JPH0994999A - Toner image forming unit and color image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce in size a body of a color image forming apparatus by eliminating exposure means for forming an electrostatic latent image. SOLUTION: The color image forming apparatus comprises toner image forming units 15 for forming the toner images 17 of respective prime colors, transfer means 18 for sequentially transferring the images 17 formed by the units 15 to a print sheet 10, and fixing means 12 for fixing a color toner image 19 combined by the final unit 15. The toner image forming unit comprises a toner conveyor 16, toner layer forming means for forming a toner layer on the conveyor 16, and toner releasing means for forming the image 17 by releasing the unnecessary part of the toner layer based on an image signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner type color image forming apparatus and a toner image forming unit used therein.

[0002]

2. Description of the Related Art In recent years, a toner type color image forming apparatus typified by a laser printer has become widespread, and this toner type color image forming apparatus can form a color image having a clear density, so that high quality printing is possible. Suitable for
Hereinafter, such a toner type color image forming apparatus will be described.

18 and 19 are schematic configuration diagrams of a conventional color image forming apparatus. In FIG. 18, the photoconductor 1 is formed by a seamless belt, and the surface thereof is coated with a layer of an organic photoconductive material. By rotating the photoconductor 1 in the direction of the arrow, an image for one color among the four primary colors yellow, magenta, cyan, and black is sequentially formed. Hereinafter, a series of flow of the color image forming process will be described.

The charging means 2 causes the surface of the photoreceptor 1 that has passed-
The exposing means 3 which is uniformly charged to about 600 V and which is composed of an optical system such as a laser irradiator and a polygon mirror irradiates a laser beam on the basis of the image signal sent, and the surface potential of the exposed portion is -100 V. The electrostatic latent image is formed on the surface of the photoconductor 1 by pulling it up to a certain degree. The developing means 4 is composed of four parts for each primary color. The developing means 4Y is yellow, the developing means 4M is magenta, and the developing means 4C is cyan.
The developing means 4B develops one of the four primary colors by the toner 4a incorporated therein, such as black.

For example, when developing yellow,
In order to make the electrostatic latent image a visible image, the developing unit 4Y attaches the developing roller 4b to which the negatively charged toner 4a is attached to the photoreceptor 1.
And the toner 4a is transferred to the electrostatic latent image portion on the surface of the photoconductor 1 to form a yellow toner image 4c. The intermediate transfer roller 5 applies a positive voltage from the back side of the intermediate transfer body 6 in order to transfer the toner image 4c formed on the surface of the photosensitive body 1 to the intermediate transfer body 6, and also the intermediate transfer body 6 is transferred to the photosensitive body 1. Toner image 4
c is attracted from the surface of the photoconductor 1 to be peeled off and transferred to the intermediate transfer body 6.

The cleaning means 7 is provided for the photosensitive member 1 after transfer.
The surface of the photoconductor 1 is physically cleaned by removing the toner remaining on the surface of the photoconductor 1 with a cleaning blade or a cleaning brush, and the neutralization unit 8 removes the negative toner remaining on the surface of the photoconductor 1 after removing the residual toner. Photoreceptor 1 by neutralizing the charge
The surface of the is electrically cleaned.

By repeating this series of steps in the order of magenta, cyan and black, a color toner image 4d in which the four primary colors are combined is formed on the intermediate transfer member 6.

As shown in FIG. 19, the transfer means 9 applies a positive voltage from the back side of the printing paper 10 in order to transfer the color toner image 4d formed on the surface of the intermediate transfer body 6 to the printing paper 10. The negatively charged color toner image 4d is attracted from the surface of the intermediate transfer member 6 and separated to be transferred to the printing paper 10.

The cleaning means 11 is freely detachable from the intermediate transfer body 6, and when contacted with the intermediate transfer body 6, the toner remaining on the surface of the intermediate transfer body 6 after the transfer is removed by a cleaning blade or a cleaning brush to perform the intermediate transfer. The surface of the body 6 is physically cleaned. When the removal of the toner is completed, the cleaning unit 11 returns to the fixed position shown in FIG. 18 which is separated from the intermediate transfer body 6 again.

The fixing means 12 sandwiches the printing paper 10 on which the color toner image 4d has been transferred between the pressure roller 13 and the heating roller 14 having a heat source therein, and melts the toner particles to form a color image on the printing paper 10. Fix it.

