JP2003287913A - Belt photoreceptor and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt photoreceptor which is simple in structure, low in production cost, and high in durability and contributes to the miniaturization of the device, and to provide an image forming apparatus. <P>SOLUTION: In a color laser printer 1, a photoreceptor mechanism 31 has the belt photoreceptor 33 on which a visible image is formed by supplying toner with a developing roller 35 after an electrostatic latent image is formed. The belt photoreceptor 33 is constituted of a base material layer 67 made of a conductive resin and a photosensitive layer 69 made of an organic photoreceptor, which are arranged in a laminate. Power is supplied from a first belt photoreceptor roller 39 and a third belt photoreceptor roller 43 which support the belt photoreceptor 33. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt photosensitive member and an image forming apparatus used in a color laser printer or the like.

[0002]

2. Description of the Related Art Conventionally, toner is carried on an electrostatic latent image formed on a belt photosensitive member to form a visible image, and then,
A color laser printer has been used in which the visible image is transferred onto an intermediate transfer belt, and further, the visible image is transferred onto a recording medium and thermally fixed.

As shown in FIG. 4, a belt photosensitive member P1 used in such a color laser printer has a base material layer P3.
It has a structure in which a vapor deposition layer P5 and a photosensitive layer P7 are sequentially laminated on top, and is wound around a belt photosensitive roller P9. The photosensitive layer P7 is formed by leaving a part of the vapor deposition layer P5, and the vapor deposition layer P5 is exposed on the surface in that portion. The vapor-deposited layer P5 exposed on the surface is coated with a conductive paint layer P6 mainly composed of carbon,
The brush feeder P11 is in contact therewith. still,
FIG. 4 is a cross-sectional view of the belt photoconductor P1 in the width direction.

In this belt photoreceptor P1, the photosensitive layer P
Reference numeral 7 is a portion where an electrostatic latent image is formed by uniformly charging the entire surface by a charging device (not shown) and then exposing it according to a predetermined pattern. Further, the vapor deposition layer P5 of the belt photosensitive member P1 is, when the photosensitive layer P7 is charged and exposed as described above, a brush power supply unit that charges the back side of the photosensitive layer P7 with a charge corresponding to the surface side thereof. It is a layer to be supplied from P11.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
1 has a complicated structure because it is necessary to provide the base material layer P3, the vapor deposition layer P5, the photosensitive layer P7, and the conductive coating layer P6.
There is a problem that the manufacturing cost becomes high.

Further, since the mechanical strength of the vapor deposition layer P5 is weak, the photosensitive layer P7 is easily separated from the base material layer P3, and the durability of the belt photosensitive member P1 is insufficient.
Furthermore, since a dedicated brush power feeder P11 is required to feed power to the belt photosensitive member P1, the color laser printer has a complicated configuration, which increases the manufacturing cost and reduces the size of the apparatus. There was a problem that it would be difficult.

The present invention has been made in view of the above points, and has a simple structure and can keep the manufacturing cost low.
An object of the present invention is to provide a belt photosensitive member and an image forming apparatus which have high durability and can be downsized.

[0008]

Means for Solving the Problems and Effects of the Invention (1) The invention of claim 1 is a belt photosensitive member for forming an electrostatic latent image, comprising a conductive base material layer and a photosensitive layer. A belt photosensitive member is characterized in that the volume resistivity of the conductive base material layer is in the range of 10 ³ to 10 ⁹ Ω · cm.

The belt photoreceptor of the present invention has a volume resistivity of 1
Since a conductive base material layer having a resistance of 0 ⁹ Ω · cm or less is provided, power is supplied from, for example, a member in contact with the belt photosensitive member from the conductive base material layer side (for example, a roller supporting the belt photosensitive member). be able to. Therefore, if the belt photosensitive member of the present invention is used in an image forming apparatus such as a color laser printer, a member supporting the belt photosensitive member can be used as a power feeding unit, and an independent power feeding unit need not be provided. Therefore, the structure of the image forming apparatus can be simplified and the manufacturing cost thereof can be reduced.

Further, in the belt photoreceptor of the present invention, since the volume resistivity of the conductive base material layer is 10 ³ Ω · cm or more,
It is possible to reduce the amount of the component (for example, carbon) blended for imparting conductivity to the conductive base material layer. Therefore, the belt photosensitive member does not become brittle and has sufficient durability. (2) The invention according to claim 2 provides the belt photoreceptor according to claim 1, wherein the surface resistivity of the conductive base material layer is 2 × 10 ⁴ Ω / □ or more. .

In the belt photoreceptor of the present invention, the surface resistivity of the conductive base material layer is 2 × 10 ⁴ Ω / □ or more, so that a portion of the conductive base material layer is the same as the conductive base material layer. Even if it has a potential different from that of other portions, a large current does not flow between the portions having different potentials. (3) The invention of claim 3 provides a belt photosensitive member, characterized in that the photosensitive layer is formed on the conductive base material layer.

