JPH02272586A - Wet type electrophotographic transfer device - Google Patents

Abstract

PURPOSE:To perform the stable transfer by a simple mechanism by using a soft material for at least either of an image carrier and a transfer material and providing a pressing means which is formed of a soft material and presses the transfer material and/or image carrier made of the soft material from its reverse surface side against the other when a toner image is transferred. CONSTITUTION:At least either of the image carrier 44 and transfer material is made of the soft material and the pressing means 94 which is made of the soft material and presses the transfer material and/or image carrier 44 from its reverse surface side against the other when the toner image is transferred is provided. Then the toner image formed on the image carrier 44 with the liquid developer 54 which contains at least toner particles and carrier liquid is dried by a drying means 40 and then transferred to a transfer material by an electrostatic transfer means 46. At this time, the pressing means 94 formed of the soft material presses the transfer material and/or image carrier 44 made of the soft material from the reverse surface side against the other. Consequently, the stable transfer is performed by the simple mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wet electrophotographic transfer device that transfers a toner image formed using a liquid developer to a transfer material.

[Prior Art] A wet electrophotographic transfer device is known that develops an electrostatic latent image on a photoreceptor with a liquid developer and transfers the developed image to a transfer material such as transfer paper.

According to the above transfer device, the device that develops the electrostatic latent image on the photoconductor with a liquid developer and then transfers the image while providing a predetermined gap between the photoconductor and the transfer material is an example of a dry electrophotographic device. In the case of a wet type electrophotographic apparatus, it was proposed in Japanese Patent Application Laid-Open No. 61-500188, and in the case of a wet electrophotographic apparatus, in Japanese Patent Application Laid-Open No. 60-159755.

Furthermore, Japanese Patent Application Laid-open No. 118788/1983 proposes an apparatus in which a developed photoreceptor and a transfer material are pressed by a roller or the like to bring them into close contact for transfer.

Furthermore, a device has also been proposed in which at least one of the transfer material and the photoreceptor is brought into close contact with each other as a soft body.

[Problems to be Solved by the Invention] However, the devices proposed in JP-A-61-500188 and JP-A-60-159755 require a carrier liquid to sufficiently fill the gap. If it is present between the photoreceptor and the transfer material, flow will occur in the carrier liquid during transfer, causing flow in the transferred image, lowering the resolution after transfer, and making it impossible to perform stable transfer. Furthermore, since it is necessary to maintain a constant gap, the mechanism becomes complicated and impractical.

In addition, in the device proposed in JP-A No. 61-118788, the carrier liquid on the photoreceptor flows during close contact, causing the image on the photoreceptor to be distorted and the toner image to be crushed, resulting in lower resolution and transfer efficiency. However, it is not possible to transfer stably.

Furthermore, in devices that bring the transfer material and at least one of the photoreceptors into close contact as a soft body, air bubbles and dust are likely to get mixed in between the transfer material and the photoreceptor, resulting in transfer defects and making it difficult to perform high-resolution transfer. However, stable transfer was not possible.

The present invention has been made in consideration of the above facts, and an object of the present invention is to provide a wet electrophotographic transfer device that uses a liquid developer and is capable of performing stable transfer with a simple mechanism.

[Means for Solving the Problems] A wet electrophotographic transfer device according to the present invention includes at least one of the image carrier and the transfer material made of a soft material, and the transfer material and/or the image made of the soft material at the time of transferring a toner image. The structure is characterized in that a pressing means made of a soft material is provided for pressing the carrier from the back side to the other side.

[Function] In the present invention having the above configuration, the toner image formed on the image carrier by the electrophotographic liquid developer containing at least toner particles and carrier liquid is dried by the drying means and then transferred by the electrostatic transfer means. transferred to the material. At this time, the transfer material and/or the image carrier made of soft material are pressed from the back side to the other side by the pressing means made of soft material.

[Effects of the Invention] According to the present invention configured as described above, in an electrophotographic transfer device using a liquid developer, at least one of the image carrier or the transfer material is made of a soft material, and the pressing means made of the soft material presses the image carrier or the transfer material. Since the image is transferred using a simple mechanism, stable transfer can be performed with a simple mechanism, and it has the excellent effect of being able to perform high-resolution transfer.

[Embodiment] Figures 1 and 2 show a first embodiment of a wet electrophotographic transfer device 10 according to the present invention. Note that FIG. 1 is a perspective view showing the external appearance of the wet electrophotographic apparatus 10, and FIG. 2 is a sectional view showing a transfer section provided inside the apparatus.

