JP3117153B2 - Recording method for electrophotographic apparatus - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording method and an electrophotographic apparatus in which a toner image formed on a recording medium is transferred to a recording sheet and then the recording sheet is peeled off the recording sheet. The present invention relates to an improvement in a technique for separating a recording sheet from a photoconductor in an electrophotographic apparatus.

[0002]

2. Description of the Related Art In general, as represented by an electrophotographic apparatus, a toner is formed on a recording medium by applying a toner according to image information by a developing machine, and the toner image is formed on the recording paper from the recording medium. Some are designed to be transcribed. In such a recording method, after the recording paper is picked from the paper cassette, the toner image on the photoreceptor is electrostatically transferred in the transfer unit, and then separated from the recording body and transported to the fixing unit. It is thermally fixed in the fixing section.
The recording paper separates when the rigidity of the recording paper exceeds the electrostatic attraction between the recording medium and the recording paper as the main force, so it is generally installed in the device after the transfer of the toner image. A method of neutralizing the electric charge of the recording paper by generating an alternating current corona discharge by the static eliminator provided is used.
In this case, a separation claw that mechanically separates the recording sheet adsorbed on the recording medium may be provided in order to surely separate the recording sheet. Further, unnecessary toner adhesion called fog on the background portion of the toner image may be intentionally caused on the recording surface.

[0003]

By the way, generally, in order to separate the recording paper from the recording medium, when the radius of curvature of the recording medium is small so that the rigidity of the recording paper easily acts, that is, when the diameter of the recording medium drum is small. This is effective when the recording medium is small or when the recording medium has a belt shape and the radius of curvature of the transfer portion is small.

However, when printing at a high speed as in a recent electrophotographic apparatus or the like, a charger, a developing machine, a cleaner, and the like provided around the recording drum are large, so that the diameter of the recording drum is large. However, there is a problem that the recording paper cannot be easily separated from the recording drum. Further, in the apparatus in which the recording paper is forcibly peeled off from the recording medium by the separation claw, the separation claw comes into contact with the recording medium, so that there is a problem that the life of the recording medium is shortened by repeating the contact. On the other hand, in the case where an unnecessary toner called fog is attached to the surface of the recording medium, there is a problem that the toner attachment cannot be stably controlled. Further, if the static elimination by the static eliminator is strengthened, the toner image transferred to the recording paper scatters, and as a result, a problem occurs that the image is disturbed.

In view of the above circumstances, an object of the present invention is to make it possible to easily and reliably peel off a recording sheet from a recording medium without adding mechanical means, and to shorten the life of the recording medium. Another object of the present invention is to provide a recording method of a recording medium and a recording method of an electrophotographic apparatus which can prevent the image from being disturbed, and another object of the invention is to provide an electrophotographic apparatus which can appropriately execute the above method. Is to do.

[0006]

An electrophotographic apparatus according to the present invention is provided.
In the method of recording the position , the photoreceptor is recorded by the exposure means.
Irradiates light based on the image information to be recorded to the surface of the photoconductor
An electrostatic latent image is formed on the surface, and the electrostatic latent image is
Toner image on the surface of the photoreceptor
Is formed, and the toner image is transferred to a recording sheet to form the recording image.
In a recording method of an electrophotographic apparatus for recording an image on paper
When the light is irradiated by the exposure means,
The image to be recorded at a position corresponding to the leading edge of the recording paper
Different from the information and the amount of light from the light based on the image information
Irradiates a small amount of dot-shaped controlled light
Was .

[0007]

[Action] As above mentioned, the irradiation to a position corresponding to the leading end of the recording sheet on the surface of the photosensitive body, unlike the image information to be recorded, and the light of the information weaken the suction force of the recording sheet with respect to the photosensitive member and, since the recording paper is to weaken the force sucking from the photoreceptor, even larger radius of curvature of the photosensitive member, it is possible to easily separate the recording sheet from the photoreceptor. Moreover, the mechanical means of what such as the release of the recording paper
It does not require, Ru prevents the by mechanical contact life of the photoreceptor shortens. Furthermore, since it need not increase the charge removing effect, the printed image is rather disturbed Turkey Togana an effect of increasing the reliability.