In the belt photosensitive member of the present invention, since the photosensitive layer is formed on the conductive base material layer, the structure is simple and the manufacturing cost of the belt photosensitive member can be reduced. Further, in the belt photoreceptor of the present invention, since the vapor deposition layer is not interposed between the conductive base material layer and the photosensitive layer, the adhesive strength between the conductive base material layer and the photosensitive layer is high. Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (4) In the invention of claim 4, in the conductive base material layer,
The ten-point average roughness Rz indicating the surface roughness on the side where the photosensitive layer is formed is in the range of 0.01 to 10 μm. The body is the gist.

In the belt photoreceptor of the present invention, in the electroconductive substrate layer, the roughness on the side where the photoconductive layer is formed is within the above range, so that the adhesive force between the electroconductive substrate layer and the photosensitive layer is high. . Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (5) In the invention of claim 5, in the conductive base material layer,
The surface on which the photosensitive layer is formed is roughened by a chemical etching process.
The belt photoreceptor according to any one of items 1 to 4 is a gist.

In the belt photoreceptor of the present invention, in the conductive base material layer, the side on which the photosensitive layer is formed is roughened by chemical etching, so that the adhesive strength between the conductive base material layer and the photosensitive layer is high. Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (6) In the invention of claim 6, in the conductive base material layer,
The surface of the side on which the photosensitive layer is formed is roughened by blasting, and the belt photosensitive member according to any one of claims 1 to 4 is summarized.

In the belt photoreceptor of the present invention, in the conductive base material layer, the side on which the photosensitive layer is formed is roughened by the blast treatment, so that the adhesive strength between the conductive base material layer and the photosensitive layer is high. Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (7) The invention of claim 7 is characterized in that the photosensitive layer contains a polycarbonate resin and the conductive base material layer is made of a polyethylene resin or a polycarbonate resin. The belt photoreceptor described in (1) is used as the gist.

The present invention exemplifies a photosensitive layer and a conductive substrate layer. This belt photoreceptor can positively charge the photosensitive layer. (8) In the invention of claim 8, the photosensitive layer is formed by laminating an undercoat layer made of polyamide, a charge generation layer, and a charge transport layer, and the conductive base material layer is made of polyamide resin. The belt photosensitive member according to any one of claims 1 to 6 is characterized in that.

The present invention exemplifies a photosensitive layer and a conductive substrate layer. This belt photoreceptor can negatively charge the photosensitive layer. (9) The invention of claim 9 is an image forming apparatus including a belt photosensitive member for forming an electrostatic latent image, wherein the belt photosensitive member directly or indirectly forms a conductive base material layer and a photosensitive layer. The gist of an image forming apparatus is characterized in that the image forming apparatus is provided with a power supply unit that is formed by stacking layers and supplies power to the conductive base material layer from a side where the photosensitive layer is not formed.

In the image forming apparatus of the present invention, since electric power is supplied to the conductive base material layer of the belt photosensitive member from the side where the photosensitive layer is not formed, a conductive portion for supplying electric power is provided on the photosensitive layer side. No need. Therefore, the structure of the belt photosensitive member can be simplified, and the manufacturing cost of the image forming apparatus can be reduced. (10) The invention according to claim 10 is characterized in that the image forming apparatus according to claim 9 is characterized in that a supporting member for supporting the belt photosensitive member is provided, and the supporting member is the power feeding means. .

In the image forming apparatus of the present invention, since the supporting member for supporting the belt photosensitive member is the power feeding means, it is not necessary to separately provide the power feeding means. Therefore, the structure of the image forming apparatus can be simplified and the manufacturing cost thereof can be further reduced. (11) The invention according to claim 11 is summarized as the image forming apparatus according to claim 10, characterized in that the supporting member is in contact with the conductive base material layer and power is supplied from a portion in contact therewith.

In the present invention, since the supporting member is in contact with the conductive base material layer, power can be supplied from the contact portion. (12) The invention according to claim 12 provides the image forming apparatus as described in claim 10 or 11, characterized in that the supporting member is a roller.

The present invention illustrates a support member. As the roller of the present invention, for example, the conductive base material layer of the belt photosensitive member is supported on the outer peripheral surface thereof, and by the rotation of the roller,
There is one that moves the belt photoreceptor around. The roller of the present invention can supply power to the conductive base material layer from the outer peripheral surface thereof, for example. (13) According to the invention of claim 13, on the conductive base material layer,
The image forming apparatus according to any one of claims 9 to 12, wherein the photosensitive layer is formed.

In the present invention, since the photosensitive layer is formed on the conductive base material layer, the belt photosensitive member has a simple structure.
Its manufacture is easy. Therefore, the manufacturing cost of the image forming apparatus can be reduced. Further, in the present invention, since no other layer (for example, a vapor deposition layer) is interposed between the conductive base material layer and the photosensitive layer of the belt photoreceptor, the adhesive strength between the conductive base material layer and the photosensitive layer is high. . Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (14) According to the invention of claim 14, in the conductive base material layer, a ten-point average roughness Rz indicating a surface roughness on the side where the photosensitive layer is formed is in the range of 0.01 to 10 μm. The gist of the image forming apparatus according to any one of claims 9 to 13 is.

In the present invention, in the conductive base material layer of the belt photosensitive member, since the roughness on the side where the photosensitive layer is formed is within the above range, the adhesive force between the conductive base material layer and the photosensitive layer is high. Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (15) The invention of claim 15 is characterized in that, in the conductive base material layer, the surface on which the photosensitive layer is formed is roughened by chemical etching treatment. The gist of any of the image forming apparatuses is described.

