the wedge-shaped space 110 is
Due to the frictional force with the developer carrier 103, the developer passes between the developer carrier 103 and the elastic plate 105 and is carried to the development area. At this time, the developer carrier 103 and the elastic plate 10
The amount of developer that passes through the wedge-shaped space 110
The height of the opening of the elastic plate 105 and the height of the opening of the developer carrier 10
It is determined by the linear pressure applied to 3. This, of course, applies when the conditions mentioned above, such as the physical properties of the developer, the stirring method, the magnetic field and force of the magnet, etc., are fixed. The developer that has entered the wedge-shaped space 110 from the opening of the wedge-shaped space RLV1110 is caused by the magnetic carrier.
Frictional force between the magnetic carrier and the developer carrier 103 caused by the magnetic carrier being pressed against the developer carrier 103 by a magnetic field provided on the back side of the developer carrier 103;
Under the pressure of the developer particles that successively rush into the wedge-shaped spaces 110, the developer particles are pushed in the direction in which the wedge-shaped spaces 110 are constricted. The pushed developer pushes up the elastic plate 105 and passes between the elastic plate 105 and the developer carrier 103. When the gap distance between the elastic plate 105 and the developer carrier 103 is larger than one carrier in the area where the developer material slips through, the elastic plate XC) 5 is supported by the developer trying to push in from behind. The component of the force in the direction perpendicular to the elastic plate 105 and the force that causes the carrier to rise along the magnetic field caused by the magnet (on the other hand, the gap distance between the elastic plate 105 and the developer carrier 103 is the carrier) When the particle size of the carrier becomes equivalent to the particle size of the individual particles, the strength of the carrier will support the elastic plate 105.
In order to scrape, it is necessary to prevent the developer from entering between the elastic plate 105 and the developer carrier 103, but it is necessary to apply enough linear pressure to destroy the carrier itself. It won't happen. Elastic plate 105 and developer carrier 103
The relationship between the gap distance and linear pressure is as shown in FIG. In other words, the elastic plate 105 and the developer carrier 1.0
The gap distance between the elastic plate 105 and the developer carrier 103 is constant over a wide range of linear pressure between the elastic plate 105 and the developer carrier 103, and the setting of the elastic plate 105 becomes easy. . It can be confirmed as follows that the gap distance between the elastic plate 105 and the developer carrier 103 is equal to one carrier particle diameter. Commercially available dialage (minimum 1) i
0.01 to 0.0O1iz) on the developer carrier]
The difference is that the elastic material is in contact with the developer carrier, which is pressed against the developer carrier without any adhesion.
Fix the probe in contact with flll+. When the developer carrier is moved from this state in a predetermined direction (the direction opposite to the tip of the elastic plate), the carrier enters the wedge-shaped space and lifts the elastic plate. Then, the probe of the dialage is lifted by this lifting movement, and the distance lifted at this time becomes the gap of 1 inch between the elastic plate and the developer carrier. The fact that the thickness of the developer layer is closely related to the particle size of the carrier means that the developer layer is formed of carrier particles in a single layer in terms of '-X quality, as shown in Figure 21 and Figure rXfJ22. The average particle size of the carrier particles used after classification is d
In the current, normal carrier manufacturing method, the carrier particle size has a distribution, ranging from 0.5 times the average particle size to 2 times the average particle size.
There are quite a number of chiarias that are twice the size of the carrier particles, and there are also a few that are smaller and larger than this, so the distance ε between the elastic plate and the developer carrier measured by the above measurement method is It means that. Figure 21 shows that when the variation in chiaria particle size is small, f:
The tS22 diagram shows a case where there is large variation in chiaria particle size. The present invention reduces the linear pressure between the elastic plate and the developer carrier by tjS4.
By setting it to 8-B open in the figure, the carrier becomes one layer of the developer layer and presses it against the developer carrier of the elastic plate.