The wet type electrophotographic transfer device 10 is provided with a document table 14 on the top surface of a box-shaped device main body 12 and a transfer material insertion portion 16 projecting upward from the top surface. Further, at the lower front of the main body 12 of the apparatus, there is a developer unit (1 day) containing liquid developer.
An insertion port 20 (see FIG. 2) is provided, and an ejection port 22 is provided above the insertion port 20 from which a transfer material to which a document image has been transferred is ejected. An insertion opening 26 into which a photoreceptor unit 24 (see FIG. 2) is inserted is provided on one side of the main body 12 of the apparatus. Also, inside the main body 12 of the apparatus is a document table 14.
A lamp (not shown) is provided to irradiate light onto the upper document. Further, as shown in FIG. 2, a detector 28 for detecting image light from a document is disposed within the main body 12 of the apparatus. This detector 28 is connected to a comparison circuit 30.

The comparison circuit 30 is connected to a driver 32 that controls a semiconductor laser 34. The semiconductor laser 34 emits a laser beam toward a polygon mirror 36 that rotates at high speed. By rotating at high speed, the polygon mirror 36 reflects the laser beam onto the photoreceptor of the photoreceptor unit 24.

Therefore, the image light from the original is detected by the detector 28, and the detected result becomes an electrical signal and is input to the comparator circuit 30 for signal processing. The comparison circuit 30 outputs the digitized image signal to the driver 32. Based on this result, the driver 32 irradiates a laser beam from the semiconductor laser 34 to form an electrostatic latent image on the photoreceptor. This electrostatic latent image is transferred to the transfer material inserted from the transfer material insertion portion 16 after being developed with toner using the developer of the developer unit. The transfer material on which the toner image has been transferred is discharged from the discharge port 22 to the outside of the main body 12 of the apparatus.

As shown in FIG. 2, the transfer section 3 includes a photoreceptor unit 24, a developer unit 18, and a drying device 40.

The photosensitive unit 24 is equipped with a photosensitive drum 42, which is connected to a driving means (not shown) and rotates counterclockwise in FIG. 2.

A photoreceptor 44 is provided on the outer peripheral surface of the photoreceptor drum 42 . The photoreceptor 44 may be a well-known organic photoconductor or an inorganic photoconductor.

It is also possible to use a dielectric material charged with a charging needle.

Organic photoconductors include a wide variety of well-known organic photoconductors. Specifically, “Research Disclosure J
(Re5erch Disclosure) Magazine #10
938 (Article entitled "Electrophotographic Elements, Materials and Processes", May 1973 issue, p. 61 et seq.).

For example, an electrophotographic photoreceptor made of poly-N-vinylcarbazole and 2,4,7-dolinitrofluoren-9-one (U.S. Pat. No. 3,484
．． 237), poly-N-vinylcarbazole sensitized with pyrylium salt dye (Japanese Patent Publication No. 4B-25658)
, an electrophotographic photoreceptor whose main component is an organic pigment (Japanese Unexamined Patent Publication No. 1983
-37543), an electrophotographic photoreceptor whose main component is a eutectic complex consisting of a dye and a resin (Japanese Patent Publication No. 47-10735), an electrophotographic photoreceptor with copper phthalocyanine dispersed in a resin (Japanese Patent Publication No. 52-1667), etc. There is.

Others, Journal of Electrophotography Society, Volume 25, No. 3 (1986
), substances listed in paragraphs 62 to 76 of the above are included.

Further, as the inorganic photoconductor used in the present invention, “Electro Photography J (rt!electro-
photogrphy4 R, M, 5chaffert
Author, Focal Press (London)) (
Various inorganic compounds disclosed in pages 260 to 374 (1975) are representative. Specific examples include zinc oxide, zinc sulfide, cadmium sulfide, selenium, selenium-tellurium alloy, selenium-arsenic alloy, selenium-tellurium-arsenic alloy, and the like.

In addition, amorphous silicon can also be mentioned.

A corona charger 46 is arranged above the position where the laser beam is incident. A power source (not shown) is connected to this corona charger 46.

Therefore, after the surface of the photoreceptor 44 is uniformly charged by the corona charger 46, the photoreceptor drum 42 rotates counterclockwise in FIG. 2, and a laser beam is incident on the surface of the photoreceptor in accordance with the original image. Photoreceptor 4 into which image light is incident
4 becomes conductive and the charge on its surface disappears,
An electrostatic latent image is formed on the surface of the photoreceptor 44.

A developer unit 18 inserted from the insertion opening 20 is located below the position where the laser beam is incident in accordance with the original image.
is placed.

