JPS6155658A - Method and device for image formation - Google Patents

Abstract

PURPOSE:To obtain good multicolor images with a small-sized photosensitive body by superposing developed reference toner images to form a multiple reference toner image and removing it after storing it and forming plural picture toner images. CONSTITUTION:A yellow reference signal is inputted to a laser device 12 to form a reference latent image on a photosensitive body 10, and this latent image is subjected to reversal development by a developing device 13 to form a reference toner image, and a magenta toner image formed by a developing device 14 and a cyan toner image formed by a developing device 15 are superposed on said reference toner image to form the multiple reference toner image during one rotation of the photosensitive body 10. This multiple image is removed after its information is stored. Next, a multiple image is formed during three rotations of the photosensitive body by irradiation of a laser device 12 based on stored information and developing devices 13-15. Thus, a transfer drum is unnecessary because plural toner images on the photosensitive body are transferred to a form at a time, and the photosensitive body is made small-sized because the whole of the surface of the photosensitive body is used, and good images are obtained because images are formed on a basis of information of reference toner images.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming method and apparatus for forming a multi-image toner image in which a plurality of image toner images are superimposed on an image support. Electrostatic recording.

Used for facsimiles, transmission records, laser printers, etc.

[Prior art]

In general, in image forming methods and apparatuses that form a plurality of toner images, for example, color image forming methods and apparatuses, the recorded image to be formed has high color density in the image area, less capri in the non-image area, and is faithful to the original. It is required to have good WIIIi properties and good color balance. Therefore, for example, in Japanese Patent Application Laid-open Nos. 49-74034, 1976-127629, and 1977-20730, a reference patch is used to form a reference toner image on an image support, and the reference toner image is Techniques are described for controlling the quality of color images using information from the image. In such known technology, a color image is formed, for example, by the following method. That is, a reference patch is placed on the document table at a position where the document and the document are irradiated with light from a light source in front of the document.
The light reflected from the reference patch and the document is image-exposed onto the photoreceptor, which has been uniformly charged in advance, through a blue filter, for example, to form a reference latent image and an image gR latent image. The reference latent image is then developed by a developing device containing yellow toner to form a yellow reference toner image, followed by formation of a yellow image toner image controlled by information from the reference toner image. This image (toner image) is transferred onto recording paper fed at the same timing from a paper feeding device. On the other hand, the photoreceptor is cleaned of the reference toner image and the residual toner image, and after the residual charge is erased, it is uniformly charged again and exposed through a green filter to form a reference latent image and an image latent image. is formed.

Next, the reference latent image is developed in the same way as the previous time by the developing device containing magenta toner to form a magenta reference toner image, and subsequently information from the reference toner image is controlled to form a magenta image toner image. Ru.

The magenta reference toner image is cleaned and removed, but the magenta toner image is superimposed and transferred onto the recording paper onto which the yellow toner image has already been transferred in the previous step. Similarly, the cyan image toner image is further transferred, and a multi-image toner image in which the three primary color toner images are superimposed is obtained on the recording paper. Next, this recording paper is separated from the transfer drum, and after being fixed, it is discharged outside the machine.

This image forming method has the advantage of being able to provide a color image with improved image characteristics on the - side, but on the other side, (a) a transfer drum is used to transfer the image to the recording paper each time the development of each color is completed. This increases the size of the device and increases the time required for image formation.
(b) Since the development process and the transfer process are repeated many times, there are problems such as misalignment of the toner images of each color, resulting in the formation of an unsightly color image.

Therefore, for example, JP-A-56-144452 and lf! fIm 1983-183152, %JE [1980-
No. 184,381 proposes a technique in which a plurality of color toner images are superimposed on an image support by a reversal development method or the like and are transferred onto recording paper at the same time.

The typical image forming principle of the technique described below will be explained based on the flowchart shown in FIG.