This is intended to widen the allowable setting range of a pressure. Even if the distance between the elastic plate and the developer carrier is constant, if the height of the f-10 part of the wedge-shaped space at the tip differs, the amount of developer that rushes into the opening of the wedge-shaped space will change. The pressure to push the developer changes, so the wedge-shaped space opens 1]
Although the height of the line between A and 8 must be controlled, its influence is much smaller than when the line pressure is smaller than 8 as shown in the I:tS4 diagram. In the region of linear pressure smaller than 8, the gap distance between the elastic plate and the developer carrier changes due to the change in the force pushing up the elastic plate due to the change in the height of the opening of the wedge-shaped space, and the gap distance between the elastic plate and the developer carrier changes. Against, eight-
0, the pressure between the elastic plate and the developer carrier is supported by the strength of the carrier between the elastic plate and the developer carrier, and the force that pushes the developer into the wedge-shaped space is perpendicular to the elastic plate. This is because the directional component is sufficiently small compared to the pressure in this region. However, even if the gap distance between the elastic plate and the developer carrier is kept constant at one carrier particle diameter, if the amount of developer that enters the wedge-shaped space is too small, the amount of developer that slips through will be reduced accordingly. It becomes less. This is IJI of wedge-shaped space
This is a case where the height of the J0 section is too small. FIG. 5 shows these relationships confirmed through experiments. The horizontal axis represents the length l of the tip of the elastic plate 105 shown in the enlarged view of the main part in FIG. 2, and the vertical axis represents the amount of developer on the developer carrier. , the linear pressure between the elastic plate and the developer layer carrier is changed. p on the horizontal axis is h=
According to n−r+ε, the height of the opening of the wedge-shaped space is 1
It is possible to convert it to 1. In this experiment, a φ18 non-magnetic cylinder with built-in 8-pole 700C1 Iuss magnet roll was used as the developer carrier, and the elastic plate had a thickness of 0.1 mm. A phosphor bronze plate with a WR1 free length of 1M was used. The developer was a mixture of a coating carrier having a particle size of 30 μm and a layer of toner having a particle size of 10 μm in an ffl Jfi ratio of 4:1. Magnet roll rotation speed is 531rp
+a to rotate in the opposite direction to the non-magnetic cylinder. The non-magnetic cylinder is rotated at I 80 r p +n. If the height 11 of the opening of the wedge-shaped space is small, that is, the length of the tip of the elastic plate 105! It can be seen that when is small, the amount of developer that enters the wedge-shaped space is small, and even after passing between the elastic plate and the developer carrier, the amount of developer on the developer carrier is small. In addition, when the height of the opening becomes larger than a certain level, the slipping becomes difficult because the main factor that determines the amount of developer that slips through is that the gap between the openings is constant and is equal to the distance corresponding to the particle size of one carrier. It becomes constant. In addition, the linear pressure between the elastic plate and the developer carrier is 1 g/dead shoulder and 3
There is a slight difference in H/ x a, but 6g/ax and 3g
/zz is almost non-existent. From this, in this experiment, the linear pressure in Figure 4 is 0.5 to 1 g/xz
It can be seen that it is near. However, for the linear pressure port, 6g
All I know is that it is greater than /11N, but if the linear pressure is too large, a large force will be applied to the carrier and toner sandwiched between the developer carrier and the elastic plate, causing crushing, cutting, and melting of the carrier and toner. During development, fine particles of carrier or toner are formed that cause curvature or carrier adhesion, or these fine powders stick to the elastic plate or developer carrier. Furthermore, many disadvantages occur, such as the elastic plate and the developer carrier being worn out due to friction with the carrier and toner, and the elastic plate being permanently deformed. Furthermore, there is a member (
For example, the load placed on the developer container casing also increases, leading to an increase in the size and weight of the developer. Eliminate these problems or bring them to a level where there are no practical problems. What became clear within the scope of this experiment was that the height of the opening of the wedge-shaped space was 0.08 to 0.3 debris, the amount of play was 1 to 3 debris, and the elastic plate and developer carrier The linear pressure is 0.5~6
The amount of developer that slips between the shoulders is 3 to 4 g/c.
It can be seen that the temperature is kept almost constant. The formation of the developer layer according to the present invention has the features of a wide setting tolerance, easy assembly and adjustment, and high reliability. The developer used here was Chiaria with a particle size of 30 uv, which is a ferrite core coated with styrene acrylic, 45 parts by weight of polystyrene, 44 parts by weight of polymethyl methacrylate, and 5 ffl of carbon black IO.
A toner obtained by kneading 1 part of 'f to a particle size of 10 μm was mixed in a weight ratio of 9:1. Next, the material, thickness, and free length of the elastic plate will be described. The requirements of the present invention are the pushing pressure between the elastic plate and the developer carrier, and the height of the opening of the wedge-shaped space between the elastic plate and the tip. The pushing pressure [: can be written as the following equation using the variables in the explanatory diagram shown in ttS3 diagram. E is the elastic modulus of the elastic plate, for example, phosphor bronze = 11200 and Bif/waste shoulder 2 stainless steel =
20000kHzr/i+z'. This is elastic board 1!
It is only 7. As θ becomes larger, equation 111j no longer holds true, but with respect to L, arc PQ (fixing one end of the elastic plate,
If the sword is added to one point of the free part, the elastic plate between them becomes an arc with radius R) is sufficiently good, so this is a fairly good approximation. The pushing pressure F can be set to any value by appropriately selecting the elastic plate (Ell) and the pushing position (θ, PQ) depending on the developer carrier used (cylindrical in this example). You can choose. However, as mentioned above, the pushing pressure F is 11+f.
It is necessary that the value be between 0.5y/zz and 10y/z, and if a certain variable is selected to be too large or too small, the allowable range of the plate's variable will become smaller and the assembly adjustment and processing will be expensive. Accuracy is required. The smaller E, r, and θ are, and the larger the arc I'Q is, the larger the allowable setting range of each of the other variables will be. However, these variables are subject to constraints not only on the set value of F but also on other conditions. When the elastic plate is pressed against the developer carrier 113 in the positional relationship shown in FIG. There is no exchange of developer within and outside the range, resulting in a decrease in toner density, which has an adverse effect on the image. If the developer carrier is cylindrical! As shown in Fig. 56, Fig. 7, and Fig. 8, the elastic plate is placed on the line where the radius rotated by ψ from the vertical line drawn from the center of the cylinder toward the developer container intersects with the outer circumference of the cylinder. When pressed against the body, ψ needs to be at an angular position of 30' or more, preferably 60° or more. Further, as shown in FIG. 8, when the developer container is pressed against the developer carrier 133 at a position just above the upper surface of the developer or at a position above the upper surface of the developer, the elasticity Fj,
The developer is not sufficiently supplied between +35 and the developer carrier 133, and a uniform and stable developer layer cannot be formed. It is necessary to set the depth of the top surface of the developer in the container at a depth of 2zx or more, preferably at a depth of 5cm or more.