[0011]

However, in the conventional color image forming apparatus as described above, in order to form an image with the toner 4a, the electrostatic latent image which is the basis of the image is first formed of yellow, magenta and cyan. , Must be formed for each black. For this reason, it is necessary to separately provide four developing means, and moreover, the charging means 2 for charging the surface of the photoconductor 1, the exposing means 3 for forming an electrostatic latent image, and the discharging means 8 for electrically cleaning. Was indispensable in the construction of the color image forming apparatus. Among these, the exposure means 3 composed of an optical system such as a laser irradiator and a polygon mirror is inevitably bulky in size, and the existence of the exposure means 3 impedes the difficulty of downsizing the main body. Had a point.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and provide a toner image forming unit and a color image forming apparatus in which the exposure unit for forming an electrostatic latent image is eliminated and the main body is miniaturized. To do.

[0013]

In order to solve the above problems, the present invention is provided with each toner image forming unit for forming a toner image for each primary color, and each toner image forming unit is provided with a toner carrier. And a toner layer forming means for forming a toner layer on the toner carrier, and a toner peeling means for peeling off an unnecessary portion of the toner layer based on an image signal to form a toner image. A transfer means for sequentially transferring the toner images formed in step 1 to a print sheet and a fixing means for fixing the color toner image combined in the final toner image forming unit to the print sheet are provided.

[0014]

With this configuration, in each toner image forming unit, the air ejected from the nozzle of the print head of the toner peeling unit blows off and peels off an unnecessary portion of the toner layer, and a toner image is formed on the remaining portion. Can be done.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. In this embodiment, the toner image forming unit itself forms the central portion of the color image forming apparatus. Parts having the same functions as those of the conventional example shown in FIG. 18 are designated by the same reference numerals.

(Embodiment 1) FIGS. 1 and 2 are schematic configuration diagrams of a color image forming apparatus according to a first embodiment of the present invention, and FIG. 3 is a color image forming apparatus according to the first embodiment of the present invention. And FIG. 4 is a perspective view of the print head of the toner image forming unit of the color image forming apparatus according to the first embodiment of the present invention.
First, a series of steps of the color image forming process will be briefly described, then, the principle of toner image forming will be described, and finally, the configuration of the toner peeling unit will be described in detail.

First, a series of steps of the color image forming process will be briefly described. In FIG. 1, the toner image forming unit 15 is composed of four parts for each primary color. The toner image forming unit 15Y is yellow, the toner image forming unit 15M is magenta, the toner image forming unit 15C is cyan, and the toner image forming unit. Four parts correspond to the four primary colors, for example, 15B is black. In this embodiment, each toner carrier 16 of the toner image forming unit 15 is formed of a non-photosensitive drum, and the toner carrier 16 rotates in the direction of the arrow so that one of the four primary colors is formed. Images are sequentially formed.

For example, when forming a yellow image of the four primary colors, the toner carrier 16 of the toner image forming unit 15Y rotates in the direction of the arrow to sequentially form a yellow toner image 17. Then, the transfer means 18 formed of a corotron, a transfer roller, or the like applies a positive voltage from the back side of the print paper 10 in order to transfer the toner image 17 formed on the surface of the toner transport body 16 to the print paper 10. Then, the negatively charged toner image 17 is attracted from the surface of the toner conveying body 16 to be peeled off and transferred to the printing paper 10 to form a yellow image.

This series of steps is repeated in the order of magenta, cyan and black, and as shown in FIG. 2, the black toner image 17 formed by the final toner image forming unit 15B is superposed. Then, on the printing paper 10,
A color toner image 19 formed by combining images of four primary colors of yellow, magenta, cyan, and black is formed as a color image.

The fixing means 12 sandwiches the printing paper 10 on which the color toner image 19 has been transferred between the pressure roller 13 and the heating roller 14 having a heat source therein, and melts the toner particles to form a color image on the printing paper 10. Fix it.

Next, the four primary color toner image forming unit 15
The principle of toner image formation inside will be described in detail. The four toner image forming units 15 have the same structure except that the colors of the toners stored in the four toner image forming units 15 are the same, and therefore the yellow toner image forming unit 15Y will be described as an example with reference to FIG. Proceed.

In FIG. 3, the toner container 20a of the toner layer forming means 20 contains a yellow toner 20b, and the toner 20b is negatively charged by being attached to the replenishing roller 20c. The toner layer forming means 20 presses the negatively charged toner 20b onto the surface of the toner carrier 16 by the rotation of the replenishing roller 20c and transfers the toner 20b to form a yellow solid toner layer 20d. The thin layer forming blade 20e thins and uniformizes the thickness of the toner layer 20d to about 30 μm. In this way, the toner carrier 16
A yellow toner layer 20f in a solid coating state is formed thereon.