In Figure 5, S is, for example, a drum-shaped photoreceptor, E is the positive surface potential applied to the surface of the photoreceptor S, PH is the image exposed portion of the photoreceptor S, and D is the non-exposed portion of the photoreceptor S. , DUP indicates the increase in potential caused by the adhesion of the charged toner T to the exposed area PH after t=1 development, and cUP indicates the increase in potential of the exposed area I)H caused by the second charging. .

The photoreceptor S is uniformly charged by a Sugorotron band 'rL device or the like, and is given a constant positive surface potential E. This surface potential E decreases to a potential 75 of the exposed portion PH to a point close to zero by the first image exposure.

Here, by performing new reversal development in which development is performed by applying a positive bias in which the DC component is approximately close to the surface potential E of the unexposed area to the developing device, the positively charged toner T in the developing device is developed. A toner image (for example, a yellow toner image) of j.times.1 is formed in such a way that the exposed portion PHK, which has a relatively low potential 17c, adheres to the exposed portion PHK. The region where the toner image was formed increases in value by DUP due to the adhesion of the positively charged toner, but then the second charge is applied by the scorotron charger, resulting in an additional charge. The potential increases by CUP, and a potential close to the surface potential E of the non-exposed area is obtained. Next, a second imagewise exposure is performed on the surface of the photoreceptor S, on which a substantially uniform surface potential B has been obtained, to form an electrostatic charge image. 2 toner images (for example, magenta toner images) are obtained. By repeating the above process, the above-mentioned outer layer is coated on the photoreceptor s.
A multicolor donor image in which toner images (for example, cyan toner images) of the l'ic spear 3 are superimposed is obtained. This multicolor toner image is transferred onto recording paper, fixed by pressure or heat, and then discharged. On the other hand, the photoreceptor S after the transfer and copying is cleaned by a cleaning device and prepared for the next image formation.

According to the above-described image forming principle, the transfer process is performed only once, and there are advantages such as eliminating problems such as increasing the size of the apparatus, prolonging the image forming time, and misalignment of the toner images of each color.

However, in the case of an image toner image formed by overlapping toner images of each color on an image support,
There is a problem in that desired control of image characteristics cannot be achieved using reference toner image information for each color as described in Japanese Patent No. 4034 and the like. That is, even if the image toner images of each color are controlled, the superimposed multiple image toner images are not controlled, resulting in a problem that a high quality color image cannot be obtained. Also, the above-mentioned Japanese Patent Application Laid-open No. 49-7
In an image forming apparatus such as that described in Publication No. 4034, a reference toner image is formed at a previous position on an image support, and an image toner image is formed at a later position based on information from the reference toner image. The area required for the image support increases. For this reason, there are problems in that the entire image forming apparatus becomes large and cannot be made compact.

[Problems to be solved by the present invention]

The problem to be solved by the present invention is that in an image forming apparatus that forms a multi-image toner image by superimposing a plurality of image toner images on an image support, a reference toner image is separately formed and the image toner image is The purpose of this method is to specifically improve the image quality of multicolor images when they are formed under control based on information from a reference toner image. Another object of the present invention is to form an image toner image after the first reference toner image is removed, thereby downsizing the image support and making the entire image device more compact.

[Means to solve the problem]

The above problem arises in an image forming method in which a latent image image formed on an image support is developed to form a multi-image toner image in which a plurality of image toner images are superimposed. a step of forming an image, a forming method for developing the reference latent image to form a multiple reference toner image in which a plurality of reference toner images are superimposed, and a method for developing the latent image image formed on the image support to form a multiple reference toner image In an image forming apparatus having a number of developing devices for forming a multi-image toner image in which image toner images are superimposed, and a cleaning device for removing the toner on the image support, the image latent image is Separately, means for forming a reference latent image is provided, and the reference latent images formed by the means are developed by the plurality of developing devices to form a multiple reference toner image in which the plurality of reference toner images are superimposed. This problem can be solved by an image forming apparatus that is configured in a manner similar to the number of devices distributed.