[0008]

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows an embodiment of an electrophotographic apparatus for carrying out the method of the present invention, and FIG. 2 is an explanatory diagram showing the relationship between the amount of laser light and the amount of adhered toner. In FIG. 1, a drum-shaped photoconductor 1 constituting a recording medium is rotatably mounted, and the photoconductor 1 rotates clockwise. Photoconductor 1
In the process of the rotation, the photosensitive member 1 is uniformly charged, for example, by passing through the charger 2, and then the exposure unit 3A irradiates the laser beam 3 to form an electrostatic latent image on the photosensitive member 1. You. The exposure means 3A modulates image information to be recorded, and irradiates the modulated light as a laser beam 3. Further, when the rotation of the photoconductor 1 further proceeds, the electrostatic latent image on the photoconductor 1 is reversely developed by the positively charged toner in the developing device 4 to form a toner image 5. The developing device 4 contains two components including a toner and a carrier, and the toner is positively charged by friction with the carrier. When the formed toner image 5 reaches the transfer unit 8, the transfer unit 8 generates a negative corona discharge, thereby causing the recording paper 7 on the paper conveyance path 6 to move.
Is electrostatically transferred to A static eliminator 9 is installed near the transfer device 8. When the recording paper 7 is negatively charged by the transfer of the toner image 5, the static eliminator 9 is applied to the photosensitive member 1 where the recording paper 7 is positively charged. This is for preventing strong absorption and winding around the photoreceptor 1, and removes negative charges of the recording paper 7 by AC corona discharge. Therefore, the recording paper 7 on which the toner image 5 is transferred
Is neutralized by passing through the static eliminator 9, and then
By passing through the fixing device 10, the toner is thermally fixed.
On the other hand, when the photoreceptor 1 is transferred, the residual charge remaining on the surface of the photoreceptor 1 is erased by the eraser 11, and the residual toner is removed by the cleaner 12.
Will be reused.

In the embodiment, the spacer toner 51 is adhered by the developing device 4 to the position a corresponding to the leading end A of the recording paper 7 on the surface of the photosensitive member 1. More specifically, the spacer toner 51 acts as a spacer between the photoreceptor 1 and the recording paper 7, and
This is for facilitating the peeling of the recording paper 7 by weakening the electrostatic attraction force between them, and is almost inconspicuous, almost inconspicuous, and substantially similar to unnecessary toner called fog adhering to the background portion of the toner image 5. At the time of development by the machine 4, it is formed only at a position a corresponding to the leading end A of the recording paper 7 on the surface of the photoconductor. As a range to which the spacer toner 51 adheres, it is important to prevent the spacer toner 51 from overlapping the image to be recorded when it is recorded on the recording paper 7 and to obtain releasability. A range within about 20 mm from the tip is preferable, and actually
Within. Therefore, when irradiating the photoconductor 1, the exposing unit 3A irradiates the position a of the photoconductor 1 with a laser beam different from the laser beam 3 for generating the toner image 5 to the position a of the photoconductor 1 by the exposing unit 3B. I have to. That is, the exposing section 3B emits one dot of the laser beam for generating the spacer toner 51 to the toner image 5.
Is not the same as the irradiation of the laser beam 3 for generating the toner image 5, but the laser beam for generating the spacer toner 51 is made weaker than the irradiation of the laser beam 3 for generating the toner image 5.

