JP2000098702A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably obtain an excellent image by preventing toner from being splashed in an image forming device constituted so that the image is obtained by making developer (toner) passed through an aperture part directly fly toward a recording medium by controlling the voltage of the control electrode of the aperture part based on an electric signal by utilizing an electric field generated at the aperture part. SOLUTION: The intermediate recording medium 6 being the recording medium is formed of a conductive member. Then, a toner image formed by making the electrified toner (black toner 7K) fly toward the medium 6 from a developing sleeve 21 through the aperture part 20a by controlling the voltage applied to the sleeve 21, the control electrode 23a and the medium 6 is temporarily fixed on the medium 6 once by a first heating body 12a being the temporal fixing means. Thereafter, it is transferred and fixed on a transfer material. Thus, since the toner is prevented from being splashed, the excellent image is stably obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an image forming apparatus applicable to a printer, a facsimile, a copying machine, and the like.
In particular, by using the electric field generated in the opening to control the voltage of the control electrode in the opening by an electric signal, the developer (hereinafter referred to as “toner”) passing through the opening directly flies onto the recording medium to form an image. The present invention relates to an obtained image forming apparatus.

[0002]

2. Description of the Related Art As a developer used in an image forming apparatus of an electrophotographic system or an electrostatic recording system conventionally employed in copying machines, printers, etc., a toner containing a coloring pigment in particles is used. The so-called dry development method has become mainstream.

[0003] The reason for this is that the dry developing method is advantageous in handling and providing a toner charging mechanism as compared with the wet developing method which has been used before, and that the developing method on the developing sleeve which carries and conveys the toner is used. The toner retention can be adjusted using magnetic force, electrostatic force, or van der Waals force, and has advantages such as easy control of image quality improvement such as reduction of so-called ground fog. .

For example, as the above-mentioned electrostatic recording method, US Pat. No. 3,689,935, JP-A-57-19763, and Japanese Patent Publication No. 1-503221 disclose a plurality of openings for forming pixels. A method is disclosed in which toner is controlled to pass through an opening by electrostatically controlling the toner to selectively fly on a transfer material such as recording paper. In this method, since the toner is controlled to fly from the opening, the scattering of the toner can be suppressed. Further, since no photoreceptor is used, the device configuration can be simplified, and the device can be reduced in size and cost.

[0005] Japanese Patent Application Laid-Open No. Hei 7-132624 discloses an apparatus using an intermediate recording medium. This is because the control electrode in the opening and the intermediate recording medium (JP-A-7-13264)
The toner is controlled to pass through the opening by an electric field between the base electrodes on the back of the transfer belt.
Once a toner image is formed on the intermediate recording medium, the toner image on the intermediate recording medium is transferred to a final recording medium to obtain a final image. In this method, since the intermediate recording medium during image formation is always the same, a good image can be stably obtained even when various recording media are used.

[0006]

However, in the above conventional examples described in U.S. Pat. No. 3,689,935, JP-A-57-19763, and Japanese Patent Publication No. 1-503221, an image is formed depending on the type of recording paper. In contrast, good images were not always obtained stably.

Further, in the above-described conventional example described in Japanese Patent Application Laid-Open No. Hei 7-132624, an insulating material such as polyimide is used as the transfer belt, so that when a toner image is formed in multiple layers, the image may be disturbed. there were. For example, when a multi-image is formed on a transfer belt to obtain a multi-color image, the image may be scattered under the influence of the toner image at the preceding stage.

SUMMARY OF THE INVENTION In view of the above problems, the present invention suppresses and prevents toner scattering even when various recording media are used, does not cause image scattering, and can stably obtain good images. The purpose is to provide.

[0009]

In order to achieve the above object, the present invention provides an opening, a control electrode disposed around the opening, fine particles, a charging means for charging the fine particles, A supply unit for supplying the fine particles to the opening, and the charged fine particles supplied by the supply unit are electrostatically controlled by applying a voltage to the control electrode, so that the opening is formed. In an image forming apparatus for forming a fine particle image on a recording medium by selectively passing and flying, a fine particle formed on the recording medium by forming the recording medium with a conductive member and flying from the opening portion It is characterized in that it has a hypothetical attachment means for hypothetically attaching an image on the recording medium.

A rotatable fine particle carrier for supporting charged fine particles on a surface thereof, a relatively moving recording medium disposed opposite to the fine particle carrier at a predetermined interval, and the fine particle carrier and the recording medium. A plurality of openings formed between the medium and a medium, and electrodes provided around each of the openings, and the charged fine particles supplied by the supply unit are applied to the control electrode by applying a voltage to the control electrode. An image forming apparatus, wherein the fine particle image is formed on the recording medium by selectively passing and flying through the opening by electrostatically controlling, and then the fine particle image is transferred to a transfer material. Is formed of a conductive member, and by applying a voltage to the recording medium using the recording medium as a counter electrode, the charged fine particles are caused to fly from above the fine particle carrier to form the fine particles formed on the recording medium. It is characterized by having a temporary fixing means for temporarily fixing the child image on the recording medium.

[0011] Further, the present invention is characterized in that the fine particle image assumed on the recording medium is transferred by heating and pressing to a transfer material and fixed.

Further, the hypothetical attachment means is characterized in that the fine particle image is assumed to be applied by applying heat to the recording medium.