．． Reference numerals 127 and 137 indicate stirring members for stirring the developer in each developer container. In this way, IIγ presses the elastic plate against the developer carrier.
There are restrictions on the location, there are restrictions on the size of the developer σ container, and there are also restrictions on the arc PQ. In order to make the developer container 2 as small as possible, it is desirable to have the same height as the developer carrier, so in order to ignite the arc PQ shown in FIG. 3, an elastic plate as shown in FIG. The developer must be placed at an angle, but this has an adverse effect on the circulation of the developer, as described in Section 1 above. Therefore, the arc IIQ should be set to 0.5r≦PQ≦2r, preferably 0.7r≦PQ≦1.5, where the radius of the developer carrier is “0.5r≦PQ≦2r”. The conditions are different when the carrier has a cylindrical shape. For example, when a belt-shaped developer carrier 143 is used as shown in FIG. 9, the conditions are different. This is a unique value, and the larger the value, the greater the force required to cause the same deformation.Therefore, the smaller the elastic coefficient E of the elastic plate, the smaller the change in pressing pressure 1゛ for the same amount of deformation. , pressing pressure F
In order to keep the value within a certain range, the tolerance range for other variables becomes larger. Furthermore, the smaller the thickness t of the elastic plate is to the same extent as the elastic modulus E, the larger the allowable range of the pond variable. In particular, since F is expressed as the third power, its selection is extremely important. E as an elastic plate is 10000kHzr/z
If z2 is used, when PQ=10 and t=o, l, the pushing pressure will be 1 to 10 g/z for scraps, and the display in Figure 3 will be S1.to, 6 to 5.6R scraps. becomes.E is 200
00kgf/assuming everything else is the same, S is 0.3 to 3
．． If L = 0.2zz and other values are the same as in the first example, S will have a shoulder of 0.08 to 0.75 degrees, and the allowable setting range will be narrow. If you thinly r,
It becomes weak against external forces, requires careful handling, and becomes difficult to walk. For the above reasons, the elastic modulus E is 5,000 to 25,000 to 25,000 to 0.03 to 0.2, preferably E is 7,000 to 2.
2000 and/xi', L is 0.05~0, 15z, w
An elastic plate of 1 is suitable for this method. Preferred materials for the elastic plate include phosphorus, copper, brass, steel, stainless steel, etc. In conventional developer layer forming means, as shown in FIG. passes through 'C' and becomes stuck in the opening between the developer layer forming member and the developer carrier,
The method according to the present invention prevents the developer from passing through later, and is likely to accumulate in the gap. f) As shown in Figure 1, the elastic plate is easily deformed, so when a foreign object smaller than the height of the opening of the wedge-shaped space enters,
Even if the 5"4 object is larger than the normal gap between the elastic plate and the developer carrier (effectively one layer of the developer carrier), the elastic plate will be lifted only in that area, allowing the foreign object to slip through and close the opening. For foreign objects larger than the height, since the elastic plate is thin, it cannot stay near the tip of the elastic plate, so it passes through the surface of the elastic plate opposite to the developer carrier and returns to the developer container. .The 5"4 objects mentioned here are metal pieces, 0 (
These include impurities such as fat powder and paper powder, and developer agglomerates. In addition, for development using a -component developer, a method has been proposed in which an elastic plate is pressed against a developer carrier (for example, Japanese Patent Publication No. 59-35018), but according to the present invention, the developer is Because it contains Chiaria, which has a large particle size and high hardness, the sticking of the developer that would have occurred on the elastic plate and developer carrier due to the - component is removed by the abrasion action of ChiTria, and the elastic plate and developer are removed. It has the effect of dramatically improving the life of the carrier. Next, the configuration of a developing device using this developer layer forming method will be described. Here, a non-magnetic cylindrical developer-carrying book is used, but it may also be belt-shaped, flat-shaped, or the like. Depending on the shape of the developer carrier, a wedge-shaped space of a predetermined size may be created in the protruding portion when the elastic body is pressed against it. Additionally, a rotating magnet/trol is built inside the cylinder, but a fixed magnet may be used depending on the development conditions. This developer forming method can also be applied to contact development and regular development. FIG. 16 shows a sectional view of a developing device suitable for applying the developer layer forming method of the present invention. In the figure, 1 is an image forming body, 2 is a housing, 3 is a sleeve, 4 is 14. S is a magnetic roll on the right side of each of the four poles, 5 is a layer forming member, 6 is a fixing member for this member, M is a first stirring member, and 8 is a second stirring member. 9 and 10 are rotation shafts of the stirring members 7 and 8, 11 is a replenishment toner container, 12 is a toner replenishment roller, 13 is a developer reservoir, 14 is a development bias power source, 15 is a development area, ] is a toner, and D is a development area. Represents developer. In such a developing device, the developer reservoir in the developer reservoir 13 rotates in the direction of the arrow m.