The relationship between the amount of laser beam and the state of toner adhesion will be described with reference to FIG. In FIG. 1A, (1) shows a normal 1 for forming the toner image 5.
(2) shows the beam shape when the laser power is reduced to half by power modulation, and (3) shows the beam shape when the irradiation time is shortened by half and the spot diameter is reduced by pulse width modulation. Are shown, respectively. In FIG. 2B, (1) to (3) show the toner adhesion states corresponding to (1) to (3) shown in FIG. 2A, respectively. 2 (a) and 2 (b), the toner adhesion state is smaller than that of (1) in the case of toner image generation (2) in the case where the laser power is reduced by half, and the case where the spot diameter is smaller. (3) is about 1/5
It can be seen that the area becomes about １ ／ and becomes narrow. Therefore, when the exposure means 3A irradiates the position a of the photoreceptor 1, the exposing section 3B reduces the amount of the laser beam or reduces the laser spot diameter to reduce the adhesion area of the spacer toner 51 during development. As a result, a black dot of one dot is not recognized. In addition, at this time, if the spacer toner 51 is attached with some periodicity or regularity, it becomes more conspicuous, and therefore, it is preferable that the spacer toner 51 be attached irregularly so as to be sparse. Further, the exposing section for peeling 3B
When the laser beam is irradiated, at the position a of the photoconductor 1, the light amount of the laser beam is gradually reduced from the leading end to the inside of the recording paper 7 so that the spacer toner 51 attached to the recording paper 7 is made less noticeable. At the same time, the image information recorded on the recording paper 7 is not affected.

[0011] Next, described an embodiment of the present invention a method in connection with the operation of the embodiment.

When the photoreceptor 1 rotates, the photoreceptor 1 is positively charged by a charger 2, and the surface of the photoreceptor 1 is irradiated with a laser beam 3 which modulates image information to be recorded by exposure means 3A. To develop. In this case, the exposing means 3A has an exposing portion 3B for peeling, and the exposing portion 3B emits a laser beam different from the laser beam 3 modulating the image information to the leading end A of the recording sheet 7 on the surface of the photoreceptor 1. Is irradiated to the position a corresponding to. At that time, position a
When compared with a laser beam that modulates image information, the amount of light or the spot diameter is smaller than that of a laser beam that modulates image information. Thereafter, when the developing device 4 develops the photoconductor 1 with the rotation of the photoconductor 1, a toner image 5 is formed on the photoconductor 1 in accordance with image information, and a spacer toner 51 is placed at a position a of the photoconductor 1. Adhere to. Photoconductor 1
Is advanced, and the toner image 5 and the spacer toner 51 on the photoreceptor 1 are electrostatically transferred by the transfer device 8 to the recording paper 7 in the paper transport path 6. At this time, since the recording paper 7 is negatively charged, the photosensitive member 1 that is positively charged is charged.
Try to be strongly sucked.

However, as described above, since the spacer toner 51 is attached to the position a of the photoconductor 1, the spacer toner 51 acts as a spacer between the photoconductor 1 and the recording paper 7, and 1 can be reliably reduced. Therefore, even when the recording paper 7 is transferred to the recording paper 7 by the photoconductor 1, the recording paper 7 can be easily peeled off from the photoconductor 1. This means that during development of the photoconductor 1, unnecessary toner adhesion called fog occurs on the background of the toner image 5 on the photoconductor 1, but the more fog the image, the more the recording paper on the photoconductor 1 This is also evident from the phenomenon of little winding.

Accordingly, since the electrostatic attraction to the photoreceptor 1 is weakened by the spacer toner 51, the transferred recording paper 7 can be easily and reliably peeled off from the photoreceptor 1 when the static eliminator 9 removes the electricity. Moreover, at that time, it is not necessary to enhance the static elimination effect of the static eliminator 9. After the charge is removed, the recording paper 7 is thermally fixed by the fixing unit wetness 10 and is discharged outside the apparatus.