[For production]

In the image forming apparatus having the above configuration, information on the reference toner image previously formed on the image support is stored in the memory, and the toner image is removed by the cleaning device;
An image toner image is then formed under the control of the information stored in the memory. The image support may be in the form of a drum or an endless belt, and image formation may be performed in one rotation or in multiple rotations corresponding to the number of toner images. In the one-rotation method, when a toner image is formed after the reference toner is removed, the drum diameter can be reduced to a maximum of A in principle if the image support is a drum-shaped photoreceptor, for example.

However, since the number of image forming devices around the drum is large, it is difficult to reduce the diameter of the drum, and it is complicated, so a multi-rotation system is usually preferably employed.

In the multi-rotation method, the drum diameter can be reduced to almost the same as the image length. For example, in the case of a B4 size image, it is possible to reduce the circumference to a drum diameter K of approximately 370 cm. The reference toner image and the image toner image in the present invention are:
A reference latent image and an image latent image are formed by imagewise exposure on an image support member uniformly charged in advance, and then developed sequentially by a plurality of developing devices containing toner of each color. The image exposure is, for example, an output signal of an image sensor that scans a document.

The image signal is a transmission signal from another device or data stored in a storage device, for example, a laser light source.

This is done by modulating or driving the OFT, liquid crystal shutter, LED, etc. with the signal.

The plurality of developing devices perform reversal development based on the image forming principle in flowchart K in FIG. 5, and
A developing device that performs non-contact development is preferably used at least from the second time onwards. In the non-contact developing method, an AC bias is applied to the developing device to cause the contained toner to fly toward the image support for development.
, off alone controls whether the developing operation is turned on or off. Therefore, the development steps of the reference latent image and the image latent image are performed without being influenced by each other. Also, the AC bias is o
In the case of ff, it is preferable that only a DC bias in a direction that prevents the toner from flying is applied. Further, in order to turn off the developing operation, the developing device is separated from the image support, the entire developing device is grounded using a means for removing the developer layer from the sleeve surface, or the developing device is 70-tinged (floated). It's fine in any way.

The image forming mode of the reference toner image and the image toner image in the present invention can take various forms, and typical examples thereof include the 70-chart and the ?
This will be explained with reference to a partial cross-sectional view of the image forming apparatus shown in FIG. Also, is 1 in Figures 1 to 3 5I? A plan view of the drum-shaped photoreceptor in FIG. 5 is shown, and arrows indicate the direction of movement of the photoreceptor surface.

The photoreceptor 1 shown in FIGS. 1 to 3 is first uniformly charged positively and then imagewise exposed by an exposure system modulated or driven based on a reference signal to form a reference latent image. Next, the yellow developing device 5 and the magenta developing device 6 shown in Figure 5 are installed. The cyan developing device 7 and 9 perform reversal development in a non-contact manner to form a multiple reference toner image 2C in which three color reference toner images are superimposed.

Here, information on the reference toner image is stored in a memory and removed by a cleaning device, and then image exposure modulated or driven by an image signal is performed while being controlled by the memory information to form a latent image. It is formed. Next, the image is developed by the developing device 5.6.7 under the control of the memory information, thereby forming a multi-image toner image 3C in which the three-color toner images are superimposed.

Hereinafter, specific image forming modes in each flowchart and their differences will be explained. In the fang 1 diagram, a uniform positive charge is applied to the image support 1, and then image exposure is performed based on a yellow reference signal to form a reference latent image. Thereafter, it is developed by the developing device 5 to form a yellow toner image 2a.

Next, toner development is performed by the developing device 6 without performing charging and image exposure, and a reference toner image 2b is formed in which a magenta toner image is superimposed on the yellow toner image 2a at the same position. Furthermore, cyan toner development is performed by the developing device 7 in the same manner, and the reference toner image 2C at the same position of the three color toner images is removed by f, 1 by the cleaning device, and then almost the entire surface of the image support 1 is used to An image latent image and an image toner image are formed based on information from the reference toner images 2a to 2C. That is,
The image support 1 from which the reference toner image 2C has been removed is uniformly positively charged, subjected to image exposure based on a yellow image signal to form an image latent image, and then developed by the developing device 5. As a result, a yellow toner image 3a is formed. Then uniform charging again.