The I R member 7 and the second stirring member 8 which rotate in the opposite direction so as to overlap with each other are sufficiently stirred and mixed to form the sleeve 3 which rotates in the direction of the arrow and the magnetic roll 4 which rotates in the opposite direction. Due to the conveying force of the sleeve 3
It adheres to the surface and is transported. The thin layer forming member 5 held by a fixing member 6 extending from the housing 2 is pressed onto the surface of the sleeve 3 at a surface near the end,
The layer thickness of the developer transported as described above is regulated. This developer layer separates the gap and develops the latent image on the image forming member rotating in the direction of the arrow in a non-contact manner during development 'vff IJi+ 5, thereby forming a toner image. Development 1: For kI, a developing bias containing a DC component and an AC component that is comparable to the potential of the non-exposed portion of the image forming body is applied to the sleeve 3 from the voltage 11i 214, and as a result, the sleeve 3
Only the toner in the upper developer is selectively transferred and deposited on the surface of the latent image. Note that the layer thickness of the developer can be measured, for example, as follows. That is, using a Nippon Profile Pronoector manufactured by Nippon Kogaku Co., Ltd., the layer j7 is determined by comparing the position of the projected image of the screen on the sleeve with the projected image of the state in which a thin layer is formed on the sleeve. The J4 layer forming material 5 is made of, for example, a magnetic or non-magnetic metal, with one end fixed by a fixing member G and imparted with elasticity.
It is an extremely uniformly formed thin plate made of metal compounds, plastics, rubber, etc., and its thickness is 10 to 500 μm.
[It is considered to be Q. As mentioned above-- Elastically press the sleeve 3 with the used part on the north end of the thin layer forming member whose end is fixed, and apply the screws one by one to the contact position of the thin plate of the sleeve 3. The amount of developer conveyed is regulated by allowing the developer to pass through. Impurities in the developer and aggregates of the developer and/or toner cannot pass through the regulation position. Therefore, the development area 15
A uniform and stable developer layer can be obtained by changing the Tg layer to -7. Note that the amount of developer transported to the developing area 15 is controlled by changing the pressing force and the contact position of the Tg layer forming member 5 with respect to the sleeve 3, as described above. As mentioned above, it is said that it is advantageous for the carrier and toner constituting the developer to have small particle diameters from the viewpoint of image quality resolution and gradation reproducibility. Even when the particle size is small, by using a means such as the layer forming member 5 described above, it is possible to automatically eliminate impurities, particle agglomerates, etc. in the developer and form a uniform thin layer.Moreover, mJ When the carrier has a particle size as small as that of the toner, the contamination of impurities is eliminated and a uniform thin layer is formed. This prevents the carrier from adhering to the image forming body. In order to achieve this, it is preferable that the carrier particle size is large because the larger the carrier particle size is, the stronger the magnetic force will be. A uniform thin layer of developer can be formed if the carrier particle size becomes large.In addition, as the carrier particle size increases, the height of the carrier in the thin layer increases and the 7 (4) becomes coarser, resulting in poor developability. When the magnetization is, for example, about 15 to 30 emu/g, the diameter is preferably 1.00 μ or less.
A perspective view and a front view showing the physical structure are shown in Figure 17 (A) and V.
(0). 7a, 7b, 7c 1 in the figure
．． 8a, 81+, and 8c are the stirring blades of the first stirring member, and there are various forms such as square plate blades, disc blades, and elliptical plate blades, and the rotating shafts 9 and 10 respectively. are fixed at angles and/or positions that are 3% apart from each other. 1
1η The two stirring members 7 and 8 are configured in such a way that the stirring areas overlap without the stirring blades colliding with each other; therefore, stirring in the left and right direction (Fig. 16) is performed evenly. Since the stirring plate is tilted f1 (FIG. 17), stirring in the backward direction of IF (FIG. 16) can also be done satisfactorily. Also, r is replenished from the hub 11 via the replenishment roller 12.
This toner is also uniformly mixed into the developer layer in a short time. As described above, the developer layer, which has been sufficiently stirred and has been given the desired frictional charge of 7"L, is transported onto the sleeve 3. During this process, the 1rj layer forming member 5 controls and forms an extremely thin and uniform cutting hole. This developer layer is conveyed in one direction by the rotation of the sleeve 3, and a magnetic bias having a vibration component is generated by the rotation of the magnetic roll 4 in the opposite direction, causing a complicated movement such as rolling on the sleeve 3 at 111f. Therefore, when the toner reaches the developing area 15 and develops the latent image on the image forming member 1 without contact, the toner is effectively supplied toward the latent image surface. As mentioned above, the i+j development process is extremely thin/i'L! (10 .mu.I11-1000 .mu.m), the gap between the image forming body 1 and the sleeve 3, that is, the development gap, can be narrowed to, for example, 500 .mu.l to fully enable non-contact development. When the development gap is narrowed in this way, the electric field in the development area 15 increases, so even if the development bias applied to the sleeve 3 is small, sufficient development can be achieved.
There is an advantage that leakage discharge of developing bias and the like can be reduced. Furthermore, the resolution and other aspects of the image obtained through development are generally improved. The above-described developing method using an extremely thin developer layer has a significant effect, for example, in a developing device with a small-diameter sleeve. That is, conventionally, when non-contact development is performed using a small diameter sleeve of about 30+am or less, a development gap of about 1 mm is required because it is difficult to regulate the layer thickness of the developer jσ. For this reason, a high-voltage AC bias is required, and the resolution, gradation reproducibility, and overall image quality of the image obtained by development deteriorates, especially details such as characters may not be reproduced sufficiently, or the electrical The insulation caused problems such as the design becoming a national disaster. : In contrast, according to the developing method according to the method for forming developer M of the present invention, an extremely thin developer layer I 114 is formed.