The unit main body 48 of the developer unit 18 is a box with an open top, and a liquid developer bottle 50 and a rinse liquid bottle 52 are housed inside.

A liquid developer 54 is contained in the liquid developer bottle 50, and any known developer can be used as the liquid developer 54. For example, Tokko Kokan Sho 35-551
1 Special Publication No. 35-13424, Special Publication No. 50-40017,
Special Publication No. 49-98634, Special Publication No. 58-129438,
Examples include the developer disclosed in JP-A-61-180248, Fundamentals and Applications of Electrophotographic Technology (Electrophotographic Society Line, Corona Publishing (198B)), and the like.

These liquid developers generally include a carrier liquid, a colorant that forms toner particles, a coating agent made of a polymeric resin that provides fixation properties for the colorant, and a coating agent that promotes the dispersion of toner particles and works to stabilize the dispersion. It consists of a dispersant to control the polarity and charge amount of the toner particles, and a charge control agent to control the polarity and charge amount of the toner particles.

As the coating agent, various known resins can be used, but in particular, JP-A No. 61-180248 and JP-A No. 63-41
272, copolymers of ethylene and (meth)acrylic acid, copolymers of ethylene and vinyl acetate, copolymers of ethylene and ethyl acrylate, and ethylene and (meth)acrylic acid esters disclosed in JP-A No. 63-41273. Ethylene-based copolymers such as copolymers of ethylene, (meth)acrylic acid, and (meth)acrylic acid ester copolymers can be preferably used.

The electrical resistance of the carrier liquid and rinsing liquid is 1 x 109Ω.
- A non-polar non-aqueous solvent with a dielectric constant of 1 or more and 3 or less can be used. Examples of the non-aqueous solvent include solvents such as linear or branched aliphatic hydrocarbons, aliphatic hydrocarbons, aromatic hydrocarbons, and halogenated hydrocarbons, but there are concerns regarding volatility, safety, odor, etc. From the point of view, octane, isooctane, decane, isodecane, dodecane, isododecane, nonane, isoparaffin-based petroleum solvents Isopar E1 Isopar G1 Isopar H1 Isopar L (Isoper rIsoper is a trade name of Exxon Corporation), Tsurupez 100, Shell Silua 1 ( (manufactured by Shell) etc. are suitable.

The toner particle concentration in the developer is not particularly limited, but is 0.1 to Log per 12 developer. (In other words, the carrier liquid is 100 to 10,000 g per toner particle.) Various known charge control agents can be used, and the concentration thereof is 0.01 to Log, preferably 0.01 per 12 developer particles. ~1g. Further, various known dispersants can be used, and the concentration thereof is preferably 0.01 to 50 g per developer 12, preferably 0.1 to 10 g.

One end of a conduit 56 is inserted into the liquid developer 54 in the developer bottle 50 . The other end of this conduit 56 is communicated with a developer supply body 58 . A developer supply pump 60 is disposed in the middle of the pipe line 56 . Also, a filter 6 is placed around the tip of the pipe 56 inserted into the developer solution.
2 are arranged. Further, the developer supply body 58 has a conduit 6.
One end of the developer bottle 4 is communicated with the developer bottle 50, and the other end thereof is opened into the developer bottle 50. The developer supply body 58 is disposed close to the photoconductor 44, and a plurality of developer discharge ports are formed on the surface facing the photoconductor 44. Therefore, when the developer supply pump 60 operates, the liquid developer 54 is filtered through the filter 62 and then sent through the pipe 56 to the developer supply body 58 from the developer discharge port to the surface of the photoreceptor 44. The developer 54 is discharged to. Excess developer is removed from pipe 64.
The developer is collected into the developer bottle 50 by the following steps.

One end of a pipe line 68 is inserted into the rinse liquid 66 in the rinse liquid bottle 52. The other end of this pipe line 68 is in communication with a rinsing liquid supply body 70 . A rinsing liquid supply pump 72 is disposed in the middle of the pipe line 68. Also, around the tip of the pipe 72 that is inserted into the rinsing liquid 66,
A filter 74 is provided. In addition, the rinsing liquid supply body 7
One end of the pipe line 76 is communicated with the rinsing liquid bottle 52, and the other end thereof is opened into the rinse liquid bottle 52. Rinse liquid supply body 70
is arranged close to the photoconductor 44, and a plurality of rinse liquid discharge ports are formed on the surface facing the photoconductor. Therefore, by the operation of the rinsing liquid supply pump 72, the rinsing liquid 66 passes through the filter 74 and is filtered.
8 to a rinse liquid supply body 70, and excess rinse liquid is collected into the rinse liquid bottle 52 by a conduit 76.