Image exposure is performed based on the magenta image signal to form an image latent image, and then magenta toner development is performed by the developing device 6, and an image toner image 3b is formed in which the magenta toner image is superimposed on the yellow toner image 3a. It is formed. Furthermore, the same can be done. This toner image 3C is transferred onto the recording wheel by a transfer device and fixed. The image support 1 after the transfer is cleaned and prepared for the next image formation.

The flowchart in Figure 2) differs from the 70-chart in Figure 1 in that the reference toner images of each color are uniformly charged, exposed, and developed, and are formed at different positions. are doing. That is, after a uniform positive charge is applied to the image support 1, image exposure is performed based on a yellow reference signal to form an electrostatic charge image, and then yellow toner development is performed to form a yellow reference toner image 2a. is formed.

After being recharged, image exposure is performed based on the magenta reference signal to form a latent image at a position different from the yellow toner image 2a, and this latent image is further developed with magenta toner to form a magenta toner image. be done. A group 2C is formed in which this magenta toner image and the yellow toner image 2a are superimposed at different positions.

In the flowchart of FIG. 3, the first point is that three colors are written on the image support l at once based on the reference signal, and reference latent images 4 for each color are formed at different positions.
This is different from the flowchart in Figure 2 and Figure 2. Also, in the flowchart of the Ki44Nio 2 diagram above, multiple! ! The difference is that the i-quasi-toner image is formed by three revolutions of the image support, but in this case it is formed by one revolution. That is, after the image support 1 is uniformly positively charged, it becomes yellow.

Three color reference signals of magenta, cyan, and cyan are written simultaneously to form reference latent images 4 at mutually different positions. This reference latent image is sequentially developed by a developing device 5.6.7, and a superimposed multiple reference toner image 2C is formed by one revolution of the image support.

Overlapping the toner images in the above solid image forming method means that the toner images of each color are formed in a common area, and when all the toner adhesion parts overlap at the same position, 1
, they may partially overlap or may not overlap entirely.

〔Example〕

The present invention will be specifically explained below with reference to Examples, but the embodiments of the present invention are limited to K (Example 1). Figures 6 to 10 are diagrams for explaining this example. Figure 6 is a cross-sectional view of the main parts of a three-color image forming apparatus, Figure 7 is a cross-sectional view of an exposure device using a laser source, Figure 118 is a cross-sectional view of a developing device, and Figure 119 is a cross-sectional view of a reference toner image. FIG. 10 is a flowchart illustrating the development mode. FIG. 10 is a 70-chart illustrating the toner image development mode.

In this embodiment, the image forming apparatus shown in FIG. 6 forms an image based on the 70-chart in FIG.
00vK uniform charging is applied. Next, the yellow reference signal is inputted to the laser device [12] having the structure shown in FIG.
A reference latent image is formed by irradiating the charged surface (first image exposure).

Thereafter, as shown in the development mode in Fig. 9, the development device [1
3, reversal development (first development) is performed to form a reference toner gK (FIG. 1, 2a) to which yellow toner T is attached. Next, υ reversal development (two-time development) is performed by the developing device 14 without charging or image exposure, and magenta toner T' adheres to the yellow toner P, resulting in a reference toner image (FIG. 1, 2b). is formed. Similarly, the multi-reference toner image (FIG. 1, 2c), which is subjected to reversal development (35 times of development) by the developing device 15 and the cyan toner image is superimposed at the same position, is created as an image. Q1
Formed by rotation.

This multiple reference toner image is stored in memory before being cleaned and is then irradiated with laser light from a laser device 12 modulated to a yellow image signal (once the image is imaged). An image latent image is formed by the exposure), and is developed by the developing device 13 (first development) to form a yellow image toner 18! (FIG. 1 3a) is formed. Next, an image latent image is formed on the image support 10 by irradiation with laser light modulated with a magenta image signal (112 image exposures) after being recharged, and is further developed by the developing device 15 (2 times development). ) and the magenta image toner image is superimposed on the yellow image toner image (see FIG.
b) formed. Recharge in the same way.