[0013] The hypothetical attachment means is characterized in that the fine particle image is hypothetically attached to the recording medium by an adhesive force.

Further, the opening is formed in a circular shape.

The opening has a slit shape formed in a direction perpendicular to the moving direction of the recording medium, and the electrodes divided so as to face both sides of the slit-shaped opening are provided side by side. It is characterized by doing.

Further, the recording medium is characterized in that a conductive release layer is formed on a conductive substrate.

Further, a plurality of the fine particle carriers are arranged along the moving direction of the recording medium, and the fine particles of an arbitrary color carried on each of the fine particle carriers are sequentially flown onto the recording medium to produce color fine particles. It is characterized by forming an image.

Further, the apparatus includes an opening, a control electrode disposed around the opening, fine particles, charging means for charging the fine particles, and supply means for supplying the fine particles to the opening. Controlling the charged fine particles supplied by the supply means electrostatically by applying a voltage to the control electrode, thereby selectively passing and flying through the opening to form a fine particle image on a recording medium. In the image forming apparatus, the fine particles are a microcapsule toner containing an adhesive material, and the image formed by the microcapsule toner formed by flying from the opening is formed on the recording medium by the adhesive. It is characterized in that, after being adhered by the adhesive force of the partial material, the image is simultaneously transferred and fixed to a transfer material.

(Operation) According to the structure of the present invention, since the recording medium is formed of a conductive member, the electric field during image formation is hardly affected by the electric charge of the fine particles on the recording medium and is stable. As a result, a good image can be formed.
In particular, a very large effect is exhibited when forming multiple images sequentially.

Further, by immediately assuming the fine particle image formed by flying the charged fine particles onto the recording medium from the fine particle carrier through the opening, the disturbance of the fine particle image is prevented and the scattering of the image is prevented. Can be.

Further, since the fine particles are made to fly only from the opening to the place where the image is to be formed, and the flying fine particles are immediately assumed, the scattering of the toner is prevented, and the contamination of the apparatus and the environment is prevented. it can.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment FIG. 1 is a schematic configuration diagram showing an image forming apparatus (a full-color digital electrophotographic copying machine in this embodiment) according to the present embodiment.

In FIG. 1, reference numeral 1 denotes an apparatus main body (printer unit), and 2 denotes an image reading apparatus (image scanner) mounted on the apparatus main body 1.

In the image reading apparatus 2, reference numeral 3 denotes a fixed platen glass. The document G is placed on the platen glass 3 with the surface on which the document G is to be copied facing downward, and the platen 4 is placed on the platen. Put on and set. Reference numeral 5 denotes an image reading unit in which a document irradiation lamp 5a, a short focus lens array 5b, a CCD sensor 5c, and the like are arranged.

When the copy button (not shown) is pressed, the image reading unit 5 moves from the home position on the lower side of the original table glass 3 to the right side along the lower surface of the original table glass 3 on the lower side of the original table glass 3 by pressing a copy button. It is driven forward and when it reaches a predetermined reciprocating end point, it is driven backward and returned to its initial home position.

In the forward driving process of the image reading unit 5, the downward image surface of the original G on the original platen glass 3 is sequentially illuminated and scanned by the original irradiation lamp 5a from the left side to the right side in FIG. Is reflected and imaged on the CCD sensor 5c by the short focus lens array 5b.

The CCD sensor 5c includes a CCD light receiving unit (not shown), a transfer unit, and an output unit. The CCD light receiving unit converts an optical signal into a charge signal, and the transfer unit sequentially synchronizes with a clock pulse. The signal is transferred to the output unit, and the output unit converts the charge signal into a voltage signal, amplifies the voltage signal, lowers the impedance, and outputs the voltage signal. The analog signal thus obtained is converted into a digital signal by well-known image processing and output to the apparatus body (printer unit) 1 side. That is, the image information of the document G is photoelectrically read by the image reading device (image scanner) 2 as a time-series electric digital pixel signal (image signal).

On the other hand, in the apparatus body (printer section) 1,
A conductive intermediate recording medium (endless belt) 6 as a recording medium, and a developing device that develops black toner 7K as fine particles below the intermediate recording medium 6 in order from the upstream side in the moving direction a of the intermediate recording medium 6 8K, a developing device 8C for developing the cyan toner 7C, a developing device 8M for developing the magenta toner 7M, a developing device 8Y for developing the yellow toner 7Y, a sheet feeding unit 9 containing the transfer material P, and the like.

The intermediate recording medium 6 is suspended around a driving roller 10, a driven roller 11, and a second heating member 13 described later, and the lower surface of the belt moves in the direction of arrow a (clockwise). Both ends of the drive roller 10 and the driven roller 11 are rotatably supported by bearings (not shown).

Further, the developing device 8K in the intermediate recording medium 6,
First heaters 12a, 12b, 12c, 12d (thermal heaters) provided respectively are arranged at positions facing 8C, 8M, 8Y. A pressure roller 14 is provided via a transfer belt 6 at the transfer fixing section さ れ where the second heating element 13 is disposed. Further, a cleaning member 15 such as a felt pad is provided outside the intermediate recording medium 6.