Further, one end of a pipe line 78 is communicated with the inside of the rinse liquid bottle 52. The other end of the conduit 78 extends above the photosensitive drum 42 and opens toward a space between a transfer material and a photosensitive member 44, which will be described later.

A squeeze roller 80 is disposed on the downstream side of the rinsing liquid supply body 70 in the rotational direction of the photosensitive drum 42 so as to be in contact with the surface of the photosensitive member 44 . This squeeze roller 80
The rinsing liquid supplied to the surface is squeezed out from the surface. In this squeeze, the thickness of the rinse liquid 66 is set to be 100 μm or less, preferably 50 μm or less.

A drying device 40 is disposed on the side of the developer unit 18. One end of an air duct 84 communicates with the air pump 82 of the drying device 40, the middle part of the air duct 84 rises along the surface of the photoreceptor 44, and the other end opens upward.

Further, an opening 84A opening toward the photoreceptor 44 is provided in the intermediate portion facing the photoreceptor 44. Therefore, dry air supplied from the air pump 82 is blown onto the surface of the photoreceptor 44 through the opening 84A. The air flow rate is lf/min or more per unit area, preferably 1 lf/min or more per unit area.
01/win or more, preferably 1001/mi
It is set to n or more. The air blowing time is 1 sec or more, preferably 10 sec or more, and more preferably 30 sec or more.
sec or more.

Further, one end of an air duct 86 is communicated with the air pump 82 . The other end of the air duct 86 branches into two parts above the corona charger 46 , one of which is open toward the photoreceptor 44 . The other side extends upward and opens toward the back side of a guide plate 108, which will be described later.

A charger 88 is located above the air duct 86, and a charger 88 is connected to the photoreceptor 44.
is placed towards the surface. This charger 88 applies a voltage of opposite polarity to the toner to the dried photoreceptor 44 .

Two rollers 90 and 92 are disposed above the photosensitive drum 42 and between the corona charger 46 and the charger 8 along the outer periphery of the photosensitive member 44 . An endless belt 94 is wound between these rollers 90 and 92. A portion of this endless belt 94 located on the photoreceptor 44 side is in contact with the photoreceptor 44, and the transfer material is inserted between the endless belt 94 and the photoreceptor 44.

The endless belt 94 is made of a soft material such as rubber or felt, and presses the transfer material onto the surface of the photoreceptor 44. This pressing force is 0.1kg/c4~2.0kg/cj
preferably 0.5kg/cd to 1
．． 5kg/d is good.

The mata rollers 90 and 92 are soft rollers made of rubber or sponge, and have a soft surface.

A pair of conveyance rollers 96 is arranged above the rollers 90 . Further, a pair of guides 98 are provided above the conveyor roller pair 96.
is located. The conveyance roller pair 96 is pivotally supported between a pair of side plates (not shown), is rotated by the transmission of the driving force of a driving means (not shown), and the transfer material guided by the guide 98 is inserted and nipped and conveyed.

The transfer material to be inserted is the one described above, and is made of a soft material. In this case, the photoreceptor 44 may be made of a soft material, as long as at least one of the transfer material or the photoreceptor 44 is made of a soft material.

A conveying roller pair 100 is arranged on the side of the roller 92. Further, a peeling claw 101 is arranged between the conveying roller pair 100 and the roller 92. This peeling claw 101 peels off the transfer material from the surface of the photoreceptor 44 and removes the transfer material from the conveying roller pair 10.
Insert between 0.

Furthermore, on the side of the conveying roller pair 100, a roller 102.
104 are arranged. These rollers 102.10
An endless belt 106 is wound between the four. A guide plate 10 is disposed at the bottom of the endless belt 106, and is in contact with half the circumference of the endless belt 106, and between the guide plate 108 and the endless belt 106, the guide plate 106 is placed between the guide plate 108 and the endless belt 106. Transfer material is inserted. The guide plate 108 is attached to the opening of the air duct 86. Therefore, the transfer material is dried by air supplied from the drying device 40 through the air duct 86.

Note that the transfer material used in this embodiment is not particularly limited, and various materials can be used.

For example, plain paper, various surface coated papers, ZnO coated paper,
Examples include aluminum substrates for printing plates, plastic films such as polyethylene terephthalate, polyethylene, and triacetyl cellulose, and films coated with various film metals or coated with various polymers.

All of the aluminum substrates used in general presensitizing plates (23rd edition) can be used as printing aluminum substrates, but the surface has to be treated with graining treatment called graining, anodizing treatment, etc. An aluminum substrate is preferred.