Image exposure based on cyan image signal (j.3 image exposure).

The 70-chart in FIG. 10 shows the development mode of the image toner image. That is, the toner deposited by double or triple development is deposited on both the area to which toner has adhered in the previous process and the area to which toner has not adhered.

This image toner image is given transferability by the action of the pre-transfer charger 16 and the pre-transfer exposure device 170, and then placed on a recording paper P of, for example, 84 plates, which is supplied in synchronization with the image support 10, using a transfer electrode 180. It is transcribed by action.

Thereafter, this recording paper P is transported by transport rollers 19, fixed and discharged. On the other hand, after the image support 10 has been transferred, the charge is removed by the charge removal device 13, and the remaining toner is cleaned by the second blade of the cleaning device 21, which was released during image formation.

Figure +7 is a sectional view showing the configuration of the laser device 12,
23 is a laser light source, 24 is a modulator that performs a modulation operation based on an external signal, 25 is a polygonal reflecting mirror, 26 is an fθ-lens for imaging, and 27 and 28 are reflecting mirrors.

8 is a sectional view illustrating the structure of the post-development fi 13, 14, and 15, in which 29 is a developing sleeve made of a non-magnetic material such as aluminum or stainless steel, and 30 is provided inside the developing sleeve 29. 31 is a layer thickness regulating blade made of a magnetic or non-magnetic material that regulates the thickness of the developer layer formed on the developing sleeve 31; 32 is a layer thickness regulating blade formed from above the developing sleeve 29; a scraper blade for removing the developer layer after development; 34 a stirring rotor for stirring the developer in the developer reservoir 33; 36 a toner hopper; 35 having a recess on the surface into which toner enters;
A toner supply roller 37 supplies toner from the toner hopper 36 to the developer reservoir 33, and a toner supply roller 37 applies a bias voltage including an oscillating voltage component to the developing sleeve 29 via a protective resistor 38. The figure shows that the developing sleeve 29 and the magnet body 3o each rotate in the direction of the arrow. is fixed, the magnet body 30 is fixed, or the developing sleeve 29 and the magnet body 3 are fixed.
o may rotate in the same direction. In order to make the magnetic flux density of the magnetic pole facing the image support 10 larger than the magnetic flux density of other magnetic poles, a lifting platform having a fixed magnet body 3o usually has strong magnetization or a magnetic pole with the same polarity or Two magnetic poles of different polarities are placed close to each other.

In such a developing device, the magnetic pole of the magnet body 3o is usually 500~
It is magnetized to a magnetic flux density of 1500 gauss, and its magnetic force attracts the developer in the developer reservoir 33 to the surface of the developing sleeve 29, and the absorbed developer is transferred to the layer thickness regulating blade 3.
The thickness of the developer layer is regulated by 1, and the developer layer moves in the same direction or in the opposite direction (in the figure, the same direction) to the direction of the rotation arrow of the image support 1°, and the developer layer is moved to the developing sleeve 2.
mgR of the image support 10 is developed in the development area E where the surface of the image support 10 faces the surface of the image support 10, and the residue is removed from the surface of the development sleeve 29 by the scraper blade 32 and returned to the developer reservoir υ33. This is what happens.

The development is repeated at least twice in order to superimpose the color toner & e--The toner adhered to the image support 10 in the previous development will not be shifted in the subsequent development. In this embodiment, the reference latent image is preferably based on the non-contact developing conditions as shown in the developing device 13.
The reference toner image is developed by using the vibration bias in the power supply 37 such as 14.15 as the reference vibration bias. This reference toner image is detected, for example, by a mathematical means that measures the reflection density using a combination of a light emitting element and a light receiving element. This detected information is
1c is compared with the stored memory, and an appropriate bias value is selected as the applied voltage when developing the image latent image.