Each of the developing devices 8K, 8C, 8M, and 8Y has a developing container 20K as shown in FIG.
A drum-shaped rotatable developing sleeve 21 as a toner carrier for carrying the black toner 7K on the surface is provided therein. The developing sleeve 21 is formed of a non-magnetic material such as aluminum or stainless steel. A power supply 22 is connected to the developing sleeve 21.

An aperture electrode 23 is provided around the plurality of openings 20a formed in the upper portion of the developing container 20 so as to face the first heating element 10d. As shown in FIG. 3, the rows of the openings 20 a of the developing container 20 are arranged in a direction crossing the conveying direction of the intermediate recording medium 6 (from right to left in FIG. 3), and are inclined. ing.

As shown in FIGS. 2 and 3, the aperture electrode 23 is provided with a control electrode 23b on an insulating substrate 23a so as to surround each opening 20a.
A power supply 2 is connected to each control electrode 23b through an electrode pattern 24.
5 is connected. The surface of the control electrode 23b is the insulating layer 2
3c. The power supply 26 is also connected to the intermediate recording medium 6.

Here, an example of a method for forming the aperture electrode 23 will be described with reference to FIG.

The insulating substrate 23a is, for example, a polyimide having a thickness of 50 μm. A circular pattern corresponding to the opening 20a is formed on a copper foil having a thickness of 18 μm previously laminated on the surface by a known photolithographic method. The electrode 23b is formed.

The insulating layer 23c has a thickness of 25 μm.
After laminating the polyimide film, the opening 20 is irradiated with an excimer laser or a carbon dioxide laser.
a can be formed. In addition, as the method for forming the aperture electrode 23, another method such as electroforming can be used.

A toner layer regulating blade 27 is provided on the inner wall of the developing container 20 to regulate the thickness of the toner layer carried on the developing sleeve 21.

Next, an image forming operation by the above-described image forming apparatus will be described by taking a full color mode as an example.

First, as described above, by controlling the voltage applied to the control electrode 23b of the aperture electrode 23 in accordance with the black image signal of the original G, the toner flies from the developing sleeve 21 onto the intermediate recording medium 6, and the black Form a toner image.

Here, the electrostatic toner discharge control by the control electrode 23b will be described.

The applied voltage from the power supply 25 to the control electrode 23b during ON control is Vc, and the applied voltage during OFF control is V
c ′, the developing sleeve 21 as a back electrode from the power source 22
Assuming that the applied voltage to the intermediate recording medium 6 as the counter electrode from the power supply 26 is Vo, Vo>Vc>Vb> Vc ′ or Vo <Vc <Vb <V
c ′ is satisfied.

For example, using a negatively charged toner (black toner 7K), the applied voltage Vc = + 200 V and Vc ′ = − 200 V from the power supply 25 to the control electrode 23 b, and the applied bias voltage Vb from the power supply 22 to the sleeve 21 = 0V
(Earth), the bias voltage Vo applied from the power supply 26 to the intermediate recording medium 6 is set to + 2000V.

Then, the toner (black toner 7K) on the developing sleeve 21 is discharged to the intermediate recording medium 6 through the opening 20a corresponding to the control electrode 23b to which +200 V is applied from the power supply 25. On the other hand, power supply 25
The negatively charged toner (black toner 7K) is repelled by the control electrode 23b to which 0 V is applied, and is not discharged to the intermediate recording medium 6 side through the opening 20a.

As described above, by controlling the flight (release) of the toner carried on the developing sleeve 21 to the intermediate recording medium 6, a toner image can be formed on the intermediate recording medium 6.

Then, the first heating element 12a is controlled in advance to a heater set temperature described later. As a result, when the black toner image is transferred onto the intermediate recording medium 6, the toner image is tentatively deposited on the intermediate recording medium 6 by heating by the first heating element 12a. Since the intermediate recording medium 6 is conductive, even if black toner is formed (transferred) on the intermediate recording medium 6 in multiple layers, the electric field between the developing device 8K and the intermediate recording medium 6 causes black image formation (transfer). Since the toner image is hardly affected by the charge of the toner image, a good image is formed.

The toner (black toner 7K) on the sleeve 21 from the control electrode 23b through the opening 20a.
Is caused to fly only to a place where an image is to be formed on the transfer belt 6, and the flying toner is immediately assumed, so that the scattering of the toner can be prevented, and the contamination of the apparatus and the environment can be prevented. it can.

Then, the intermediate recording medium 6 moves to the position of the developing device 8C, and a cyan toner image is formed on the intermediate recording medium 6 according to the cyan image signal in the same manner as described above. Is done.

Here, since the intermediate recording medium 6 is conductive,
Since the electric field between the developing device 8C and the intermediate recording medium 6 is hardly affected by the electric charge of the black toner image at the preceding stage during the cyan image formation (transfer), a good image is faithfully formed according to the cyan image signal. You.

At this time, since the previously formed black toner image is assumed on the intermediate recording medium 6, the image is not disturbed. Therefore, a good image can be stably formed without scattering of the image.

Subsequently, the above-described process is applied to the developing device 8 for magenta and yellow colors, respectively.
M, the image is formed on the intermediate recording medium 6 by using the developing device 8Y to form images for four colors. When these image formations are completed,
The transfer material P such as paper stored in the paper feed unit 9 is transferred to the pickup roller 2 at this timing.
8, the paper is fed by the paper feed roller 29, and the registration rollers 3
0, the sheet is conveyed to the transfer fixing section 間 の between the second heating element 13 and the pressure roller 14 via the sheet feeding guide 31.