In the present invention, in the conductive base material layer of the belt photoreceptor, the side on which the photosensitive layer is formed is roughened by chemical etching, so that the adhesive strength between the conductive base material layer and the photosensitive layer is high. Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (16) The invention according to claim 16 is characterized in that, in the conductive base material layer, the surface on the side where the photosensitive layer is formed is roughened by blast treatment.
The gist of the image forming apparatus is any one of 14.

In the present invention, in the conductive base material layer of the belt photosensitive member, the side on which the photosensitive layer is formed is roughened by the blast treatment, so that the adhesive force between the conductive base material layer and the photosensitive layer is high. Therefore, in this belt photoreceptor, the photosensitive layer is less likely to peel off from the conductive base material layer and has excellent durability. (17) The invention of claim 17 is characterized in that the volume resistivity of the conductive base material layer is in the range of 10 ³ to 10 ⁹ Ω · cm. The image forming apparatus is the main point.

In the present invention, since the volume resistivity of the conductive base material layer of the belt photosensitive member is 10 ⁹ Ω · cm or less, for example, a member contacting the belt photosensitive member from the side of the conductive base material layer (for example, Power can be supplied to the belt photosensitive member from a roller supporting the belt photosensitive member.

As a result, the image forming apparatus of the present invention does not need to be provided with an independent power feeding means, so that the apparatus structure can be simplified and the manufacturing cost can be reduced. Further, in the present invention, since the conductive substrate layer of the belt photoreceptor has a volume resistivity of 10 ³ Ω · cm or more, a component (eg, carbon) to be added for imparting conductivity to the conductive substrate layer. ) Can be reduced. Therefore, the belt photosensitive member does not become brittle and has sufficient durability. (18) In the invention of claim 18, the surface resistivity of the conductive base material layer is 2 × 10 ⁴ Ω / □ or more, and the image formation according to any one of claims 9 to 17. The device is the gist.

In the present invention, since the surface resistivity of the conductive base material layer of the belt photosensitive member is 2 × 10 ⁴ Ω / □ or more, a part of the conductive base material layer is the same as the conductive base material layer. Even if it has a potential different from that of other portions, a large current does not flow between the portions having different potentials. (19) The invention of claim 19 is characterized in that the photosensitive layer contains a polycarbonate resin, and the conductive base material layer is made of a polyethylene resin or a polycarbonate resin. The gist of the image forming apparatus is described.

The present invention exemplifies the photosensitive layer and the conductive substrate layer of the belt photoreceptor. In this belt photoreceptor, the photosensitive layer can be positively charged. (20) In the invention of claim 20, the photosensitive layer is formed by laminating an undercoat layer made of polyamide, a charge generation layer, and a charge transport layer, and the conductive base material layer is made of polyamide resin. The gist of the image forming apparatus according to any one of claims 9 to 18 is characterized in that.

The present invention exemplifies the photosensitive layer and the conductive substrate layer of the belt photoreceptor. In this belt photoreceptor, the photosensitive layer can be negatively charged. (21) In the invention of claim 21, the conductive base material layer of the belt photosensitive member has a first potential part having a predetermined first potential and a second potential which is a potential different from the first potential. Second
An electric potential part is included, The said 9 thru | or 20 characterized by the above-mentioned.
The gist of the image forming apparatus is any one of the above.

In the image forming apparatus of the present invention, for example, a potential (first potential) having the same polarity as that of the developer is applied to a part (first potential portion) of the conductive base material layer of the belt photosensitive member so that the developer is The transfer of a visible image composed of In addition, for example, GN may be formed on the other portion (second potential portion) of the conductive base material layer.
A D potential (second potential) can be applied to facilitate formation of an electrostatic latent image at that portion.

In the image forming apparatus of the present invention, for example,
The surface resistivity of the conductive base material layer is a predetermined value (for example, 2 × 10 ⁴
When it is Ω / □ or more, a large current can be prevented from flowing between the first potential portion and the second potential portion. (22) The invention of claim 22 comprises an intermediate transfer member on which a visible image formed by using a developer is transferred onto the belt photosensitive member, and the first potential portion corresponds to the intermediate transfer member. The image forming apparatus according to claim 21, wherein the second potential portion is a portion corresponding to the power supply unit.

In the image forming apparatus of the present invention, for example, the first
By applying a potential having the same polarity as that of the developer to the potential portion, the transfer of the visible image to the intermediate can be facilitated. Further, for example, the second potential portion is connected to the GN by the power feeding means.
A D potential can be applied to facilitate formation of an electrostatic latent image in that portion. (23) The invention of claim 23 is characterized in that a potential gradient control means for controlling a potential gradient is provided between the first potential part and the second potential part. The gist of the image forming apparatus is described.

The image forming apparatus of the present invention is provided with the potential gradient control means so that the first potential section and the second potential section are
Each can be maintained at a predetermined potential. In the image forming apparatus of the present invention, for example, when the surface resistivity of the conductive base material layer is a predetermined value (for example, 2 × 10 ⁴ Ω / □) or more, the first potential part and the potential gradient control means Between and second
It is possible to prevent a large current from flowing between the potential part and the potential gradient control means. (24) The invention of claim 24 is provided with a charging means for charging the photosensitive layer of the belt photosensitive member, and in the first potential section,
An image forming apparatus according to any one of claims 21 to 23 is characterized in that a potential is generated by using the charging unit.