Since the developed image is made to be an image, the development gap can be made small, and the electric field is sufficiently large, so that the resolution, gradation reproducibility, and other image quality of the developed image are significantly improved. In addition, since a small-diameter sleeve can be used, the expensive developing device can be made smaller, and it is also easier to arrange the image forming equipment in color electronics, etc., which require multiple developing devices. There is an advantage that the entire apparatus can be made compact.Furthermore, another effect of the developing method using the developer layer forming method of the present invention is that scattering can be suppressed to a minimum even when carriers or toners with small particle diameters are used. In other words, when developing using a conventional developer consisting of small particle size carrier and toner, the carrier and/or toner may scatter and contaminate the inside of the device, or a developing device containing color toner may have an unusual color. There have been problems such as the color balance of the image being disturbed due to the toner being mixed in, and the occurrence of "ragging", etc., but with the development method 1 of the present invention, all of the above-mentioned problems can be solved. Another effect of the invention is that the development method is non-contact development, and only the toner is developed by selectively applying a spoonful of powder toward the latent image surface, which makes it particularly advantageous. This prevents toner fogging and carrier adhesion on the latent image surface, which tend to occur when reversal development is performed using an image forming body. Also, since it does not rub the latent image surface, it may damage the surface of the image forming body.
It does not form brush marks, has good angular image power and gradation reproducibility, and can adhere a sufficient amount of toner to the latent image surface. Furthermore, since the toner image can be superimposed on the image forming body and developed, it is suitable for multicolor development. In addition, as stable development conditions in the development method using the present invention, the developer layer is 10 to 1000 μm, more preferably 400 μII+ or less, and the development gap is 200 μω to 1
It is said to be 200μ bites. Next, the composition of the toner of the developer applied to the developing method using the present invention is as follows. (D thermoplastic resin (binder) 80-90u+L% example:
Borisnarene, styrene acrylic polymer, polyester, polyvinyl butyral, Evokin resin, polyamide resin, polyethylene, ethylene vinyl acetate copolymer, etc., or a mixture of the above■ Pigment (coloring agent) 0-15+LL%
Examples: Black: Carbon blank Yellow: Bennonone derivative Magenta: Rhodamine B lake, Carmine 6B, cyanide diphthalocyanine, sulfonamide derivative dye, etc.■ Charge control agent 0 to 5...L% Plus donor: Nigrosine-based "(uP donating property) Dyes, alkoxylated amines, alkylamides, chelates, pigments, 4a ammonium salts, etc. Negative toners: electron-accepting Bandai complexes, chlorinated paraffins, chlorinated polyesters, polyesters with excess acid groups,
Chlorinated copper phthalocyanine, etc. ■; A cleaning agent: colloidal silica, hydrophobic silica, silicon face, metal soap, nonionic surfactant, etc. ■ Cleaning agent (prevents toner filming on the photoreceptor) Examples: fatty acid metal salts, oxidized silicon acids with organic groups on the surface,
Seven elemental surfactants, etc. ■ Fillers (Improves image surface gloss, reduces raw material costs) Examples: Calcium carbonate, clay, talc, pigments, etc. In addition to these materials, they also prevent fogging on the image surface and toner scattering. To prevent this, a small amount of magnetic powder may be included. As such magnetic powder, particle size is 0.1 to III11.
triiron tetroxide, γ-ferric oxide, chromium dioxide, nickel 7-elite, iron alloy powder, etc. are used.
Contains 1% of 11I. In order to maintain even clearer colors, it is desirable that the amount be 1+uL% or less. In addition, resins suitable for pressure fixing toners that are plastically deformed and fixed to paper by a force of approximately 20 kH/c +a include adhesive resins such as wax, polyolefins, ethylene-vinyl acetate copolymers, polyurethane, and Doom. Resin etc. are used. A toner can be made using the above-mentioned materials by a conventionally known manufacturing method. In this apparatus, in order to obtain a more preferable image, the toner particle size (weight average) is approximately 15 μm or less, 1, 9
It is desirable that it be ~1 μm. If it exceeds 9μm, it will be difficult to obtain sufficient resolution and gradation reproducibility;
If it exceeds the diameter, fine print will become difficult to read, and if it is less than 1 μm, fogging will occur and the image will lose its sharpness. Note that the particle size or average particle size of the toner and carrier in the present invention is 'rf! , it means average particle size, and the weight average particle size is a value measured with a Coulter Counter (manufactured by Coulter Inc.). In addition, the specific resistance of the particles is 0.50cI112
After placing the particles in a container with a cross-sectional area of
It is determined from the current value that flows when an electric field of ~10'V/cτ0 is generated. The structure of the carrier is as follows, and basically the materials listed as the constituent materials of the toner are used. The carrier particles are mainly composed of magnetic particles and resin, and have f! In order to improve image power, resolution, and reproducibility, it is preferably spherical, with a weight average grain size of 100 μm or less, preferably Sμ'n or more and 50μ or less. Chiaria is spherical. As a result, the force received when passing through the gap between the elastic plate and the developer carrier is uniformly applied to the chiaria aggregates, thereby reducing crushing, cutting, etc. of the chiaria, and achieving layering of the chiaria. If the carrier particle size exceeds 50μm1, especially 100μII+, it will inhibit the formation of an i-layer in the developer layer, resulting in poor development and poor image quality.Also, if it is less than 5μm, the developability of the developer and frictional electrification will deteriorate. In addition, the charge is injected by the bias voltage and the carrier adheres to the surface of the photoreceptor, and the carrier that forms the latent image disappears. To prevent this, the resistivity of the carrier is 106Ω.