Also, (1) select an appropriate value from among the reference vibration bias values that vary according to a certain program and use it as the bias value when developing the image latent image; Furthermore, in comparison with the memory stored in the CPU, (3) the band KlE position and/or the image exposure amount to the image support 10 can be controlled.
4 is a D/A converter, 40 is an A/I converter, and 41 is a photo sensor for measuring reflection density.

Next, in this embodiment, the voltage rA37 is normally on with an AC bias of 1.2 Kv at 2 KHz, and +
A DC bias of 5 oov is applied, but this value is controlled to fluctuate based on information from the reference toner image.Also, the sleeve 41 has a diameter of 30 m and a diameter of 65 r in the direction of the arrow.

P and m, and the gap d between the developing area E and the image support 10 was 11000 μm. The gap between the sleeve 29 and the thick film regulation grade 31 is 300 μm1 The formed developer layer is about 700 μm1 N, S with a magnetic flux density of 900 Gauss
The number of rotations in the direction of the arrow of the magnet body 30 having six magnetic poles at equal intervals was 7 oor, p, m.

make an impact.

Incidentally, the resistivity is the value obtained by applying a load of IK9/lx'' to a particle having a cross-sectional area of 0.5.0 cm'', which also serves as a load body.

Further, the carrier preferably has an average particle size of less than 5 μm,
If necessary, the fluidized toner such as hydrophobic silica preferably has an average particle size of 1 to 20 μm, which is made by adding various pigments and a charge control agent as necessary to a resin, and has an average charge amount of 3. ~300 μc/g, especially preferably 5 to 30 μC/g. If the average particle size of the toner is less than 1 μm, it will be difficult to remove the gloss, and if it exceeds 20 μm, the image resolution and resolution will decrease. When using a developer consisting of a mixture of an insulating carrier and toner such as 0 ゛ or more, it is applied to the developing sleeve 31 in FIG. It becomes possible to easily set the electrostatic image so that it adheres sufficiently to the electrostatic image and does not cause fogging, without fear of causing leakage. In addition, in order to effectively control the development movement of the toner by applying such a magnetic force, the toner should be coated with a magnetic material such as 9 to the extent that the clarity of the color is not impaired. The body may also be included.

Of course, the present invention is not limited to two-component developers, such as those described in US Pat. No. 3,893,418.

A non-contact development method using a one-component developer described in JP-A-55-18656 to JP-A-55-18659 can also be used.
3゜Japanese Patent Application Publication No. 59-42565 1. Special request 1982
-97973゜Special Application 1987-231434 ☆ Saimei 1-
The method described in ti can also be used.

In this example, 50% by weight of magnetite was dispersed in the resin, the average particle size was 20 μm, and the magnetization was 30 emu.
/9, and a carrier having a resistivity of 10 Ωα or more is used.

The toner is a styrene-acrylic resin and a benzidine derivative as a yellow pigment.

Rhodamine B is used as a magenta pigment, 10 parts by weight of a copper phthalocyanine pigment is used as a cyan pigment, and 2 parts by weight of a positive charge control agent are used, each having an average particle diameter of 10 μm. In this example, the content ratio of toner to developer is 20 J.
A developer adjusted to have an amount of i% is used.

In this embodiment, a method is adopted in which a reference toner image and an image toner image are formed using a reference signal and an image signal from the outside, and an image toner image is formed after the reference toner image is removed. Since this method is adopted, the formation position and formation method of the reference toner image can be selected from a wide range. Further, the reference toner image may be activated from an image signal, or may be formed using a signal from a master wedge provided with a certain color density difference. Also, the order in which the cyan, magenta, and yellow color toner images are formed may be changed arbitrarily depending on the situation (Example 2) The difference between this example and Example 1 is that
This is the point where the reference toner images of each cyan color appear at the same position. Therefore, each time a reference toner image is formed, charging, exposure, and development must be repeated nine times, and the steps are shown in the flowchart of FIG. 11. That is, the toner adhesion position in the first WJ development is different from the toner adhesion position in the second development. On the other hand, the image forming mode of the reference toner image in this embodiment is close to the image forming mode of the image toner image, and has the advantage that effective information can be easily obtained.