The four-color toner image formed on the intermediate recording medium 6 in the transfer fixing section Τ is simultaneously transferred and fixed onto the transfer material P by the heat of the second heating member 13 and the pressure of the pressure roller 14. Then, the sheet is discharged onto the discharge tray 33 through the discharge roller 32, and the full-color image formation is completed.

In FIG. 1, reference numeral 34 denotes a manual paper feed port. The manual paper feed port is used when a transfer material such as thick paper or thin paper which is difficult to feed from the paper feed cassette 9 is used. The transfer material is conveyed by the roller 35 to the transfer fixing section 間 の between the second heating body 13 and the pressure roller 14.

After the completion of the formation of the full-color image in the transfer fixing section Τ, the toner remaining on the surface of the intermediate recording medium 6 is
The cleaning member 15 is cleaned by bringing the cleaning member 15 into contact with the intermediate recording medium 6, and is prepared for the next step.

Next, the intermediate recording medium 6 will be described in detail.

As shown in FIG. 5, the intermediate recording medium 6 comprises a conductive substrate 6a and a conductive release layer 6b, and a toner image is formed on the conductive release layer 6b.

As the conductive substrate 6a, aluminum,
Metal sheets such as nickel stainless steel, polyester,
For high heat resistant resins such as PET (polyethylene terephthalate), PFA (tetrafluoroethylene-perfluoroalkylvinyl ether copolymer), PTFE (polytetrafluoroethylene), polyphenylene sulfide, polyamide imide, polyimide, polyether ketone, and liquid crystal polymer , A mixture of conductive substances such as carbon yellow, ITO, tin oxide, copper, silver, and aluminum, or a composite material of these conductive substances and ceramics, glass, or the like.

As the conductive release layer 6b, for example, PV
Fluorine resin such as DF, PET, PTFE, or a thin layer of fluorine rubber, silicone resin, silicone rubber, or the like provided on the surface as a release layer can be used, and the conductive release layer 6b has at least one layer of toner. As long as it has a capacitance larger than the minute, it can be included as a device that substantially obtains the effect of the present invention. Further, as more preferable conductive release layer 6b, a fluororesin such as PVDF, PET and PTFE, a fluororubber, a silicone resin and a silicone rubber, the above-mentioned carbon yellow, ITO, tin oxide, copper,
A mixture of conductive materials such as silver and aluminum can be used.

The volume resistance of the intermediate recording medium 6 is different from that of the developing devices 8C, 8M, and 8Y during image formation.
The electric field between them is preferably 10 ⁷ Ωcm or less in order not to be affected by the charge of the toner image at the preceding stage. The intermediate recording medium 6 has a particularly excellent releasability by providing the conductive release layer 6b on the conductive substrate 6a. Therefore, the transfer efficiency to the transfer material P at the time of simultaneous transfer and fixing of the toner image is 100%. %.

When the release layer 6b is provided with conductivity as described in the above preferred embodiment, a heat-resistant base that does not provide conductivity can be used as the base 6b. Even with this configuration, the surface layer is the same as described above, exhibits a sufficiently low resistance, and has excellent releasability, so that the same effects as described above can be obtained.

The structure of the intermediate recording medium 6 is not limited to the above-described one. For example, as shown in FIG. 6, a conductive substrate 6a and a conductive release layer 6b may be formed on a heat-resistant substrate 6c.

As the heat resistant substrate 6c, polyester,
High heat resistant resins such as PET (polyethylene terephthalate), PFA (tetrafluoroethylene-perfluoroalkylvinyl ether copolymer), PTFE (polytetrafluoroethylene), polyphenylene sulfide, polyamide imide, polyimide, polyether ketone, liquid crystal polymer, etc. Flexible sheet can be used.

With this configuration, it is possible to easily prevent leakage from the back surface of the intermediate recording medium 6.

In the above-described embodiment, the endless intermediate recording medium 6 is used as a recording medium.
For example, it is also possible to use a recording medium having a configuration in which a long film with a roller wound end is run at a predetermined speed from a feeding shaft to a winding shaft via a heating element.

Next, the first heating element 1 as a heating means is used.
The 2a, 12b, 12c, 12d and the second heating element 13 will be described in detail with reference to FIG. Note that the configurations of the heating elements 12a, 12b, 12c, and 12d are the same,
Hereinafter, the first heating element 12a will be described.

The first heating elements 12a, 12b, 12c, 1
2d is a fixing member fixedly supported by an immovable member (not shown). The inner surface of the intermediate recording medium 6 is rotated by a driving system (not shown) of the driving roller
While sliding on the heating surfaces a, 12b, 12c, and 12d, they move clockwise (in the direction of arrow a) at a predetermined transport speed (50 mm / sec in the present embodiment).

The first heating element 12a is a low heat capacity linear heating element whose longitudinal direction is perpendicular to the rotational movement direction of the intermediate recording medium 6 (transfer belt width direction).

The first heating element 12a includes a heater substrate 40a, an energizing heating element layer 40b formed at a substantially central portion of the upper surface of the heater substrate 40a along the longitudinal direction thereof in the form of a narrow band or a line. A heat-resistant glass 40c, which is a surface protection layer covering the upper surface of the heater substrate 40a including the energized heating element layer 40b with a thickness of about 10 μm, a temperature detecting element 40d provided on the lower surface of the heater substrate 40a, and an insulating support for the heater substrate 40a. And a heater support 40e.