An insulating carrier with a resistance of cw or more, preferably 10□''Ωcm or more, more preferably 014Ωc1a or more is preferable.Such carriers can be used by coating the surface of the magnetic material with a coating or by coating them with fine magnetic particles. is dispersed in a resin, and the resulting particles are sorted by a known particle size selection means and subjected to f'tI.If the carrier is further spherical, it is carried out as follows: ■Resin-coated carrier: magnetic particles T ■Magnetic powder dispersion carrier: After forming the dispersion resin, spherical treatment is performed using hot air or hot water, or direct spherical dispersion (3 (forming fat) by spray drying. It is preferable to mix the carriers in such a ratio that the total surface area of each carrier is equal. For example, when the average particle size of the toner is 8 μm and the specific gravity is 1.2 g/a
y', carrier average particle size is 20/7 + a specific gravity is 4.5
/C1'', the toner concentration (weight ratio of toner to developer) is 5 to 401IIL%, preferably 8 to 401IIL%.
It is appropriate to reduce the amount by 1 to 25wL%. That is, in the developer of the present invention, unlike a conventional developer in which a large number of small-particle toner particles adhere to the outer periphery of a large-particle carrier, the carrier particle size is small and close to the toner particle size. Therefore, it is preferable that the mixing ratio be such that the total surface area of both is approximately equal. Further, the developer that can be applied to the present invention is not limited to the two-component developer as described above, and in addition to the magnetic carrier and non-magnetic toner, for example, a second non-magnetic toner of a different color may be added to create a three-component developer. The developer may be a component developer, or a three-component developer may be created by adding magnetic toner. Further, in addition to these carrier toners, various additives may be added to form a stable and uniform thin layer. [Example] The present invention will be specifically described below with reference to one example. This is an example in which the present developer and forming method was applied to a multicolor image forming apparatus. FIG. 18(c) shows the structure of the image forming apparatus rC used. The image input unit IN includes an illumination light source 1, a mirror 22, and a lens 7:
23. The -dimensional color CCD image sensor 24 is unitized as a book, and the image input section IN is moved in the direction of arrow X by a drive device (not shown), and the CCD image sensor 24 reads the original. Fix the image manually 1'ttsIN and move the document table 9! The document 25 may be moved by moving the document 25 by J+. The 117 images read by the image input section IN''C are converted into data suitable for recording in the out-of-image FI! section TR. The laser optical system 26 generates an image based on the above image data as follows. A latent image is formed on the image forming member 20, and this latent image is developed to form a toner image on the image forming member 20.The surface of the image forming member 20 is uniformly charged by the scorotron charging electrode 27. Image exposure according to the recorded data is applied from the laser optical system 26 to the image forming body 20 via the lens.
above! ! In this way, a latent image of a streetcar is formed. The object 20 is uniformly charged again by the electrode 27 of the SFlotron I 1 and subjected to image exposure according to recorded data of another color component.The formed latent image of the streetcar is developed by the developing device B containing magenta toner. As a result, a two-color toner image of yellow toner and magenta toner is formed on the image forming body 20. From then on, the cyan toner and the black toner are developed in layers, and the two color toner images are developed on the image forming body 20. A four-color toner image is formed.The developing device A, B, C, and D that accommodates the toner of each color are all similar in structure to the developing device shown in FIG. 16.Developing device A, In B, C, and D, the magnetic roll 4 that conveys the developer with a non-magnetic sleeve 3 containing a built-in magnet roll 4 that rotates in the same direction as the image forming body 1 is S.
It has 9L of poles and N poles alternately each with 4 poles, and the magnetic field at 1u++a on the sleeve is 500-1500G auss.
is desirable, and in this example, 700 Gaus! 3 Magne/
I used a troll. It is preferable that the non-magnetic sleeve 3 has a stainless steel surface with an unevenness of 1 to 10μ+n (11+1), and in this embodiment, the surface of the non-magnetic sleeve 3 is 3μm thick.
A cylindrical sleeve with a diameter of 20 IdItl was used. The rotation speed of the non-magnetic sleeve 3 is 100 to 500 rpI1
11 In this example, the rotation speed of the magnet roll 4 is 240 rpm, which is 2 to 5 times that of the non-magnetic sleeve 3, and is 800 rpm in this example. The elastic plate 5 is fixed to an elastic plate holding member 6, and 17. Regarding the size, it is 0
．． A value between 0.05 and 0.21 am is appropriate, and in this example, it is set to 0.110111. In addition, the elastic modulus of the elastic plate 5 is suitably 5000-25000 kgfz'mm2, and in this example, it is 1.1000 kgf/Io.
It was set as ce 2. Further, the material of the elastic plate 5 is preferably stainless steel, copper, yellow body, steel, etc., but in this embodiment, phosphor bronze was used. The length (free length) from the position where the elastic plate 5 is fixed to the elastic plate holding member 6 to the tip of the elastic plate 5 is 5 to 20 mm.