〔Effect of the invention〕

As is clear from the above examples, in the present invention, a plurality of toner images are superimposed on an image support and transferred onto recording paper at once, so a transfer drum is not required. In addition, since the image toner image can be formed using almost the entire surface of the image support, the image support can be downsized, and the image forming apparatus can be made partially compact. Furthermore, since image formation is performed based on information from the reference toner image, a multicolor image with good image quality, one gradation, and color contrast <2 can be obtained. Furthermore, when a plurality of toner images f and i are formed on the image support, a reversal development method and a non-contact development method are used, so the image is clear and the fatigue of the photoreceptor is reduced. A number of effects are achieved, such as the ability to easily and rationally control the developing operation when developing each latent image without waste.

[Brief explanation of drawings]

1, 2, and 3 are flowcharts for explaining a preferred image forming mode of the present invention, FIG. 4 is a partial sectional view of an image forming apparatus for explaining the flowchart, and FIG. 5 is a known known method. 70 to explain the image creation mode using the reversal development method of
- Showing a chart; FIG. 6 is a cross-sectional view of the main parts of an image forming apparatus for explaining an embodiment;
FIG. 7 is a sectional view of the laser device, FIG. 8 is a sectional view of the developing device, FIG. 9 is a 70-chart explaining the development mode of the reference toner image of Example 1, and FIG. 10 is the image toner of the example. FIG. 11, a flowchart illustrating the image development mode, shows the reference toner image development mode of the second embodiment. 10...Drum-shaped photoreceptor, 11...Scorotron charger, 12...Laser device, 13
,14.15...Developer, 16...
...Pre-transfer exposure device, 17...Pre-transfer charger, 1
8... Transfer electrode, 29... Sleeve,
30...Magnet, 31...Layer thickness regulating blade, E...Development area, 37...Development bias, 39...D /A converter, 40...
...A/D converter, 41...Photo sensor, T, T'...Toner, D...Developer, P...Recording Paper, Y, M, C...Yellow, Magenta, Cyan. Agent Patent Attorney No 1) Father-in-law Figure 1 Figure 2 Figure 3 C Figure 4 Figure 7//,,p,' Figure 8/Nowo ((4,75) Figure 9

Claims (9)

[Claims] (1) In an image forming method in which a latent image image formed on an image support is developed to form a multi-image toner image in which a plurality of image toner images are superimposed, a reference latent image is formed separately from the latent image image. and developing the reference latent image to form a multiple reference toner image in which a plurality of reference toner images are superimposed, and after the plurality of reference toner images are removed, the plurality of reference toner images are removed. An image forming method characterized by forming an image toner image. (2) The image forming method according to claim 1, wherein the image toner image is controlled by information from the reference toner image. (3) The image forming method according to claim 1 or 2, wherein the plurality of image toner images are formed by multiple rotations of the image support. (4) The image forming method according to any one of claims 1 to 3, wherein the plurality of reference toner images are formed by superimposing them on a common reference latent image. (5) Claim 1, wherein the plurality of reference toner images are independently formed on reference latent images at different positions.
The image forming method according to items 3 to 3. (6) The image forming method according to claim 1, wherein the image latent image is formed on substantially the entire image forming surface of the image support. (7) a plurality of developing devices for developing the image latent image formed on the image support and superimposing a plurality of image toner images to form a multi-image toner image; In an image forming apparatus having a cleaning device for removing, a means for forming a reference latent image separately from the image latent image is provided, and the reference latent image formed by the means is developed by the plurality of developing devices to form a plurality of reference latent images. An image forming apparatus comprising: forming a multiple reference toner image in which toner images are superimposed, and forming the plurality of image toner images after the plurality of reference toner images are removed by the cleaning device. . (8) The image forming apparatus according to claim 7, wherein at least one of the plurality of developing devices used for second and subsequent development is a non-contact developing device. (9) The image forming apparatus according to claim 7 or 8, wherein the plurality of developing devices are reversal developing devices.