The heater substrate 40a is a member having heat resistance, insulation, and low heat capacity. For example, the heater substrate 40a has a thickness of 1 mm and a width of 5 mm.
An alumina substrate having a length of 10 mm and a length of 310 mm can be used.

The heating element layer 40b is a coating layer made of an electric resistance material such as Ag / Pd (silver palladium) or Ta ₂ N and formed by screen printing with a thickness of 10 μm and a width of 1 to 3 mm.

The temperature detecting element 40 d is, for example, a heater substrate 40.
a low-heat-capacity resistance thermometer such as a Pt film applied to the lower surface of the heater substrate 40a by screen printing or the like, or a low-heat-capacity adhesive which is bonded to a substantially central portion of the lower surface of the heater substrate 40a by a silicone-based adhesive having good heat conductivity. NTC thermistor and the like.

The heater support 40e is connected to the heater substrate 4
0a, a heat-generating layer 40b, a heat-resistant glass 40c, and a heat-insulating layer for supporting the heat-generating layer 40b. The layer has heat insulating properties, high heat resistance, and rigidity. Etc., or a composite material of these resins and ceramics, metal, glass or the like.

The first heating elements 12a, 12b, 12c, 1
2d is configured as described above, and when electricity is supplied to the heating element layer 40b, heat is generated and the temperature of the heater substrate 40a rises. Then, the temperature of the heated heater substrate 40a is measured by the temperature detecting element 40d.
The temperature of the heating element layer 40b is fed back to a control device (not shown) to control the power supply to the heating element layer 40b, thereby controlling the heating element layer 40b to a predetermined assumed arrival temperature (120 ° C.).

The first heating elements 12a, 12b, 12c, 1
The temperature control of 2d is performed for each of the developing devices 8K, 8C, 8M,
In 8Y, the temperature is controlled to be a predetermined temperature immediately before the image formation, and the power supply is stopped immediately after the image formation is completed to prevent the intermediate recording medium 6 and its surroundings from rising in temperature.

Here, the power supply to the heating element layer 40b is performed, for example, by applying a pulse corresponding to a desired temperature and energy release amount controlled by the temperature detecting element 40d with a pulse-like waveform having a cycle of 20 ms of DC100V. Give and change. For example, the pulse width is 0.5 to 5 ms. Also,
At AC100V, by controlling the phase angle to be energized by an energization control circuit (not shown) including a triac according to the detected temperature of the heater substrate 40a of the temperature detecting element 40d,
Control the power supply.

As described above, the first heating elements 12a and 12a
b, 12c, 12d are the heater substrate 40a, the heating element layer 4
0b, the heat capacity of the heat-resistant glass 40c, and the heat capacity of the temperature measuring element 40d are small and are insulated by the support body 40e.
The temperature of the heater substrate 40a reaches the assumed temperature at which the toner layer on the intermediate recording medium 6 can be attached in a short time. Therefore, there is no need to perform standby temperature control in which the first heating elements 12a, 12b, 12c, and 12d are energized and heated in advance, and energy can be saved, and the temperature rise in the intermediate recording medium 6 and its surroundings can be prevented. .

Next, the second heating member 13 for transferring and fixing the toner image formed on the intermediate recording medium 6 at the same time as the transfer will be described. The second heating element 13 is also used as the first heating element 12.
Since the configuration is the same as the configuration a, the description thereof is omitted. Here, the relationship between the timing of the energization control and the pressure roller 14 and the transfer material P will be described.

The control temperature of the second heating element 13 is 180 ° C.
And The temperature of the second heating member 13 is controlled so that the transfer material P reaches a predetermined temperature immediately before passing through the simultaneous transfer fixing unit T, and immediately after the transfer, the power is stopped to prevent the intermediate recording medium 6 and the surroundings from rising in temperature. I do. The method of energizing the second heating element 13 is the same as that of the first heating element 12a, 12b, 12c, 12d, and reaches a desired temperature in a short time, so that there is no need for standby temperature control and energy saving is realized. In addition to this, it is possible to prevent the temperature in the intermediate recording medium 6 and the peripheral device from rising.

The pressure roller 14 is formed by forming a highly releasable skin layer such as PFA or PTFE on a heat-resistant rubber elastic body such as silicone rubber. The intermediate recording medium 6 is brought into contact with and separated from the intermediate recording medium 6 in such a manner as to pinch it.

The timing of the contact / separation is as follows: after the four color toner images are formed on the intermediate recording medium 6, immediately before passing through the simultaneous transfer fixing section T or when the transfer material P is fed by the feed roller 29 and the registration roller 30 Immediately before the sheet is conveyed to the simultaneous transfer fixing section T via the sheet feeding guide 31, for example, 2 to 20 k
gf, preferably 4 to 8 kgf, with the intermediate recording medium 6 being pressed against the upper surface of the second heating member 13 in such a manner as to pinch the intermediate recording medium 6. At a speed, the intermediate recording medium 6 rotates in a forward direction with respect to the rotational movement direction.

As described above, by simultaneously transferring and fixing the toner image assumed on the intermediate recording medium 6 onto the transfer material P, a good image can be stably obtained.