In this example, it is appropriate that it is between Ia and Ia]
5 m Ia, it contacts the non-magnetic sleeve 3 at Iim from the tip, and its linear pressure is q~l Og/
+n +n is appropriate, and in the example, ls/
ll116. The linear pressure is determined by +ij+ as described above. The non-magnetic sleeve 3 has a power supply 14
From 2, bias voltage (A C2kllz, 1.2kV
p-11, DC-500V) is applied. Stirring plates 7 and 8 are arranged inside the developer storage container, and these members are housed in the casing 2 except for the power supplies 1 and 1. The toner stored in the toner storage unit 11 is fed into the developer container by the toner replenishment control member 12, and the toner is fed into the developer container by the stirring plate 7.
It is mixed with the developer 13 at a temperature of 8°. The developer 13 is supported on the non-magnetic sleeve 3 by the magnetic force of the magnet roll 4, formed into a developer layer of a predetermined thickness (250 μm to 450 μm in this example) by the elastic plate 5, and transported to the development area 15. As a result, the latent image on the image forming body 1 is developed. The multicolor toner image obtained in this way is transferred to the exposure lamp 2.
After the charge is removed by step 8 and transfer is facilitated, the transfer pole 2
9, the image is transferred onto the recording paper P. 29 paper P is separated pole 30
The image forming body 20 is separated from the image forming body 20 and fixed by a fixing device 31. On the other hand, the image forming body 20 is cleaned by the removing electrode 32 and the cleaning device 33. The cleaning device 33 includes cleaning blades 34 and 7.
γ-Bran 35. These are kept out of contact with the image forming body 20 during image formation, and when a multicolor image is formed on the image forming body 20, they come into contact with the image forming body 20 and scrape off residual toner after transfer. Thereafter, the cleaning plate 1!34 separates from the image forming body 20, and a little later, the 7-ar brush 35 separates from the image forming body 20. 7. The upper brush 35 functions to remove toner remaining on the image forming body 20 when the cleaning plate 34 is separated from the image forming body 20. 36 is a roller that collects the toner scraped off by the blade 34. Further, instead of the fur brush 35, a deformable roller such as a trousers roller may be used. The laser optical system 26 is shown in FIG.
7 is a semiconductor laser oscillator, 38 is a rotating polygon mirror, and 39 is an fθ lens. In addition, in such an image forming apparatus, in order to align each image, it is effective to set the timing for starting image exposure by placing optical marks on the photoreceptor and reading them with a sensor, etc. be. In the image forming process in the copying apparatus shown in FIG. 18(c), development is performed by a reversal development method using a developer having the following formulation, and image formation is performed under the image forming conditions shown in Tables 1 to 4. (Developer formulation) Toner composition: Polystyrene 45 parts by weight Polymethyl methacrylate 44 Parifast 0.2 (Charge control agent) Coloring Sharpening 10.5 However, the colorant is Auramine for yellow toner and Rhodamine B for magenta toner. , the cyan toner is copper phthalocyanine, and the black toner is carbon black. Above (■ mix paraboloids,
The desired toner is filtered out by grinding and classifying the toner. Carrier (resin liquid? I carrier) composition: Co7 Niaelite coating (fat: styrene/acrylic (4:6) magnetization 27cm u/y particle size 30μd specific gravity 5.2)/cm' The above composition After mixing, line separation, and classification, a spherical carrier is obtained by hot air treatment. Next, 88 parts by weight of carrier No. 011 and 12 parts by weight of each color toner
The desired developer is obtained by thoroughly mixing the respective parts by weight. Embodiment 1 is the image forming process using the above-mentioned developer, and the developing conditions for forming images of each operating section are as shown in Tables 1 to 4 below. The following margins may be set to Table 1, Table 4, Table 2, i1', and Table 13. The first and second organic photosensitive layers are made of photosensitive waste, with a carrier generation layer containing a trisazo pigment as the lower layer and a carrier transport layer containing an aromatic amino compound as the upper layer, and the developing method is non-contact development. When a multicolor image was formed under the above conditions, an image with good resolution and good reproducibility of the pseudo intermediate 17!4 due to dots was obtained. It was also possible to minimize the scattering of toner and carrier. [Example 2] A carrier prepared as follows was used for a person. Here, "parts" represent parts by weight. Styrene -Acrylic?M m <1■+i composition ratio of styrene, butyl acrylate and methyl methacrylate 57:15:10) 50 parts iron alloy (Fe 9B weight%, 812 weight%, saturation magnetization strength
190e+nu/g) 50 parts of charge-controlled grinding "Nigrosine SO" (Orient Chemical Co., Ltd.) 2 or more parts of the substances are mixed in a ball mill, further kneaded with two rolls, then crushed and classified to form a magnetic carrier with an average particle size of 30μ11. While the coated carrier has a specific gravity of 4 to 5 g/am', the carrier with magnetic material dispersed in the resin as described above has a specific gravity of about 2y/cw', which is the same as that of the toner. approx.], closer to g/cm m'. Therefore,
Because the carrier and toner are more thoroughly agitated,
Furthermore, a uniform developer layer with less scattering is formed. The regulating plate and other conditions were the same as in Example (2). Similar to the first example, good results were obtained in this example. [Embodiment 3] FIG. 19 shows an image forming apparatus n in which a multicolor image is formed during one eave of the image forming body. The difference from the device in FIG. 18(c) is (1) that a charging electrode and an image exposure system (semiconductor laser) are provided between each developing device; (2) the cleaning Vcr 11 is connected to a blade 34 and a toner extracting system; It consists only of the roller 36, and the blade continues to be in pressure contact with the image forming body. (3) Paper conveyance path (4) The thickness of the elastic plate of the developing device was 0.05 mm + free length Oram, and the pressing linear pressure was 2 g/IIm,