In the image forming apparatus of the present invention, since the electric potential of the first electric potential portion is generated by using the charging means, an independent power source for generating the first electric potential is unnecessary. As a result, this image forming apparatus can have a simple structure and can be manufactured at a reduced cost.

[0036]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a belt photosensitive member and an image forming apparatus of the present invention will be described below. Here, a color laser printer will be described as an image forming apparatus. a) First, the overall configuration of the color laser printer 1 according to the present embodiment will be described with reference to FIG.

I) The color laser printer 1 has a main body casing 3 in which a paper feed section 7 for feeding a paper 5 as a recording medium and a predetermined image is formed on the fed paper 5. The image forming unit 9 and the like are provided. ii) The paper feed unit 7 contacts the paper feed tray 11 in which the papers 5 are stacked and accommodated, and the paper feed roller 1 that contacts the uppermost paper 5 of the paper feed tray 11 and takes out the papers 5 one by one by rotation.
3 and a conveyance roller 15 that conveys the sheet 5 to the image forming position
And a registration roller 17.

This image forming position is a transfer position for transferring a toner image on an intermediate transfer belt 51, which will be described later, onto the sheet 5. In the case of the present embodiment, the intermediate transfer belt 51 and the transfer roller 27, which will be described later, are arranged. The contact position. iii) The image forming unit 9 includes a scanner unit 21, a process unit 23, an intermediate transfer belt mechanism unit 25, a transfer roller 27 as a transfer unit, and a fixing unit 29.

The scanner unit 21 is provided with a laser emitting portion (not shown), a polygon mirror, a plurality of lenses and a reflecting mirror in the central portion of the body casing 3. In the scanner unit 21, the laser beam based on the image data emitted from the laser emitting section is passed or reflected through the polygon mirror, the reflecting mirror and the lens, and the belt photosensitive member 3 of the belt photosensitive member mechanism section 31 which will be described later.
Irradiate the surface of No. 3 by high speed scanning.

The process section 23 includes a plurality (four) of developing cartridges 35, a belt photosensitive member mechanism section 31, and the like. The four developing cartridges 35 are, for each color, a yellow developing cartridge 35Y containing a yellow toner, a magenta developing cartridge 35M containing a magenta toner, a cyan developing cartridge 35C containing a cyan toner, and a black toner. Each of the black developing cartridges 35K in which the
On the rear side of the main body casing 3, they are sequentially arranged in parallel from the bottom to the top at predetermined intervals in the vertical direction.

Each developing cartridge 35 is provided with a developing roller 37, a layer thickness regulating blade (not shown), a supply roller, a toner accommodating portion, etc., and each developing roller 35 comes into contact with the surface of a belt photosensitive member 33 described later or It is configured to be movable in the horizontal direction by a separating solenoid (not shown) so as to be separated.

The developing roller 37 has a metal roller shaft,
A roller made of an elastic member made of a conductive rubber material is covered. More specifically, the roller of the developing roller 37 is a conductive urethane rubber containing carbon fine particles,
An elastic roller portion made of silicone rubber or EPDM rubber and the surface of the roller portion are covered.
It is formed of a two-layer structure including a coat layer, which is mainly composed of urethane rubber, urethane resin, polyimide resin and the like. A predetermined developing bias is applied to the developing roller 37 with respect to the belt photosensitive body 33.

The toner accommodating portion of each developing cartridge 35 accommodates a positively chargeable non-magnetic single-component spherical polymerized toner as a developer of each color of yellow, magenta, cyan and black. Then, the toner is supplied to the developing roller 37 by the rotation of the supply roller, positively frictionally charged between the supply roller and the developing roller 37, and the toner supplied on the developing roller 37 is With the rotation of the developing roller 3, it enters between the layer thickness regulating blade and the developing roller 37, where it is further triboelectrically charged and becomes a developing roller 3 as a thin layer having a constant thickness.
Carried on 7.

The belt photoconductor mechanism section 31 includes a first belt photoconductor roller 39, a second belt photoconductor roller 41, a third belt photoconductor roller 43, and these first belt photoconductor roller 39 and second belt photoconductor. The roller 41 and the belt photoreceptor 33 wound around the third belt photoreceptor roller 43, a belt photoreceptor charger 45, a potential adder 47, and a potential gradient controller 49 are provided. The configuration of the belt photoconductor mechanism unit 31 will be described later in detail.

The intermediate transfer belt mechanism portion 25 is arranged on the front side of the belt photosensitive member mechanism portion 31, and is substantially disposed on the second belt photosensitive member roller 41 via the belt photosensitive member 33 and an intermediate transfer belt 51 described later. The first intermediate transfer belt roller 53 and the first intermediate transfer belt roller 5 which are arranged to face each other.
A second intermediate transfer belt roller 55 disposed obliquely below and to the front of the second intermediate transfer belt roller 55.
Third intermediate transfer belt roller 57, which is arranged to face each other through
And an intermediate transfer belt 51 wound around the outer periphery of the first intermediate transfer belt roller 53 to the third intermediate transfer belt roller 57.