In the method of the present invention, as described above, the laser beam for generating the spacer toner 51 is irradiated to the position a corresponding to the leading end A of the recording sheet 7 on the surface of the photoreceptor 1, When developed, the spacer toner 51 is attached to the position a of the photoconductor 1, and the force with which the recording paper 7 is attracted to the photoconductor 1 at the time of transfer by the spacer toner 51 can be weakened. Even if it is large, it is possible to enable the recording paper 7 to be easily separated from the photoconductor 1. In addition, since it is not necessary to provide any mechanical means as in the related art, it is possible to prevent the life of the photoconductor 1 from being shortened, and it is not necessary to enhance the static elimination effect of the static eliminator 9, so that the recorded image may be disturbed. Absent. When the laser beam 3 is irradiated on the photoconductor 1, the laser beam for generating the spacer toner 51 has a smaller light amount or a smaller spot diameter than the laser beam 3 for generating the toner image 5. Since the irradiation is performed, the spacer toner 5 at the position “a” of the photoconductor 1 is irradiated.
1 can be reduced, and when recorded on the recording paper 7, the trace of the spacer toner 51 can be prevented from being recognized by human eyes as a black dot of one dot, and is not noticeable. Furthermore, when sparsely radiated, the spacer toner 51 adheres randomly, so that it is less noticeable. In addition, if the position a of the photoconductor 1 is radiated so as to gradually decrease from the leading end to the inside of the recording sheet 7, the amount of the spacer toner 51 attached changes accordingly. 51 is made less noticeable, and the image information recorded on the recording paper 7 is not disturbed.

In the embodiment of the electrophotographic apparatus, the electrophotographic apparatus includes a photosensitive member 1, an exposing unit 3A, a developing unit 4, and a recording sheet 7, and the exposing unit 3A includes an exposing unit 3B for peeling.
Since the laser beam is applied to the position a of the photoreceptor 1 by the exposing unit 3B, the above method can be performed accurately. In the illustrated embodiment, the transfer of the toner image 5 from the photoreceptor 1 to the recording paper 7 and the peeling of the recording paper 7 by the static eliminator 9 are performed by direct corona discharge to the recording paper 7. When used in a belt transfer system in which transfer is performed on a recording paper 7 via a derivative belt, the belt transfer system has a large application effect because it is difficult to quickly remove electricity and the recording paper has poor peelability. Further, in the illustrated embodiment, an example is shown in which the exposing means is constituted by a laser scanning system in which the photosensitive member 1 is irradiated with the laser beam 3, but other than that,
For example, a so-called ionography technology that ejects ions modulated in accordance with image information to be recorded on a dielectric by toner recording, an electrostatic recording technology, and a magnetography technology that develops a magnetic latent image with a magnetic toner. As a matter of course, the present invention can be applied to all recording techniques using toner.

[0017]

As described above, according to the first aspect of the present invention, in the recording method of the electrophotographic apparatus, the exposure method is used.
When the light by the stage irradiation, at a position corresponding to the tip portion of the recording sheet in a photosensitive member, unlike with the image information to be recorded,
A dot having a smaller amount of light than light based on the image information
Irradiates the light in a controlled manner, and the recording paper is sucked from the photoconductor
The recording paper can be easily separated from the photoreceptor even if the radius of curvature of the photoreceptor is large, and no mechanical means is required.
Since no Ru can <br/> is possible to prevent the life of the photoreceptor is reduced. Further, since it need not increase the charge removing effect, Ri no longer leaflet print image disturbance Turkey, an effect that may correspondingly increase reliability. According to the second aspect of the present invention,
In a recording method of an electrophotographic apparatus, the light
During irradiation, the position corresponding to the leading edge of the recording paper on the photoconductor
The image information to be recorded, and
Dot control with smaller spot diameter than light based on information
Controlled light is emitted, so the dots on the photoreceptor
Possible to reduce the adhesion area of the spacer toner at the irradiation position shaped for light, because traces of the human eye or lath Pesatona can be prevented from being recognized as one dot of black spot,
High-quality recording can be performed without obscureness . Ma
According to the third aspect of the present invention,
Is the image according to any one of claims 2 to 6,
Since the light different from the information was sparsely illuminated,
By the spacer toner randomly adhered to the recording paper
Record quality can be improved without any noticeable
You . According to the invention described in claim 4, according to claim 1,
The invention according to claim 3, wherein the image
The light different from the image information is
It gradually decreases from the tip to the inside
The spacer toner adhering to the recording paper.
The image recorded on the recording paper can be made less noticeable.
Improve recording quality without interfering with image information
Can be Further, according to the invention described in claim 5, according to the invention described in any one of claims 1 to 4 ,
The irradiation range of light different from the image information is used for recording.
Since it is approximately 20 mm from the leading edge of the paper,
The spacer toner to be applied can be made more inconspicuous
And does not interfere with the image information recorded on the recording paper.
Recording quality can be further improved, and
It is informative .