Only. For example, when forming a four-color image, image formation is completed approximately four times faster even if the linear velocity is the same as before. The conditions of the pond are the same as in the example. Similar to the f51 example, good results were obtained in this example.Next, regarding the forming force method of the developer layer according to the present invention, i'+
A modification of the if statement explanation will be explained. What is illustrated in FIG. 10 is a modification of the present invention. The requirements of the present invention are that the amount of developer can be controlled by the linear pressure between the elastic plate and the developer carrier and the width of the opening of the wedge-shaped space. Furthermore, by controlling the gap through which the developer passes through by one particle size, it is possible to form a stable and uniform developer layer. The present invention is not limited to elastic plates that are lithographic without the addition of . In this example, the elastic plate 155 is
It is bent so that the surface that is pressed against the developer carrier 153 is convex. This increases the strength of the elastic plate in the longitudinal direction and facilitates handling during manufacturing and assembly. Further, even when the developer carrier 163 has a flat surface, a concave surface, or a convex surface close to a flat surface as shown in FIG. Otherwise, a wedge-shaped space will not be formed at the tip of the elastic plate, and the developer will not be able to slip through the gap between the elastic plate and the developer carrier. FIG. 12 shows another modification of the present invention. Elastic plate 175
By making the shape into such a shape, it is possible to set the formation position of the developer layer (slipping part) very close to the latent image carrier, and after the developer layer is formed, it is possible to set the area where the developer layer is formed until it reaches the development area. Since the distance is shortened, floating toner and foreign matter are less likely to be caught, and scattering of toner and carrier from the developer layer into the air can be minimized. Of course, a cylindrical developer carrier 1 as shown in FIG.
73 as well as an elastic plate 185 as shown in FIG.
If an appropriate curvature is given to the tip of the
Or a developer with a convex surface close to 114 (11 to 1
Book 1831 has been applied since then. In addition, at this time, in order to secure the 1V1-ring of the developer scraped off from the developer carrier, V as shown in FIG. 14 or FIG.
It is desirable that the upper stirring members 177 and 187 be arranged near the -PR plate 175. [Effects of the invention] As is clear from the explanation in J- below, development 1 using the present invention
If you go up to 1 set, the carrier and toner will scatter, and the current
It effectively removes foreign matter in the developer without leakage discharge from the carrier, and enables the development of latent images with high resolution, gradation σ1 development, and image density. 2 and 2 can be made, and the pair) γ is easy to adjust, and l) , j
1j quality is also high. Furthermore, if the developing method using the present invention is applied to a color copying machine, a color printer, etc., it is possible to realize a compact device that does not cause toner color mixing and has excellent color tone reproducibility.

[Brief explanation of drawings]

FIG. 1 shows a stationary side view of one embodiment of the present invention. FIG. 2 shows an enlarged view of the main part of FIG. 1. FIG. 3 is an explanation (■) of FIG. 1. FIG. 4 is a t-graph showing the relationship between gap distance and linear pressure in the example. FIG. 5 is a graph showing the relationship between the play speed of the elastic plate and the amount of developer in the example. FIGS. 6, 7, and 8 show three examples in which the suppressing position of the elastic plate of the developer carrier is different. FIG. 9 shows an example using a belt-shaped developer carrier. 10, 11, 12, and 13 show examples of elastic plates having different shapes. f5] Figures 4 and 15 show the relative positions of elastic plates of different shapes and stirring members (t). Figure 16 is a sectional view of a developing device using the present invention. Figure 17 (a) 17(b) is a front view of the stirring member. FIG. 18(c) is a sectional view of the main parts of the copying device of the embodiment, and FIG. FIG. 19 shows a cross-sectional view of the main part of the image forming device of the embodiment.
6 No. 201, 7I1. is a sectional view showing a layer pressure regulating means for a conventional developer (η). FIGS. 21 and 22 are enlarged views showing the state of the gap formed between the developer carrier and the elastic plate. l, 20...Image forming body:
Llo:l+113i23,13:L]43,15:L
...Developer carrier 4
...magnetic roll 5.105, 115, 125, 135
, 145+], 551165.175... Layer forming member (elastic plate G, IOG... support member 7.8, 117.1.27, 137, 177.187
... Stirring member 11
...
Tosu − Road sweat ゛go° : (Mother 14
...Development bias 110
... Wedge-shaped space Applicant Roku Konishi Photo Industry Co., Ltd. Figure 3 Figure 4 □A Mi ae. Eyebrows44. Figure 6 (rnrn)
Figure 7 Figure 17 (A) Figure 17 (O) 7a 8b Figure 18 (C) Figure 18 (D) 38' Figure 19 35t A Song 481 Giko, Sheath body 3 ta + x Tansaki Kei

Claims (2)

[Claims] (1) A gap having a particle size similar to the magnetic carrier of a developer containing a magnetic carrier and toner is formed between a developer carrier and a layer thickness regulating means, and the developer passes through the gap. A method for forming a developer layer, comprising: forming and holding a developer layer on the developer carrier. (2) Claim 1, characterized in that the layer thickness regulating means is an elastic member that presses against the developer carrier.
A method for forming a developer layer as described in Section 1.