The intermediate transfer belt 51 is an endless belt made of a resin such as conductive polycarbonate or polyimide in which conductive particles such as carbon are dispersed. The first intermediate transfer belt roller 53 to the third intermediate transfer belt roller 57 are arranged in a triangular shape, and the intermediate transfer belt 51 is wound around them. The first motor is driven by a main motor (not shown).
While the intermediate transfer belt roller 53 is rotationally driven,
By the second intermediate transfer belt roller 55 and the third intermediate transfer belt roller 57 being driven, the intermediate transfer belt 5
1 is the first intermediate transfer belt roller 53 to the third
It is rotated between the intermediate transfer belt rollers 57 (clockwise movement).

The transfer roller 27 is arranged so as to face the third intermediate transfer belt roller 57 of the intermediate transfer belt mechanism 25 with the intermediate transfer belt 51 interposed therebetween, and a roller made of a conductive rubber material on a metal roller shaft. Is covered and is rotatably supported. This transfer roller 27
Is a standby position separated from the intermediate transfer belt 51 by an unillustrated transfer roller contact / separation mechanism, and the intermediate transfer belt 5
It is configured to be movable to a transferable position close to 1. The standby position and the transferable position are located on opposite sides of the conveyance path 59 of the sheet 5 with the conveyance path 59 interposed therebetween, and at the transferable position, the conveyance path 5 is formed between the sheet 5 and the intermediate transfer belt 51.
It is configured to press the sheet 5 passing through 9.

As will be described later, the transfer roller 27 is located at the standby position while the visible image of each color is sequentially transferred to the intermediate transfer belt 51, and all the visible images are transferred to the belt photosensitive member. When the color image is transferred from 33 to the intermediate transfer belt 51 and a color image is formed on the intermediate transfer belt 51, it is positioned at the transfer enable position.

The transfer roller 27 is applied with a predetermined transfer bias to the intermediate transfer belt 51 at a transferable position by a transfer bias applying circuit (not shown). The fixing unit 29 is disposed on the upper side of the intermediate transfer belt mechanism unit 25, and is provided on the heating roller 61, the pressing roller 63 that presses the heating roller 61, and the heating roller 61 and the downstream side of the pressing roller 63. Pair of conveying rollers 65
It has and. The heating roller 61 has an outer layer made of silicon rubber and an inner layer made of metal, and includes a halogen lamp for heating.

B) Next, the belt photosensitive member mechanism portion 31 of the image forming portion 9 will be described in more detail. i) The first belt photoconductor roller 39 is arranged on the front side of the four developing cartridges 35 so as to face each other, and is arranged below the yellow developing cartridge 35Y located at the lowest position. The first belt photosensitive roller 39 is a roller that is driven and rotated.

The second belt photosensitive member roller 41 is
It is arranged above the belt photosensitive roller 39 in the vertical direction and above the black developing cartridge 35K located at the uppermost position. The second belt photoconductor roller 41 is rotationally driven by driving a main motor (not shown).

The third belt photosensitive roller 43 is the same as the first belt.
The belt photoconductor roller 39 is disposed diagonally above and on the front side.
The third belt photoconductor roller 43 is a roller that is driven and rotated. Therefore, these first belt photoconductor rollers 3
9, the second belt photosensitive member roller 41, and the third belt photosensitive member roller 43 are arranged in a triangular shape.

The second photosensitive belt roller 41 is applied with a potential of +300 V by the power supply of the belt photosensitive member charger 45 by the potential adding device 47 arranged in the vicinity thereof. The first belt photoconductor roller 39 and the third belt photoconductor roller 43 are made of a conductive material such as aluminum, and the base material layer 67 of the belt photoconductor 33, which will be described later, is used.
And is connected to a GND terminal (not shown). That is, the first belt photoconductor roller 39 and the third belt photoconductor roller 43 serve as power feeding means and keep the potential of the belt photoconductor 33 at a position where they are in contact with each other at GND.

Ii) The belt photoconductor 33 includes a first belt photoconductor roller 39, a second belt photoconductor roller 41, and a third belt photoconductor roller 41.
It is wound around the belt photosensitive roller 43. Then, the second belt photoconductor roller 41 is rotationally driven, and the first belt photoconductor roller 39 and the third belt photoconductor roller 43 are driven, whereby the belt photoconductor 33
Moves around (turns counterclockwise).

As shown in FIG. 2, the belt photosensitive member 33 has a base material layer (conductive base material layer) 67 having a thickness of 0.15 mm.
And an endless belt having a photosensitive layer 69 having a thickness of 25 μm on one side thereof. The base layer 67 is made of polyethylene resin, and the photosensitive layer 69 is made of a polycarbonate resin photoreceptor.

The volume resistivity of the base material layer 67 is 1 × 1.
The surface resistance is 0 ⁵ Ω · cm and the surface resistance is 1 × 10 ⁵ Ω / □. iii) As shown in FIG. 1, the belt photoconductor charger 45 is located below the belt photoconductor mechanism unit 31 and on the upstream side of the portion where the scanner unit 21 exposes the belt photoconductor 33.
In the vicinity of the first belt photoconductor roller 39, the first belt photoconductor roller 39 is disposed so as to face the belt photoconductor 33 at a predetermined interval so as not to contact the belt photoconductor 33. The belt photoconductor charger 45 is a scorotron type charger for positive charging that generates corona discharge from a charging wire such as tungsten, and charges the surface of the belt photoconductor 33 uniformly in a positive polarity. It is configured.