The toner peeling means 21 is composed of a print head 22 and a toner dust collector 23. As shown in FIG. 4, the print head 22 has a plurality of nozzles 22a corresponding to the resolution.
Are arranged in an array corresponding to the print width. The print head 22 selectively ejects air from a plurality of nozzles 22a based on the image signal sent, and blows off and removes unnecessary portions of the toner layer 20f in a solid coating state.
In this way, the portion left on the surface of the toner carrier 16 becomes the toner image 17.

At this time, if a negative voltage having the same polarity as the charging polarity of the toner layer 20f is applied by the applying means 24 from the back side of the surface of the toner conveying body 16 which faces the toner peeling means 21, the toner layer 20f becomes more dense. It becomes easier to peel off.
A toner dust collector 23 is installed on the upstream side of the print head 22, and a voltage having a polarity opposite to the charging polarity of the toner, that is, a positive voltage is applied to the charging portion 23a of the toner dust collector 23. It is charged. The toner that is blown off and scattered in the toner layer 20f is attracted to and collected by the charging unit 23a to which a positive voltage is applied, and is transported to the toner container 20a of the toner layer forming unit 20 by a transport unit (not shown) for reuse. .

The transfer means 18 applies a positive voltage from the back side of the printing paper 10 in order to transfer the toner image 17 formed on the surface of the toner conveying body 16 to the printing paper 10, and the toner image 17 is charged negatively. Is attracted from the surface of the toner carrier 16 to be peeled off and transferred to the printing paper 10. In this way, a yellow image is formed on the printing paper 10. Also,
By a similar process, magenta, cyan and black images are formed.

The cleaning means 25 is the toner carrier 1.
The toner remaining on the surface of 6 is removed by a cleaning blade or a cleaning brush to clean the surface of the toner carrier 16. However, the toner carrier 16
The toner layer forming means 20 forms a toner layer on the surface of the toner layer 20d.
Will be formed into a solid coating state again, and also
Since the rotation of the replenishing roller 20c itself produces a cleaning effect, the installation of the cleaning means 25 is not an essential requirement.

In the toner image forming unit 15 described above, the main body is integrated into a cartridge to save the trouble of maintenance and inspection.

Finally, the structure of the toner removing means will be described in detail. 5 and 6 are schematic cross-sectional views showing an example of the nozzle structure of the print head 22 of the toner image forming unit in the first embodiment.

As described above, the toner image forming unit 15
The toner removing means 21 is composed of a print head 22 and a toner dust collector 23. As shown in FIGS. 4 to 6, the print head 22 is provided with a plurality of nozzles 22a corresponding to the resolution, and the nozzle 22a. The air ejected from is controlled by opening and closing a door formed by two piezoelectric elements 22b provided on the inner surface of each nozzle 22a. When a voltage is applied, the piezoelectric element 22b is distorted and deformed into a semi-cylindrical shape as shown in FIG. 6, and the raised portions contact the doors from both sides so as to close the door to block the passage of the nozzle 22a and block the ejection of air. When the application of the voltage is stopped, the distortion of the piezoelectric element 22b is restored as shown in FIG. 5, and the raised portion sinks to open the door to open the passage of the nozzle 22a and eject the air.

The jetting of air can be controlled by other methods, and FIG. 7 is a schematic sectional view showing another example of the nozzle structure. For example, as shown in FIG. 7, the heating element 22c is provided on one side of the inner surface of the nozzle 22a, and the surface of the heating element 22c is covered with the resin 22d so as to enclose the gas 22e.
When the heating element 22c in such a state is energized, the gas 22e covered with the resin 22d thermally expands due to the heat generated by the heating element 22c, the resin 22d rises, and the raised portion closes the door, as shown in FIG. Then, the passage of the nozzle 22a is closed to block the ejection of air. When the energization is stopped, the resin 22d also contracts with the contraction of the gas 22e, and as shown in FIG. 7, the raised portion sinks to open the door, opens the passage of the nozzle 22a, and ejects air.

The print head 22 constructed as described above
Is a plurality of nozzles 22a based on the image signal sent.
Air is selectively ejected from the toner layer 20 as a solid image from the surface of the toner carrier 16 as shown in FIG.
The unnecessary portion indicated by the hatching of f is blown off and separated, and the toner image 17 is formed on the portion remaining on the surface of the toner carrier 16 as shown in FIG.