[Brief description of the drawings]

FIG. 1 is an overall view showing an embodiment of an electrophotographic apparatus for carrying out a method of the present invention.

FIG. 2A is an explanatory diagram when the light amount of a laser beam is changed, and FIG. 2A is an explanatory diagram showing a toner adhesion state corresponding to a change in the laser light amount.

[Description of Signs] 1 ... Photoconductor, a ... Position corresponding to the leading end of recording paper on the surface of photoconductor, 2 ... Charger, 3 ... Laser beam, 3A ...
Exposure means, 3B: peeling exposure section, 4: developing machine, 5: toner image, 51: spacer toner, 7: recording paper, A: leading end of recording paper.

──────────────────────────────────────────────────の Continued on the front page (72) Inventor Masato Miwa 1060 Takeda, Katsuta-shi, Ibaraki Prefecture Inside Hitachi Koki Co., Ltd. (72) Inventor Koji 1060 Takeda, Katsuta-shi, Ibaraki Prefecture Inside Hitachi Koki Co. 56) References JP-A-62-161173 (JP, A) JP-A-2-29761 (JP, A) JP-A-2-23375 (JP, A) JP-A-61-165782 (JP, A) 62-206569 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/04-15/04 120 G03G 15/047 G03G 15/14-15/16 G03G 21/00 370-500 G03G 21/14

Claims (5)

(57) [Claims] To 1. A photosensitive member is irradiated with light based on image information to be recorded by exposure means to form an electrostatic latent image on the surface of the photosensitive member, a developing machine thus reversal develops the electrostatic latent image do it
Forming a toner image as image information on the surface of the photoconductor ,
The toner image is transferred to a recording sheet and the image is transferred to the recording sheet.
The recording method of an electrophotographic apparatus for recording, upon irradiation of light by the exposing unit, the position corresponding to the leading end of the recording sheet in a photosensitive body, unlike the image information to be recorded, and based on the image information Less light than the light
Electrons characterized by irradiating controlled light in a slit shape
Recording method for photographic equipment . To 2. A photosensitive member is irradiated with light based on image information to be recorded by exposure means to form an electrostatic latent image on the surface of the photosensitive member, a developing machine thus reversal develops the electrostatic latent image do it
Forming a toner image as image information on the surface of the photoconductor ,
The toner image is transferred to a recording sheet and the image is transferred to the recording sheet.
The recording method of an electrophotographic apparatus for recording, upon irradiation of light by the exposing unit, the position corresponding to the leading end of the recording sheet in a photosensitive body, unlike the image information to be recorded, and based on the image information Smaller spot diameter than light
Recording method for an electrophotographic apparatus, wherein the benzalkonium be irradiated with again dotted controlled light. 3. A light different from the image information is sparsely illuminated.
3. The method according to claim 1 or 2, wherein
A recording method for an electrophotographic apparatus according to any of the above . 4. The light different from the image information is transmitted to a surface of a photoreceptor.
From the leading edge of the recording paper to the inside
Claims 1 to 5 characterized in that they are gradually reduced.
A recording method for an electrophotographic apparatus according to claim 3 . 5. An irradiation range of light different from the image information ,
It is about 20 mm from the leading edge of the recording paper
The electron according to any one of claims 1 to 4,
Recording method for photographic equipment .