As the developer used in the present embodiment, a polymerized toner can be preferably used. The polymerized toner can be formed as a uniform spherical toner having a small particle size, and can form an image with good image quality.
On the other hand, the polymerized toner is generally considered to have a weaker adhesion to the intermediate recording medium than the ordinary pulverized toner, but even in such a case, in the present embodiment, the conductive transfer Since an image is formed on a material and assumed, the toner can be firmly fixed, which is very effective.

<Second Embodiment> In the first embodiment,
Although the first heating elements 12a, 12b, 12c, and 12d are each provided with a temperature detecting element 40d to perform temperature control independently, in the present embodiment, as shown in FIG. In this configuration, the temperature detecting element 40d is provided only in the heating element 12a. Other configurations are the same as those in the first embodiment, and a description thereof will be omitted in the present embodiment.

In this embodiment, the temperature of the first heating element 12a is controlled by measuring the temperature of the temperature detecting element 40d, and the other first heating elements 12b, 12c, 1c are linked with this temperature control.
By performing the 2d temperature control, in addition to the effects obtained in the first embodiment, the temperature can be simplified and the cost can be reduced.

In this embodiment, the developing device 8K,
Since 8C, 8M, and 8Y are arranged close to each other and subjected to multiple development on one intermediate recording medium 6, a short time is required from the start to the end of image formation.
Even when the temperature control of a, 12b, 12c, and 12d is performed in conjunction with each other, it is possible to prevent the temperature of the intermediate recording medium 6 and its surroundings from rising in the apparatus.

<Embodiment 3> In Embodiment 1 described above,
Control electrode 2 provided in each of developing devices 8K, 8C, 8M, 8Y
Although a large number of openings 20a of 3b are independent circular shapes, in the present embodiment, as shown in FIG.
3b is formed in one slit shape along the longitudinal direction of the developing sleeve 21 (the direction orthogonal to the moving direction of the intermediate recording medium 6), and the slit-shaped opening 2a is formed.
In this configuration, a plurality of control electrodes 23b divided in a quadrangular shape are arranged side by side on both sides of Oa. Other configurations and the structure of the control electrode 23b are the same as those in the first embodiment, and a description thereof will be omitted in the present embodiment.

The control electrodes 23b opposed to each other with the opening 20a interposed therebetween are controlled independently, so that the opening 20
The toner 7K (toners 7C, 7M, 7Y) carried on the developing sleeve 21 is caused to fly through the fine opening areas 20b divided between the control electrodes 23b opposed to each other with the toner image a on the intermediate recording medium 6. Can be formed (transferred). Note that the control method of each control electrode 23b is the same as that in the first embodiment, and therefore is omitted in the present embodiment.

As described above, also in the present embodiment, similar to the first embodiment, there is no scattering of the toner image, and a good image can be formed stably.

In each of the above embodiments, a full-color image forming apparatus including a four-color developing system has been described. However, it is needless to say that the present invention can be applied to a single-color or plural-color image forming apparatus.

<Embodiment 4> FIG. 10 is a schematic configuration diagram showing an image forming apparatus (a printer which outputs two-color images of red and black in this embodiment) according to the present embodiment. Note that members having the same functions as those in the above embodiment are denoted by the same reference numerals, and redundant description will be omitted.

As shown in the figure, a developing device 8K for developing a black (black) toner 7K and a red developing device 8K are provided below an intermediate recording medium 6 which is a recording medium which is rotationally driven in the direction of arrow a (clockwise). A developing device 8R for developing the (red) toner 7R is provided, and a planar first heating element 12 is disposed inside the intermediate recording medium 6 facing the developing devices 8K and 8R. The configuration of the developing devices 8K and 8R is the same as that of each developing device of the first embodiment, and a description thereof will be omitted in the present embodiment.

The intermediate recording medium 6 is suspended around a driving roller 10, a driven roller 11, and a drum-shaped second heating element 13, and the driving roller 10 and the driven roller 11 are provided at both ends with bearing members. (Not shown), the bearing is rotatably supported by the bearing.

Next, an image forming operation by the image forming apparatus of the present embodiment will be described.

First, the developing device 8 corresponding to the input image signal
K and 8R sequentially form black and red toner images on the intermediate recording medium 6, respectively. The intermediate recording medium 6 includes the driving roller 1
With the drive rotation of 0, the inner surface of the intermediate recording medium 6 slides on the heating surface of the first heating element 12 and moves in the clockwise direction (the direction of the arrow a) in the clockwise direction (the direction of arrow a).
(m / sec).

Intermediate recording medium 6 by developing devices 8K and 8R
The formation (transfer) of the toner image on the upper side can be performed in the same manner as in the first embodiment. Then, the toner image is tentatively deposited on the intermediate recording medium 6 by the heating of the first heating body 12. The temperature of the first heating element 12 is controlled by each developing device 8K,
In 8R, the temperature is controlled so as to reach a predetermined temperature immediately before image formation, and immediately after the image formation is completed, the power supply is stopped to prevent the temperature of the intermediate recording medium 6 and its surroundings from rising.

When the image formation is completed, the transfer material P stored in the paper feeding unit 9 is fed by the pickup roller 28 and the paper feeding roller 29 in synchronization with the timing, and the registration roller 30 Via the guide 31, the sheet is conveyed to the transfer fixing section T where the second heating element 13 and the pressure roller 14 are in contact with each other via the intermediate recording medium 6.