Next, the operation of the first embodiment will be explained.

The wet electrophotographic transfer device 10 is powered on.

Next, the developer recording the image to be transferred is placed on the document table 14, and the transfer material is inserted into the apparatus main body 12 from the transfer material insertion section 16.
Insert inside.

When a transfer start switch (not shown) is turned on, the corona charger 46 is activated to charge the photoreceptor 44 uniformly, and at the same time the photoreceptor drum 42 is rotated counterclockwise in FIG. 2 by a driving means (not shown). When the uniformly charged photoreceptor 44 is positioned at the exposure position, a lamp (not shown) irradiates light onto the original on the original 14, and image light from this original is detected by the detector 28. This detection result becomes an electrical signal and is transmitted to the comparison circuit 30. From the comparison circuit 30, the signal of the original image is digitized and transmitted to the driver 32. The comparison circuit 30 operates the semiconductor laser 34 to irradiate a laser beam corresponding to the original image. As a result, the photoreceptor 44 is image-exposed.

When the surface of the photoreceptor 44 is exposed to image light, the portion irradiated with the laser beam becomes conductive and the surface is uncharged (thus, an electrostatic latent image corresponding to the original image is formed).

The photoreceptor 44, on which the electrostatic latent image has been formed, further rotates counterclockwise in FIG. 2 and faces the developer supply member 5.

Developer is supplied to the developer supply body 58 by the operation of a developer supply pump 60, and the developer is discharged toward the surface of the photoreceptor 44 from a developer discharge port (not shown). As a result, toner particles in the developer adhere to the image area or non-image area where the electrostatic latent image is formed, the electrostatic latent image is visualized, and the toner image corresponding to the image area or non-image area is formed. It is formed.

The photoconductor 44, on which toner particles have adhered and a toner image has been formed, is further rotated counterclockwise in FIG.
A rinsing liquid 66 is supplied by a rinsing liquid supply pump 72 and is discharged toward the surface of the photoreceptor 44 from a rinsing liquid discharge port (not shown). With this rinsing liquid 66,
The developer containing unnecessary toner particles adhering to areas of the surface of the photoreceptor 44 other than image areas or non-image areas to which toner should adhere is washed away.

Photoreceptor 44 from which unnecessary substances on the surface have been removed with rinsing liquid 66
is held between the squeeze roller 80 and the photosensitive drum 42, and the rinsing liquid remaining on the surface is squeezed out. On the surface of the photoreceptor 44 in this state, toner is electrostatically adhered to the image area or non-image area of the document image, forming an electrostatic latent image.

In this state, the photoreceptor 44 further rotates counterclockwise in FIG. 2 and faces the opening 84A of the air duct 84. From the opening 84A of the air duct 84, the air pump 8
Dry air supplied from 2 is discharged onto the surface of the photoreceptor 44. This dry air makes the photoreceptor 44 moist.
is dried.

This drying evaporates the carrier liquid (rinsing liquid) existing between the toner particles forming the electrostatic latent image, thereby increasing the interaction (bonding force) between the toner particles. In this drying, 2 On+ rinsing liquid 66 as a carrier liquid per 1 g of toner
g or less, preferably 10+ag or less, more preferably 5 mg or less.

In this way, since squeezing is performed by the squeeze roller 80 before drying by the drying device 40, the amount of air blown during drying is extremely small, the air blowing process is shortened, and the odor caused by the evaporated organic solvent is also reduced. It is also possible to prevent uneven development caused by air blowing.

The photoreceptor 44, which has been dried by the dry air, further rotates counterclockwise in FIG. 2, and a charge having the same polarity as that of the toner is applied by the charger 88.

In this state, it comes into contact with the endless belt 94.

On the other hand, the transfer material inserted into the apparatus main body 12 from the transfer material insertion section 16 is guided between a pair of guides 98, inserted between a pair of transport rollers 96, and sent between the photoreceptor 44 and the endless belt 94.

At this time, the transfer material has an electrostatic latent image formed by toner particles, is superimposed on the photoreceptor 44, and is pressed onto the photoreceptor 44 by the endless belt 94.

Further, a rinsing liquid 66 is supplied between the photoreceptor 44 and the transfer material through a conduit 78 by the operation of a rinsing liquid supply pump 72 . This rinsing liquid can be supplied to either the photoconductor 44 side or the transfer material side, but if the transfer material has high liquid absorption, the supply amount can be smaller if it is supplied to the photoconductor 44 side. .