Iv) The potential gradient controller 49 is located between the second belt photoconductor roller 41 and the first belt photoconductor roller 39, and above the black developing cartridge 35K, the base material layer of the belt photoconductor 33. I am in contact with 67. This potential gradient controller 49 is
The potential of the base material layer 67 is dropped to GND.

C) Next, a method of manufacturing the belt photosensitive member 33 will be described with reference to FIG. The base material layer 67 is formed with a predetermined size, and one side thereof is roughened to a ten-point average roughness Rz of 1 μm by chemical etching. The base material layer 67 is fixed along the outer periphery of the cylindrical holder 101 so as not to bend. At this time, the side roughened by the chemical etching is set to be the outer side.

Photosensitive solution 103 in which a photosensitive material is dissolved in a solvent
Is filled in the container 105. This light-sensitive material is a light-sensitive material made of a polycarbonate resin, and is a commonly used material. In the holder 101, the entire base material layer 67 is the photosensitive solution 103.
Place in container 105 until hidden.

The holder 101 is pulled up at a constant speed. Then, the solvent of the photosensitive liquid 103 is evaporated on the base material layer 67 to form a photosensitive layer 69 made of a photosensitive material. It should be noted that the higher the speed at which the holder 101 is pulled up, the thicker the photosensitive layer 69 becomes. d) Next, the operation of the color laser printer 1 will be described.

Of the papers 5 accommodated in the paper feed tray 11 of the paper feed unit 7, the paper feed roller 13 is pressed to the uppermost paper, and the paper 5 is moved by the rotation of the paper feed roller 13. It is taken out sheet by sheet. The taken-out sheet 5 is fed to the image forming position by the conveyance roller 15 and the registration roller 17. The registration roller 17 performs a predetermined registration on the fed paper 5.

The surface of the belt photoconductor 33 is uniformly positively charged by the belt photoconductor charger 45, and then exposed by high-speed scanning of the laser beam from the scanner unit 21 based on the image data. Since the charging is eliminated in the exposed portion, an electrostatic latent image in which a positively charged portion and an uncharged portion are arranged is formed on the surface of the belt photoreceptor 33 according to the image data. To be done.

At this time, the first belt photoconductor roller 39 and the third belt photoconductor roller 43 as power feeding means feed power to the base material layer 67 of the belt photoconductor 33 with which they abut,
The potential of the contact portion is maintained at GND. The yellow developing cartridge 35Y of the developing cartridges 35 is moved forward in the horizontal direction by a separating solenoid (not shown) on the belt photosensitive member 33 on which the electrostatic latent image is formed.
The developing roller 37 of the yellow developing cartridge 35Y,
The belt photoconductor 33 on which the electrostatic latent image is formed is brought into contact.

The yellow toner contained in the yellow developing cartridge 35Y is positively charged, and adheres only to the uncharged portion on the belt photoconductor 33. As a result, a yellow visible image is formed on the belt photoconductor 33. At this time, the magenta developing cartridge 3
5M, the cyan developing cartridge 35C, and the black developing cartridge 35K are moved rearward in the horizontal direction by the separating solenoid to be separated from the belt photoconductor 33.

The yellow visible image formed on the belt photosensitive member 33 is transferred onto the surface of the intermediate transfer belt 51 when it faces the intermediate transfer belt 51 due to the movement of the belt photosensitive member 33. At this time, + 300V is applied to the second belt photoconductor roller 41 by the power source of the belt photoconductor charger 45.
The potential of is added. Then, the photosensitive layer 69 in the vicinity of the second belt photosensitive roller 41 also passes through the conductive base material layer 67,
The potential is + 300V. Therefore, a repulsive force is generated between the positively charged yellow toner and the photosensitive layer 69, and the toner is easily transferred to the intermediate transfer belt 51.

Similarly to the above, with respect to magenta, an electrostatic latent image is formed on the belt photosensitive member 33, a magenta visible image is subsequently formed, and magenta is formed on the intermediate transfer belt 51. Transfer the visual image. That is, an electrostatic latent image is formed again on the belt photosensitive member 33, and then the magenta developing cartridge 35M is moved forward by the separating solenoid in the horizontal direction to cause the developing roller 37 of the magenta developing cartridge 35M to move to the belt photosensitive member. The yellow developing cartridge 35Y, the cyan developing cartridge 35C, and the black developing cartridge 35 are brought into contact with the body 33.
By moving K to the rear in the horizontal direction by the separating solenoid and separating it from the belt photosensitive member 33, a visible image of magenta is formed on the belt photosensitive member 33 only by the magenta toner contained in the magenta developing cartridge 35M. When the visible image of magenta is formed, a yellow visible image is already formed when the visible image of magenta faces the intermediate transfer belt 51 due to the movement of the belt photoreceptor 33 in the same manner as described above. The image is transferred onto the intermediate transfer belt 51, which has been transferred.