The block surrounded by the broken line of the toner layer 20f in FIG. 9 represents each dot corresponding to the nozzle 22a, and since the thickness of the toner layer 20f itself is about 30 μm, it is ejected from the nozzle 22a. Even with air, the toner for the corresponding dots can be sufficiently blown off. At this time, if the air that has been charged positively or negatively in advance by using a charging device (not shown) is ejected from the nozzle 22a, the separation of the toner layer 20f can be further promoted. Furthermore, by applying a negative voltage having the same polarity as the charging polarity of the toner layer 20f in the vicinity of the nozzle 22a, it is possible to prevent toner from adhering to the nozzle 22a.

The toner blown off and scattered in the hatched portion of the toner layer 20f is attracted and collected by the positively charged charging portion 23a of the toner dust collector 23 described above, and the toner is conveyed by a conveying means (not shown). It is transported to the toner container 20a of the layer forming means 20 and reused.

The nozzle 22 is shown in FIG. 4 used in the above description.
Although the print head 22 in which a is arranged in an array is shown, the structure of the print head 22 is not limited to one fixed in an array, but one that moves left and right to form an image like a print head of an ordinary printer. May be

(Embodiment 2) Toner peeling means 2 of this embodiment
6 removes an unnecessary portion of the toner layer 20f by sucking the toner 20b together with air from the nozzle 27a to form a toner image 17. Since the present embodiment and (Embodiment 1) are different only in the configuration of the toner peeling means 26, only the toner peeling means 26 having the different points will be described, and duplicate description will be omitted.

FIG. 11 is a schematic configuration diagram of the periphery of the toner peeling means of the color image forming apparatus according to the second embodiment of the present invention,
12 is a perspective view of a print head of a color image forming apparatus according to the second embodiment of the present invention, and FIGS. 13 to 16 are nozzle structures of the print head of the color image forming apparatus of the second embodiment of the present invention. It is a schematic sectional drawing which shows.

As shown in FIG. 11, the toner peeling means 26 is composed of a print head 27 and a toner dust collector 28. As shown in FIGS. 12 to 14, the print head 27 has a plurality of print heads depending on the resolution. The nozzles 27a are provided in an array corresponding to the print width, and the air sucked from the nozzles 27a is
Suction is controlled by opening and closing a door formed by two piezoelectric elements 27b provided on the inner surface of each nozzle 27a. When voltage is applied, as shown in FIG. 14, the piezoelectric element 2
7b is distorted and deformed into a semicylindrical shape, and the raised portions come into contact from both sides so as to close the door to block the passage of the nozzle 27a and block the suction of air. When the application of the voltage is stopped, the distortion of the piezoelectric element 27b is restored as shown in FIG. 13, and the raised portion sinks to open the door to open the passage of the nozzle 27a and suck the air.

The suction of air can be controlled by other methods. For example, as shown in FIG. 15, a heating element 27c is provided on one side of the inner surface of the nozzle 27a, and the surface of the heating element 27c is covered with a gas 27e by a resin 27d. Cover it as if to enclose it. When the heating element 27c in such a state is energized, the resin 27 is heated by the heating element 27c as shown in FIG.
The gas 27e covered with d thermally expands and the resin 27d rises, and the raised portion closes the passage of the nozzle 27a so as to close the door to block the suction of air. When electricity is stopped, gas 27
The resin 27d also contracts as e shrinks, and as shown in FIG. 15, the raised portion sinks to open the door and opens the passage of the nozzle 27a to suck air.

The print head 27 selectively sucks air from the plurality of nozzles 27a on the basis of the image signal sent thereto, and air is applied to unnecessary portions of the solid toner layer 20f shown by hatching in FIG. At the same time, it is sucked and peeled off, and a toner image 17 is formed on the portion remaining on the surface of the toner carrier 16 as shown in FIG.

The block surrounded by the broken line of the toner layer 20f in FIG. 9 represents each dot corresponding to the nozzle 27a, the thickness of the toner layer 20f itself is about 30 μm, and the toner particles are about 10 μm. So nozzle 2
Even the air sucked from 7a can sufficiently suck the toner for the corresponding dots. At this time, if the air that has been positively or negatively charged in advance by using a charging device (not shown) is ejected from the nozzle 27a, the separation of the toner layer 20f can be further promoted. Further, by applying a negative voltage having the same polarity as the charging polarity of the toner layer 20f in the vicinity of the nozzle 27a, it is possible to prevent the toner from adhering to the nozzle 27a.