As described above, in this embodiment, the endless belt 94 is made of a soft material and the endless belt 94 presses the transfer material against the photoreceptor 44, so that stable transfer can be performed with a simple mechanism.

Further, a transfer voltage having a polarity opposite to that of the toner is applied to the transfer material by a power source (not shown). As a result, it adheres to the surface of the photoreceptor 44. The toner particles are attracted to the surface of the transfer material, move through the rinsing liquid, and adhere to the transfer material, forming a transferred image of the toner particles on the transfer material. As a result, an original image is formed on the surface of the transfer material.

Furthermore, since the rinsing liquid 66 is supplied between the transfer material and the photoreceptor 34 during transfer, image disturbances caused by toner particles flowing during transfer are prevented.

The amount of the rinsing liquid 66 supplied varies depending on the material of the transfer material, and for example, when the transfer material does not absorb the rinsing liquid, which is a non-aqueous solvent, such as an aluminum substrate or a polyethylene terephthalate film, it is 2 to 80 g/rrf. is suitable, and 2 to 40 g/bo is more preferable.

When using paper as a transfer material, it is difficult to specify the amount of rinse liquid to be supplied depending on the paper, whether it is plain paper, coated paper, art paper, waterproof paper, or the thickness. Transfer paper, Copy Ace A) is 20~
80 g/rrf is preferred.

The transfer material on which the toner image has been transferred is removed by a peeling claw 101.
As a result, the photoreceptor 44 is peeled off from the surface and inserted between the pair of transport rollers 100. The transfer material sent out from the transport roller pair 100 is inserted between the guide plate 108 and the endless belt 106. Dry air is supplied from the lower part of the guide plate 108 by an air duct 86 and is blown onto the transfer material. As a result, the transfer material moistened with the rinsing liquid 66 is dried. The dried transfer material is discharged from the discharge port 22 to the outside of the apparatus main body 12 and placed on a transfer material tray (not shown).

On the other hand, the photoreceptor 4 after the transfer material is peeled off by the peeling claw 101
4 is again uniformly charged on its surface by the corona charger 46, and then image light from the original to be transferred is incident thereon.

As described above, in this embodiment, since the photoreceptor 44 is dried before transfer, the resolution of the transferred image, which had conventionally been 25 fp/mm, has been improved to 502 p/ll11.

Transfer methods for transferring the toner image on the photoreceptor 44 to the transfer material include electrostatic transfer, corona transfer, bias roller transfer, and if the transfer material is conductive, a transfer method in which a voltage is directly applied. These include, but are not particularly limited to.

Further, in this embodiment, after the toner image on the photoreceptor 44 was substantially dried, it was charged with the opposite polarity to the toner particles, but corona discharge with the same polarity was performed to uniformly charge the image on the photoreceptor 34. A precharging charger may be arranged to charge to the same polarity. This makes it possible to improve the transfer efficiency in the next step.

ll Uraship■ Next, a second embodiment will be described using FIG. 3.

As shown in FIG. 3, two rollers 112 and 114 are arranged above and below in the transfer section 110 of the second embodiment.
A small diameter roller 116 is arranged on the side of the roller 114. The roller 11B is in contact with the small diameter roller 116. Small-diameter roller 116 and roller 11 in contact with it
8 is rotated by the driving force of a driving means (not shown) transmitted thereto. Also, endless belt 1 is attached to rollers 112, 114, 116.
20 is wound around in a substantially triangular shape to form an inclined portion 120A, a vertical portion 120B, and a horizontal portion 120C, and is held between a small diameter roller 116 and a roller 118. Therefore, when the small diameter roller 116 and the roller 118 are rotated by the driving force of a driving means (not shown), the endless belt 120 is rotated clockwise in FIG. A photoreceptor 122 made of a photoconductive layer is provided on the outer surface of the endless belt 120 over the entire circumference.

As this photoconductor, the one shown in the first embodiment is used.

A laser irradiated from above the side of the photoreceptor 120 (in the direction of arrow A in FIG. 3) is incident onto the photoreceptor 122 .

A corona charger 124 is located below the position where the image light is incident.
is located. A power source (not shown) is connected to this corona charger 124, and the surface of the photoreceptor 122 of the endless belt 120 rotating clockwise in FIG. 2 is uniformly charged.

A developer supply port 128 attached to one end of a conduit 126 is arranged above the roller 120. Conduit 1
The other end of 26 is a developer bottle 50 of the developer unit 18.
It is connected to the inside. Further, a developer supply pump 60 is disposed in the middle of the conduit 126, and a filter 62 is disposed around the tip communicating with the inside of the developer bottle 50. The liquid developer 44 contained in the developer bottle 50 is transferred to the filter 62 by the operation of the developer pump 60.
After passing through and being filtered, the developer 44 is supplied onto the photoreceptor 122 from a developer supply port through a conduit 126.