The two-color toner image formed on the intermediate recording medium 6 in the transfer fixing section T is simultaneously transferred and fixed on the transfer material P by the heat of the second heating member 13 and the pressurization by the pressure roller 14. Then, the sheet is discharged onto the discharge tray 33 through the discharge roller 32, and the two-color image formation is completed.

After the completion of the two-color image formation in the transfer and fixing section T, the toner remaining on the surface of the intermediate recording medium 6 is
The cleaning member 15 is cleaned by bringing the cleaning member 15 into contact with the intermediate recording medium 6, and is prepared for the next step.

Next, the second heating element 13 and the pressure roller 14 for transferring and fixing the toner image formed on the intermediate recording medium 6 at the same time will be described.

The second heating element 13 is a known fixing roller, and is used to press the transfer material P with the pressure roller 14 to fix the transfer material P using heat and pressure.

The second heating element 13 is driven to rotate by driving means (not shown), and the pressure roller 14 is driven to rotate accordingly. In the second heating body 13 and the pressure roller 14,
As shown in FIG. 11, heaters 13 for heating are respectively provided.
a and 14b are built in. A thermistor (not shown) for detecting the surface temperature of the pressure roller 14 is provided on the outer peripheral surface of the pressure roller 14, and the heater 1 based on the surface temperature information of the pressure roller 14 detected by the thermistor.
The power supply to 3a and 14b is controlled. This heater 13a,
The surface temperature of the second heating element 13 and the pressure roller 14 is maintained at a predetermined value (for example, 180 ° C.) suitable for fixing an unfixed toner image on the transfer material P by controlling the power supply to the transfer member 14b. It is.

As described above, also in the present embodiment, similar to the first embodiment, there is no scattering of the toner image, and a good image can be stably formed.

In each of the above-described embodiments, an example in which the thermal attachment is performed as the thermal attachment means has been described. However, the temporary attachment may be performed using adhesive force. In this case, the assumed adhesion means that when the toner image formed on the intermediate recording medium is not heated when transferred, it has an adhesive property such that only 20% or less is transferred, and when heated, the transfer rate is 90%. It has a sticky surface which can be as described above.

It is also possible to adjust the surface by applying a pressure-sensitive adhesive on the conductive layer of the sheet as a recording medium by a known means as described in JP-A-9-104849. It is.

As a developer (toner) used in each of the above-described embodiments, a microcapsule toner 50 containing an adhesive substance 50a as shown in FIG. 12 can be used.

The microcapsule toner 50 is configured such that a shell 50b on the surface is covered with an adhesive substance 50a and a coloring material 50c. This microcapsule toner 50
Can be easily prepared by a known microcapsule preparation technique such as a chemical method, a physicochemical method, or a mechanical physical method.

As the pressure-sensitive adhesive substance 50a, it is sufficient to use a known pressure-sensitive adhesive, specifically, natural rubber, synthetic rubber, acrylic copolymer, or the like. Can be used as

When the microcapsule toner 50 flies from the developing device of each of the above-described embodiments onto the intermediate recording medium 6 to form a toner image, the impact of the microcapsule toner 50 colliding with the intermediate recording medium 6 is caused. The adhesive substance 50a in which the shell 50b on the surface is broken and contained
As a result, the coloring material 50c is fixed on the intermediate recording medium.

Therefore, by using the microcapsule toner 50 containing the above-mentioned adhesive substance 50a,
Since the provisional application of the toner image can be performed without using the above-described first heating element, the configuration of the apparatus can be simplified, and the cost can be reduced.

When a re-peelable pressure-sensitive adhesive as described in JP-A-5-9449 is used, the pressure-sensitive adhesive remains on the surface of the intermediate recording medium when it is simultaneously transferred and fixed onto a recording medium. And can be easily transferred.

Further, in each of the above-described embodiments, the example in which the toner is carried on the rotating sleeve and conveyed as the supply means for supplying the fine particles to the opening, but the toner is placed on the fixed plate. It is possible to carry an electric field or to carry an ultra-short wave, and to supply toner to the opening in a cascade by gravity.

In each of the embodiments described above, the example in which the recording medium is moved with respect to the fixed opening is described. However, the image may be formed by moving the opening with respect to the fixed recording medium. It is possible. Such a configuration is also included in the present invention.

[0112]

According to the above-described image forming apparatus of the present invention, since the recording medium is formed of a conductive member, the electric field during image formation is substantially affected by the electric charge of the fine particles on the recording medium. And a good image can be stably formed.

Further, by immediately assuming the fine particle image formed by flying the charged fine particles from the fine particle carrier onto the recording medium, disturbance of the fine particle image is prevented, the scattering of the image is prevented, and a stable image is obtained. And a good image can be formed, and furthermore, contamination of the apparatus and the environment can be prevented.

[Brief description of the drawings]

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

FIG. 2 is a diagram for explaining an image forming method of the image forming apparatus according to the first embodiment of the present invention.

FIG. 3 is a plan view showing an aperture electrode of the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 4 is a diagram illustrating an example of a method for forming an aperture electrode.

FIG. 5 is a sectional view showing an intermediate recording medium of the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 6 is a sectional view showing another example of the intermediate recording medium of the image forming apparatus according to Embodiment 1 of the present invention.