The toner sucked in the hatched portion of the toner layer 20f is carried to the air flow and is attracted to the positively charged charging portion 28a of the toner dust collector 28 to be collected, and the carrying means (not shown). The toner is then conveyed to the toner container 20a of the toner layer forming means 20 and reused.

The nozzle 2 shown in FIG.
7a shows the print heads 27 arranged in an array, but the structure of the print heads 27 is not limited to the one fixed in an array, and the print heads 27 can be moved left and right to form an image like the print heads 27 of a normal printer. It may be one.

As described above, the present invention provides the toner carrier 1.
The unnecessary portion of the toner layer 20f formed in 6 is blown off or sucked to be peeled off, and the toner image 17 is formed on the remaining portion of the toner layer 20f. In the embodiment, the description has been made on the assumption that the toner carrier 16 is a drum type, but the toner carrier 16 itself may be a belt type.

(Third Embodiment) In the above embodiment, each toner carrier 16 of the toner image forming unit 15 is a non-photoconductor, but the toner carrier 16 is charged like a photoconductor. By being made of a material, the toner carrier 1
It is also possible to electrically attach the toner onto the sheet 6. FIG. 17 shows an embodiment in which the toner carrier 16 is made of a charging material. In this case, the charging means 2 is provided in front of the toner layer forming means 20, and the surface of the toner carrier 16 which the charging means 2 has passed is uniformly charged to about −100V. Further, the charge removing unit 8 is provided after the cleaning unit 25, and the negative charge remaining on the surface of the toner carrier 16 after the charge removing unit 8 removes the residual toner is neutralized to electrically charge the surface of the toner carrier 16. To clean.

[0045]

According to the present invention, each toner image forming unit for forming a toner image for each primary color, transfer means for sequentially transferring the toner image formed by each toner image forming unit to a print sheet, and the final toner. The toner image forming unit includes a fixing unit configured to fix the color toner image combined by the image forming unit onto a print sheet, the toner image forming unit, a toner layer forming unit forming a toner layer on the toner carrying unit, and an image signal. By removing the unnecessary portion of the toner layer on the basis of the toner peeling means for forming a toner image, the air ejected from the nozzle of the print head of the toner peeling means blows off the unnecessary portion of the toner layer and peels it off. However, the toner image can be formed on the remaining portion, and the exposure unit for forming the electrostatic latent image is not required, and the color image forming apparatus can be significantly downsized. That.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a color image forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a color image forming apparatus according to a first embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a toner image forming unit of the color image forming apparatus according to the first embodiment of the present invention.

FIG. 4 is a perspective view of the print head of the toner image forming unit of the color image forming apparatus according to the first embodiment of the present invention.

FIG. 5 is a schematic cross-sectional view showing the structure of the nozzles of the print head of the toner image forming unit of the color image forming apparatus in the first embodiment of the invention.

FIG. 6 is a schematic cross-sectional view showing the structure of the nozzles of the print head of the toner image forming unit of the color image forming apparatus in the first embodiment of the invention.

FIG. 7 is a schematic cross-sectional view showing the structure of the nozzles of the print head of the toner image forming unit of the color image forming apparatus in the first embodiment of the invention.

FIG. 8 is a schematic cross-sectional view showing the structure of the nozzles of the print head of the toner image forming unit of the color image forming apparatus in the first embodiment of the invention.

FIG. 9 is a diagram showing a printing state of the color image forming apparatus according to the first embodiment of the present invention.

FIG. 10 is a diagram showing a printing state of the color image forming apparatus according to the first embodiment of the present invention.

FIG. 11 is a schematic configuration diagram around a toner peeling unit of a color image forming apparatus according to a second embodiment of the present invention.

FIG. 12 is a perspective view of a print head of a color image forming apparatus according to a second embodiment of the present invention.

FIG. 13 is a schematic sectional view showing a structure of a nozzle of a print head of a color image forming apparatus according to a second embodiment of the present invention.

FIG. 14 is a schematic cross-sectional view showing a structure of a nozzle of a print head of a color image forming apparatus according to a second embodiment of the present invention.

FIG. 15 is a schematic sectional view showing a structure of a nozzle of a print head of a color image forming apparatus according to a second embodiment of the present invention.

FIG. 16 is a schematic sectional view showing a structure of a nozzle of a print head of a color image forming apparatus according to a second embodiment of the present invention.