Further, a developer recovery roller 1 is provided at the bottom of the developer supply port 128.
30 is in contact with the surface of the photoreceptor 122. A developer recovery port 132 is provided in the recovery roller 130 . The developer recovery port 132 is attached to one end of a conduit 134, and the other end of the conduit 134 communicates with the inside of the developer bottle 50.

As a result, excess developer 44 on the photoreceptor 122 is squeezed and then passes through the conduit 134 to the developer bottle 50.
It is collected inside.

A rinse liquid supply port 136 is arranged below the recovery roller 130. This rinse liquid supply port 136 is connected to a pipe line 138.
attached to one end of the

The other end of the conduit 138 opens into a rinse liquid bottle 52 housed within the developer unit 18 .

Further, a rinse liquid supply pump 72 is arranged in the middle of the pipe line 138, and a filter 74 is arranged around the end of the pipe line 138 communicating with the inside of the rinse liquid bottle 52. The rinse WL is activated by the operation of the rinse liquid supply pump 72.
66 is filtered by filter 74 and then the conduit 138
The rinsing liquid is supplied to the surface of the photoreceptor 122 from the rinsing liquid supply port 136 through the rinsing liquid supply port 136 .

A squeeze roller 140 is provided at the bottom of the rinse liquid supply port 136.
is arranged in contact with the surface of the photoreceptor 122. This squeeze roller 140 squeezes excess rinsing liquid 66 from the surface of the photoreceptor 122.

One end of an air duct 142 is connected to the air pump 82 of the drying bag 240 on the side of the developer unit. The middle part of the air duct 142 is the squeeze roller 1
The roller 40 is disposed along the surface of the photoreceptor 122 up to the bottom of the roller 40 , and the other end is open on the side of the squeeze roller 140 . A photoreceptor 122 is located in the middle of the air duct 142.
An opening 142A is provided which is open toward. By operating the air pump 82, dry air is blown through the air duct 142 from the opening 142A onto the surface of the photosensitive weight 22.

Further, an air duct 144 is arranged in the air pump 82. The other end of the air duct 144 is bifurcated at the side of the roller 118. - side is endless belt 120
Corona charger 12 is extended along inclined portion 120A of
It is open on the 40 side. An opening 144A that opens toward the photoreceptor 122 is provided in the opposing portion of the inclined portion 120A of the endless bell l-120. The other side extends above the transfer material support plate 146 disposed at the lower part of the horizontal portion 120C of the endless belt 120, and has an opening in the middle toward the transfer material support plate 140, and the tip portion extends upward. It is open towards.

A roller 14 is disposed below the transfer material support plate 146 and supports the lower portion of the transfer material support plate 146. - Also, a pair of conveyance rollers 150 is arranged on the side of the transfer material support plate 146 (on the right side of the paper in FIG. 3). A transfer material is inserted between the pair of transport rollers 150,
The transfer material is conveyed between the horizontal portion of the photoreceptor 122 and the transfer material support plate 146.

The transfer material to be inserted is the same as in the first embodiment, but is made of a soft material as in the first embodiment. In this case, at least one of the photoreceptor and the transfer material may be made of a soft material.

A charger 152 is disposed opposite the roller 114. This charger 152 charges the dried toner image.

Further, one end of a conduit 154 is open on the transfer material support plate 146 . The other end of the pipe line 154 is connected to the rinse liquid bottle 5
It opens into 2. A supply pump 156 is disposed in the middle of the conduit 154.

Therefore, the operation of the supply pump 156 supplies the rinsing liquid 54 onto the transfer material.

Next, the operation of this embodiment will be explained.

A document on which an image to be transferred is recorded is placed on the document table 14, and a transfer material is inserted into the apparatus main body 12 from the transfer material insertion section 16.

When a transfer start switch (not shown) is activated, the corona charger 112 is activated to uniformly charge the surface of the photoreceptor 122, and at the same time, the endless belt 120 is moved counterclockwise in FIG. 3 by a driving means (not shown). When the photoreceptor 122, whose surface is uniformly charged, reaches the exposure position, the document platen 14
The upper original image is scanned, and the laser beam 34 is incident on the photoreceptor 122 via the polygon mirror 36 to expose it.

When the surface of the photoreceptor 122 is exposed to light, the portion of the image area or non-image area on which light is incident becomes conductive, and the charge on the surface disappears, leaving a charge on the image area or non-image area.
Forms an electrostatic latent image.