Such a similar operation is repeated by the cyan toner contained in the cyan developing cartridge 35C and the black toner contained in the black developing cartridge 35K, whereby a color image is formed on the intermediate transfer belt 51. It is formed.

In the color image formed on the intermediate transfer belt 51, the paper 5 is the intermediate transfer belt 51 and the transfer roller 2.
While passing between the sheet and the sheet 7, the sheets are collectively transferred onto the sheet 5 by the transfer roller 27 located at the transferable position. The heating roller 61 of the image forming unit 9 heat-fixes the color image transferred on the sheet 5 while the sheet 5 passes between the heating roller 61 and the pressing roller 63.

Then, the sheet 5 on which the color image has been heat-fixed in the fixing section 29 is conveyed by the conveying roller 65 to the pair of sheet discharging rollers 71. Paper ejection roller 7
The sheet 5 sent to the sheet 1 is discharged onto the sheet discharge tray 73 formed on the upper portion of the main body casing 3 by the sheet discharge rollers 71.

E) The effects of the belt photosensitive member 33 and the color laser printer 1 of this embodiment will be described. The belt photoreceptor 33 of the present embodiment includes a base material layer 67 and a photosensitive layer 69. Like the conventional belt photoreceptor 33, a vapor deposition layer is provided between the base material layer and the photosensitive layer, or It is not necessary to provide a conductive layer on the vapor deposition layer.

Therefore, the belt photoreceptor 33 is easy to manufacture, and the manufacturing cost can be reduced. In the belt photoreceptor 33 of the present embodiment, the photosensitive layer 6
No. 9 is directly bonded onto the base material layer 67, and unlike the conventional case, since a vapor deposition layer having low mechanical strength is not interposed between the photosensitive layer and the base material layer, the photosensitive layer 69 and the base material layer The close contact with 67 is high. Therefore, the photosensitive layer 69 is unlikely to be peeled off from the base material layer 67, and the durability of the belt photoreceptor 33 is high.

Further, in this embodiment, since the photosensitive layer 69 is provided after the surface of the base material layer 67 is roughened by chemical etching, the adhesiveness between the base material layer 67 and the photosensitive layer 69 is higher. Therefore, the photosensitive layer 69 is less likely to be peeled off from the base material layer 67, and the durability of the belt photoreceptor 33 is further enhanced.

In the present embodiment, power is supplied to the base material layer 67 of the belt photoconductor 33 from the first belt photoconductor roller 39 and the third belt photoconductor roller 43. It is not necessary to separately provide a brush feeder for feeding 33. As a result, the color laser printer 1 according to the present embodiment can have a simplified structure and can reduce manufacturing costs. Also,
The color laser printer 1 can be miniaturized.

In this embodiment, since the volume resistivity of the base material layer of the belt photosensitive member 33 is 10 ³ Ω or more, the amount of the carbon material to be added in order to make the base material layer 67 conductive is small. can do. As a result, the belt photosensitive member 33 does not become brittle and has sufficient durability.

Further, in this embodiment, the belt photosensitive member 3
The volume resistivity of the base material layer 67 of 3 is 10 ⁹Ω or less
And the first belt photoconductor roller 39 and the third belt photoconductor
Power can be received from the roller 43. In the present embodiment, the base material layer 67 of the belt photoreceptor 33 is
Surface resistance is 2 × 10^FourAs described above, the potential gradient controller
49 and the second belt photoconductor roller 41 are short-circuited.
There is no end.

That is, the base material layer 67 of the belt photosensitive member 33.
As described above, the base layer 67 has the GND potential at the portion in contact with the potential gradient controller 49 and the potential of +300 V at the portion in contact with the second belt photosensitive roller 41. Since the surface resistance of No. 2 is sufficiently large, a large current does not flow between the potential gradient controller 49 and the second belt photosensitive roller 41.

It should be noted that the present invention is not limited to the above embodiment, and can be implemented in various forms without departing from the gist of the present invention. In the embodiment, the surface of the base material layer 67 (the photosensitive layer 6
Blasting may be used as a method of roughening the surface (the surface on the side to be bonded to 9).

In the above embodiment, the material forming the base material layer 67 may be, for example, a polycarbonate resin. Further, the belt photosensitive member 33 in the above-described embodiment is
It may be negatively charged. In that case, for example, the photosensitive layer 69 is formed by laminating an undercoat layer made of polyamide, a charge generation layer, and a charge transport layer, and the base material layer 67 is made of a polyamide resin. can do.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a color laser printer according to an embodiment.

FIG. 2 is an explanatory diagram showing a configuration of a belt photosensitive member according to the embodiment.

FIG. 3 is an explanatory diagram showing a method of manufacturing a belt photosensitive member according to the embodiment.

FIG. 4 is an explanatory diagram showing a configuration of a conventional belt photosensitive member.