FIG. 17 is a schematic configuration diagram of a toner image forming unit of a color image forming apparatus according to a third embodiment of the present invention.

FIG. 18 is a schematic configuration diagram of a conventional color image forming apparatus.

FIG. 19 is a schematic configuration diagram of a conventional color image forming apparatus.

[Explanation of symbols]

 10 printing paper 11 cleaning means 12 fixing means 13 pressure roller 14 heating roller 15 toner image forming unit 15Y toner image forming unit 15M toner image forming unit 15C toner image forming unit 15B toner image forming unit 16 toner carrier 17 toner image 18 transfer Means 19 Color toner image 20 Toner layer forming means 20a Toner container 20b Toner 20c Replenishing roller 20d Toner layer 20e Thin layer forming blade 20f Toner layer 21 Toner peeling means 22 Print head 22a Nozzle 22b Piezoelectric element 22c Heating element 22d Resin 22e Gas 23 Toner dust collector 23a Charging part 24 Applying means 25 Cleaning means 26 Toner peeling means 27 Print head 27a Nozzle 27b Piezoelectric element 27c Heating element 27d Resin 27e Body 28 Toner precipitator 28a charging unit

Claims (16)

[Claims] 1. A toner carrier, a toner layer forming means for forming a toner layer on the surface of the toner carrier, and a toner peeling means for peeling off an unnecessary portion of the toner layer based on an image signal to form a toner image. And a toner image forming unit. 2. The toner peeling means comprises a print head for ejecting air from a plurality of nozzles, and the air ejected from the nozzles of the print head peels off unnecessary portions of the toner layer,
The toner image forming unit according to claim 1, wherein a toner image is formed on the remaining portion. 3. The toner image forming unit according to claim 2, wherein the charged air is ejected. 4. The toner peeling means comprises a print head for sucking air from a plurality of nozzles, and sucks air from the nozzles of the print head to peel off unnecessary portions of the toner layer,
The toner image forming unit according to claim 1, wherein a toner image is formed on the remaining portion. 5. At least a pair of piezoelectric elements are provided in the passage on the inner surface of the nozzle, a voltage is applied to the piezoelectric elements based on an image signal, and the passage is opened / closed by the ups and downs of the piezoelectric elements. The toner image forming unit according to claim 2, wherein the toner image forming unit is a toner image forming unit. 6. At least one heating element containing a gas and covered with a resin film is provided in the passage on the inner surface of the nozzle, and the heating element is energized based on an image signal to prevent the resin film from rising or sinking. The toner image forming unit according to claim 2 or 4, wherein the passage is opened and closed by an operation. 7. The toner image forming unit according to claim 2, wherein a voltage having the same polarity as the charging polarity of the toner is applied near the nozzle. 8. The toner image according to claim 2, wherein a toner dust collector is provided on the upstream side of the print head, and a voltage having a polarity opposite to that of the toner is applied to a charging portion of the toner dust collector. Forming unit. 9. A voltage of the same polarity as the charging polarity of the toner layer is applied to the toner layer from the back side of the surface of the toner carrier facing the toner peeling means. The toner image forming unit described. 10. The toner image forming unit according to claim 1, wherein the toner carrier is a drum. 11. The toner image forming unit according to claim 1, wherein the toner carrier is a seamless belt. 12. The toner image forming unit according to claim 2, further comprising a cleaning unit for removing the residual toner from the toner carrier. 13. The toner image forming unit according to claim 2, wherein the unit main body is integrally formed to form a cartridge. 14. A toner carrier is made of a chargeable material, a charging means is provided in front of the toner layer forming means, and the surface of the toner carrier which is passed by the charging means is uniformly charged and after the cleaning means. A charge removing means is provided, and the charge removing means is configured to electrically clean the surface of the toner carrier by neutralizing the negative charges remaining on the surface of the toner carrier after removing the residual toner. The toner image forming unit according to claim 1, wherein the toner image forming unit is a toner image forming unit. 15. A toner carrier, a toner layer forming means for forming a toner layer on the surface of the toner carrier, and a toner peeling means for peeling off an unnecessary portion of the toner layer based on an image signal to form a toner image. A plurality of toner image forming units each including a toner image forming unit, each toner image forming unit containing a toner of a different color, and a transfer unit for sequentially transferring the toner images formed by the respective toner image forming units to a print sheet; And a fixing unit for fixing the color toner image synthesized by the toner image forming unit to the printing paper. 16. A color image forming apparatus according to claim 15, wherein the toner image forming unit is integrally formed to form a cartridge.