FIG. 7 is a schematic configuration diagram illustrating a main part of the image forming apparatus according to the first embodiment of the present invention.

FIG. 8 is a schematic configuration diagram illustrating a main part of an image forming apparatus according to a second embodiment of the present invention.

FIG. 9 is a plan view showing control electrodes of the image forming apparatus according to Embodiment 3 of the present invention.

FIG. 10 is a schematic configuration diagram showing an image forming apparatus according to Embodiment 4 of the present invention.

FIG. 11 is a schematic configuration diagram showing a main part of an image forming apparatus according to Embodiment 4 of the present invention.

FIG. 12 is a cross-sectional view illustrating an example of a toner used in the image forming apparatus according to each of the embodiments of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Apparatus main body 2 Image reading device 5 Image reading unit 6 Intermediate recording medium (recording medium) 6a Conductive base 6b Conductive release layer 6c Heat resistant base 7K Black toner (fine particles) 7C Cyan toner (fine particles) 7M Magenta toner (fine particles 7Y Yellow toner (fine particles) 7R Red toner (fine particles) 8K, 8C, 8M, 8Y, 8R Developing device 9 Paper feed cassette 10 Drive roller 11 Follower roller 12, 12a, 12b, 12c, 12d First heating element (assumed) Attachment means) 13 Second heating element 14 Pressure roller 15 Cleaning member 20 Developing container 20a Opening 20b Micro-opening area 21 Developing sleeve (fine particle carrier) 23 Aperture electrode 23a Insulating substrate 23b Control electrode 23c Insulating layer 27 Toner layer regulation Blade 40a Heater substrate 40b through Electric heating element layer 40c Heat resistant glass 40d Temperature sensor 40e Heater support 50 Microcapsule toner (fine particles) 50a Adhesive substance 50b Shell 50c Colorant

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tadashi Furuya 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (reference) 2C162 AE25 AE31 AE40 AE74 AE87 CA03 CA13 CA24 2H029 DB00 DB04 DB05 DB06 DB13

Claims (10)

[Claims] An opening, a control electrode disposed around the opening, fine particles, charging means for charging the fine particles, and supply means for supplying the fine particles to the opening. Controlling the charged fine particles supplied by the supply means electrostatically by applying a voltage to the control electrode, thereby selectively passing and flying through the opening to form a fine particle image on a recording medium. An image forming apparatus for forming the recording medium, the recording medium being formed of a conductive member, and having a hypothetical attachment means for hypothetically attaching the fine particle image formed on the recording medium by flying from the opening to the recording medium. An image forming apparatus, characterized in that: 2. A rotatable fine particle carrier for supporting charged fine particles on its surface, a relatively moving recording medium disposed to face the fine particle carrier at a predetermined distance, and the fine particle carrier and the recording medium. A plurality of openings formed between the medium and a medium, and electrodes provided around each of the openings, and the charged fine particles supplied by the supply unit are applied to the control electrode by applying a voltage to the control electrode. An image forming apparatus, wherein the fine particle image is formed on the recording medium by selectively passing and flying through the opening by electrostatically controlling, and then the fine particle image is transferred to a transfer material. Is formed by a conductive member, and by applying a voltage to the recording medium using the recording medium as a counter electrode, the charged fine particles fly from above the fine particle carrier and the fine particles formed on the recording medium. Has a temporary fixing means for temporarily fixing an image on the recording medium, the image forming apparatus characterized by. 3. The image forming apparatus according to claim 1, wherein the fine particle image assumed on the recording medium is heated and pressed to be transferred to a transfer material and fixed. 4. The image forming apparatus according to claim 1, wherein the hypothetical attachment section hypothetically attaches the fine particle image by applying heat to the recording medium. 5. The image forming apparatus according to claim 1, wherein the hypothetical attaching unit hypothetically attaches the fine particle image onto the recording medium by an adhesive force. 6. The image forming apparatus according to claim 1, wherein the opening is formed in a circular shape. 7. The opening has a slit shape formed in a direction orthogonal to the moving direction of the recording medium, and the electrodes divided so as to face both sides of the slit-shaped opening are provided side by side. The image forming apparatus according to claim 1, wherein: 8. The image forming apparatus according to claim 1, wherein the recording medium has a conductive release layer formed on a conductive substrate. 9. A method in which a plurality of the fine particle carriers are arranged along the moving direction of the recording medium, and the fine particles of an arbitrary color carried on the respective fine particle carriers are sequentially flown onto the recording medium to produce color fine particles. The image forming apparatus according to claim 1, 2, 3, 4, 5, 6, 7, or 8, which forms an image. 10. An electronic device comprising: an opening; a control electrode disposed around the opening; fine particles; charging means for charging the fine particles; and supply means for supplying the fine particles to the opening. Controlling the charged fine particles supplied by the supply means electrostatically by applying a voltage to the control electrode to selectively pass and fly through the opening, thereby forming a fine particle image on a recording medium. In the image forming apparatus, the fine particles are microcapsule toners containing an adhesive part material, and the image formed by the microcapsule toners formed by flying from the openings is formed on the recording medium by the adhesive. After attaching by the adhesive force of the part material,
An image forming apparatus, wherein the image is transferred and fixed on a transfer material at the same time.