[Explanation of symbols]

1 ... Color laser printer 9 ... Image forming unit 25 ... Intermediate transfer belt mechanism section 27 ... Transfer roller 31 ... Belt photoconductor mechanism 33 ... Belt photoreceptor 35 ... Developing cartridge 37 ... Developing roller 39 ... First belt photosensitive roller 41 ... Second belt photosensitive roller 43 ... Third belt photosensitive roller 45 ... Belt photoconductor charger 47 ... Potential adder 49 ... Potential gradient controller 51 ... Intermediate transfer belt 53 ... First intermediate transfer belt roller 55 ... Second intermediate transfer belt roller 57 ... Third intermediate transfer belt roller 67 ... Base material layer 69 ... Photosensitive layer

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 21/00 350 G03G 21/00 350 F term (reference) 2H035 CA05 CB06 CZ01 2H068 AA13 AA43 AA55 AA58 AA59 BB04 BB25 BB28 EA05 2H200 FA13 GA16 GA24 GA28 GA34 GA47 GA50 GB22 GB25 HA02 HA12 HA28 HB12 JA02 JB20 JC03 JC07 LC03 LC05 LC10 NA09

Claims (24)

[Claims] 1. A belt photoreceptor for forming an electrostatic latent image, comprising a conductive base material layer and a photosensitive layer, wherein the conductive base material layer has a volume resistivity of 10 ³ to 10 ^9. Ω · cm
A belt photosensitive member characterized by being in the range of. 2. The surface resistivity of the conductive base material layer is 2 × 1.
The belt photosensitive member according to claim 1, wherein the belt photosensitive member has a resistance of 0 ⁴ Ω / □ or more. 3. A belt photosensitive member, wherein the photosensitive layer is formed on the conductive base material layer. 4. The ten-point average roughness Rz, which indicates the surface roughness on the side where the photosensitive layer is formed, in the conductive base material layer,
The belt photosensitive member according to any one of claims 1 to 3, which is in a range of 0.01 to 10 µm. 5. The conductive base material layer according to claim 1, wherein the side on which the photosensitive layer is formed is roughened by a chemical etching process. Belt photoreceptor. 6. The belt according to claim 1, wherein a surface of the conductive base material layer on which the photosensitive layer is formed is roughened by blasting. Photoconductor. 7. The photosensitive layer contains a polycarbonate resin, and the conductive substrate layer is made of a polyethylene resin or a polycarbonate resin.
7. The belt photosensitive member according to any one of to 6. 8. The photosensitive layer is formed by laminating an undercoat layer made of polyamide, a charge generation layer, and a charge transport layer, and the conductive base material layer is made of a polyamide resin. The belt photoreceptor according to any one of claims 1 to 6. 9. An image forming apparatus including a belt photosensitive member for forming an electrostatic latent image, wherein the belt photosensitive member is formed by directly or indirectly laminating a conductive base material layer and a photosensitive layer, An image forming apparatus comprising: a power supply unit that supplies power to the conductive base material layer from a side where the photosensitive layer is not formed. 10. The image forming apparatus according to claim 9, further comprising a support member that supports the belt photoconductor, and the support member is the power supply unit. 11. The image forming apparatus according to claim 10, wherein the supporting member is in contact with the conductive base material layer, and power is supplied from a portion in contact therewith. 12. The image forming apparatus according to claim 10, wherein the support member is a roller. 13. The image forming apparatus according to claim 9, wherein the photosensitive layer is formed on the conductive base material layer. 14. A ten-point average roughness Rz showing a surface roughness of a side of the conductive base material layer on which the photosensitive layer is formed.
Is in the range of 0.01 to 10 μm. 14. The image forming apparatus according to claim 9, wherein 15. The conductive base material layer according to claim 9, wherein a surface of the conductive base material layer on which the photosensitive layer is formed is roughened by a chemical etching treatment. Image forming apparatus. 16. The image according to claim 9, wherein a surface of the conductive base material layer on which the photosensitive layer is formed is roughened by a blast treatment. Forming equipment. 17. The volume resistivity of the conductive base material layer is 10
The image forming apparatus according to any one of claims 9 to 16, wherein the image forming apparatus is in the range of ³ to 10 ⁹ Ω · cm. 18. The surface resistivity of the conductive base material layer is 2 ×.
10. The method according to claim 9, wherein the resistance is 10 ⁴ Ω / □ or more.
The image forming apparatus according to any one of 1 to 17. 19. The method according to claim 9, wherein the photosensitive layer contains a polycarbonate resin, and the conductive substrate layer is made of a polyethylene resin or a polycarbonate resin.
The image forming apparatus according to any one of 1 to 18. 20. The photosensitive layer is formed by laminating an undercoat layer made of polyamide, a charge generation layer, and a charge transport layer, and the conductive base material layer is made of a polyamide resin. The image forming apparatus according to any one of claims 9 to 18. 21. The conductive substrate layer of the belt photosensitive member,
The first potential part having a predetermined first potential and the second potential part having a second potential which is a potential different from the first potential are included. The image forming apparatus described. 22. An intermediate transfer member, to which a visible image formed by using a developer is transferred, is provided on the belt photosensitive member, wherein the first potential portion is a portion corresponding to the intermediate transfer member, The image forming apparatus according to claim 21, wherein the second potential portion is a portion corresponding to the power supply unit. 23. The image formation according to claim 21 or 22, further comprising: a potential gradient control means for controlling a potential gradient between the first potential section and the second potential section. apparatus. 24. A charging unit for charging a photosensitive layer of the belt photosensitive member, wherein the first potential section uses the charging unit to generate a potential, and any one of the above-mentioned items 21 to 23. An image forming apparatus according to claim 2.