The photoreceptor 122 with the electrostatic latent image formed on its surface is further conveyed and faces the developer supply port 128 .

The liquid developer 54 supplied by the operation of the developer supply pump 60 is discharged from the developer supply port 128 onto the surface of the photoreceptor 122 . As a result, toner particles in the liquid developer adhere to the electrostatic latent image, the electrostatic latent image is visualized, and a toner image corresponding to an image area or a non-image area is formed.

The photoreceptor 122, on which toner particles have adhered to the surface and a toner image has been formed, is further conveyed counterclockwise, and excess liquid developer remaining on the surface is squeezed out by a developer collection roller 130. The squeezed liquid developer passes from the recovery port 132 through the pipe line 134 to the developer bottle 50.
It is collected inside.

The photoreceptor 122 that has passed the developer recovery roller 130 faces a rinsing liquid supply port 136, and is supplied with a rinsing liquid sent through a conduit 138 to wash away unnecessary substances adhering to the surface. The photoreceptor 122 in this state faces the opening 142A of the air duct 142 after the rinse liquid 66 is squeezed out by the squeeze roller 140. Dry air is supplied to the air duct 142 by the air pump 82, and is blown onto the surface of the photoreceptor 122 from the opening 142A. As a result, the rinsing liquid, which is a carrier liquid existing between the toner particles adhering to the surface of the photoreceptor 122 to form a toner image, is removed and aggregated.
The distance between toner particles becomes shorter. As a result, the interaction (bonding force) between toner particles is increased, toner particles do not spread during transfer, and a toner image with high resolution is formed.

The photoreceptor 122 on which a toner image is formed by agglomeration of toner particles by dry air is further conveyed to the charger 1.
52.

The photoreceptor 122 whose surface is charged by the charger 152 is conveyed to the horizontal portion 120C facing the transfer material support plate 146.

On the other hand, the transfer material is inserted into the apparatus main body 12 from the transfer material insertion section 16, conveyed along a conveyance path (not shown), and inserted between the pair of conveyance rollers 150, and then inserted between the transfer material support plate 146 and the horizontal portion 1000 of the photoreceptor 122. inserted between. A toady image formed on the photoreceptor 122 is transferred to the transfer material conveyed between the photoreceptor 122 and the transfer material support plate 146. During this transfer, the rinsing liquid 6 is
6 is supplied between the photoreceptor 122 and the transfer material.

The outer periphery of the roller 114 is made of a soft material, and presses the photoreceptor 122 against the transfer material via the endless belt 120. This embodiment is suitable for a relatively rigid transfer material, and the photoreceptor 122 is made of a soft material.

Therefore, the image is transferred to the photoreceptor 122 by being pressed from the back side by a roller 114 made of a soft material.

Therefore, stable transfer can be performed with a simple mechanism, and high-resolution transfer can be performed.

The transfer material onto which the toner image of the photoreceptor 122 has been transferred is conveyed to the left side in the drawing, and is dried by being blown with dry air sent by the air duct 144 from the opening.

Dry air sent by the air duct 144 is also blown onto the photoreceptor 122 being conveyed from the horizontal portion 120C to the inclined portion 120A, and after being dried, the photoreceptor 122 is transferred to the corona charger 1 again.
24, and image light from a document to be transferred next is incident thereon.

In this way, in the second embodiment, the transfer material is placed on the transfer material support plate 14 which is arranged horizontally with the horizontal portion 120C of the photoreceptor 122.
Since the toner image is transferred while being pinched and conveyed between the transfer material 6 and the toner image, it is relatively rigid and suitable for transferring a toner image onto a thick transfer material.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a first embodiment of a wet electrophotographic transfer device according to the present invention, FIG. 2 is a schematic side view showing a transfer section of the first embodiment, and FIG. 3 is a transfer section of a second embodiment. FIG. 10...Wet type electrophotographic transfer device, 40/44. 90. 94, drying device, 122... photoreceptor, 92.114... roller, 120... endless belt.

Claims (1)

[Claims] (1) In a wet electrophotographic transfer device in which a toner image formed on an image carrier by an electrophotographic liquid developer containing at least toner particles and a carrier liquid is dried by a drying device and then transferred to a transfer material by an electrostatic transfer device. , at least one of the image carrier and the transfer material is made of a soft material, and is formed of a soft material that presses the transfer material and/or the image carrier from the back surface side to the other when transferring the toner image. A wet type electrophotographic transfer device characterized by being provided with a pressing means.