JPH03120557A - Image forming device for developing by wet process - Google Patents

Abstract

PURPOSE:To prevent foul smell and to improve image fixing characteristics by dispersing toner contg. agents into a carrier liquid contg. >=50vol.% 1st component contg. <= 5monomer silicone oil having a cyclic siloxane structure and a 2nd component contg. an aliphat. hydrocarbon of a petroleum system as a developing soln. CONSTITUTION:Electrostatic latent images are formed on a charge carrying member 21 via electrostatic latent image forming means 22, 10 and the development of these images by a wet process is executed by a means 60 for development by the wet process. The developing soln. used in this case is pred. by dispersing the toner contg. The coloring agents into the carrier liquid contg. >=50 vol.% 1st component contg. <=5 monomer silicone oil having the cyclic siloxane structure and the 2nd component consisting of the aliphat. hydrocarbon of the petroleum system. The foul smell generated by the aliphat. hydrocarbon of the petroleum system are drastically decreased in such a manner and the flocculation of the toner in a developing unit and cleaning unit by the evaporation of the carrier liquid is lessened, by which the deterioration in the quality of recorded images is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wet development image forming apparatus, and in particular, an electrostatic latent image is developed with a developer. The present invention relates to a wet development type image forming apparatus.

[Prior Art] A developing solution for this type of image forming apparatus is disclosed in, for example, Japanese Patent Application Laid-Open No.
No. 17419, JP-A-61-180248.

Japanese Unexamined Patent Application Publication No. 63-4249 is conventionally known.

Generally, in wet-type copying machines, in order to obtain good image fixing properties, it has been conventionally used as a developer.

A toner containing a colorant and a resin as main components dispersed in a carrier liquid made of a petroleum-based aliphatic hydrocarbon solvent is used. That is, typical reprinted petroleum-based aliphatic hydrocarbon solvents include Isopar C, E, G, H, and K manufactured by Esso Standard Co., Ltd. under the name Isopar.

L and M are known.

The film properties include high electrical resistance (XIO'' Ω1 or more) and low dielectric constant (
ε = 3 or less), low dissolving power, transparent with almost no odor, non-irritating to the skin and harmless, low flammability (50°C or higher) and thermal stability.
For example, it dries quickly.

Table 1 also shows the relationship between boiling point and average molecular weight for each isoper.

A liquid developer is made by kneading a colorant, a dispersion resin, and a small amount of other additives with the carrier liquid using a ball chemir, kedimir, or other means to form a concentrated toner, and then dispersing this in an appropriate amount of the carrier liquid. I can do it.

However, today, wet copying machines also use PPC (Plain
As paper copying has progressed, even higher image density is required, and the demand for higher image density has been met by depositing a large amount of toner on transfer paper.

However, increasing the amount of toner adhering reduces the fixing performance, so in order to improve the fixing performance, either increase the temperature of the fixing roller of the fixing device or use a solvent with good evaporation performance (for example, Isopar H9G or E or a mixture) has been adopted.

[Problem to be solved by the invention]

However, increasing the temperature of the heater of the fixing roller of the fixing device increases power consumption, which limits the power capacity that can be used by the user, resulting in a problem that limits the attachment of a wide variety of peripheral devices to the copying machine.

On the other hand, if a solvent with good evaporation performance is used, the area around the copying machine will be filled with solvent gas when a large number of copies are made, giving the user an unpleasant odor. In the solution alone.

Although the odor is not very strong, the solvent gas that evaporates during fixing becomes a strong odor when a large amount of copies are made.

Therefore, since the organic solvent is used in a room without ventilation, it is undesirable from a sanitary standpoint, causing problems such as limitations on copying speed.

Furthermore, since solvents with good evaporation properties dry quickly, untransferred toner and accumulated toner in the developing unit and cleaning unit turn into sludge, and if drying progresses over a long period of time, flakes that are difficult to redisperse can be formed. Large particles (which do not contribute to development) are generated. This large particle has a size (1
~500μ) is the toner particle size (0.5~0.8μ)
), it gets stuck in the gap (100 to 150 microns) between the developing roller and the photoreceptor, causing abnormal images such as white streaks and black spots.

SUMMARY OF THE INVENTION An object of the present invention is to provide a wet development image forming apparatus that generates less foreign odor and less deteriorates the quality of recorded images.

[Means to solve the problem]

(1) A charge carrier (21), a latent image forming means (22, 10) for forming an electrostatic latent image corresponding to a recorded image on the charge carrier (21), and.

static@, wet developing means (60) for developing the latent image with a developer;
In the wet development image forming apparatus, the developer includes a silicone oil having a cyclic siloxane structure.
The toner is characterized in that a toner containing a colorant is dispersed in a carrier liquid containing 50% by volume or more of a first component consisting of a substance having a molecular weight or less, and a second component consisting of a petroleum-based aliphatic hydrocarbon. Wet-type image forming device.

(2) a charge carrier (21), a latent image forming means (22, 10) for forming an electrostatic latent image corresponding to a recorded image on the charge carrier;
A wet developing image forming apparatus including a wet developing means (60) for developing an electrostatic latent image with a developer.

The developer is a carrier liquid containing 50% by volume or more of a first component made of a silicone oil having a cyclic siloxane structure with a viscosity of 4.0 cs or less and a second component made of a petroleum-based aliphatic hydrocarbon. A wet developing image forming device characterized by dispersing toner containing a toner.

(3) a charge carrier (21), a latent image forming means (22, 10) for forming an electrostatic latent image corresponding to a recorded image on the charge carrier;
In a wet developing image forming apparatus comprising a wet developing means (60) for developing an electrostatic latent image with a developer, the developer is a first silicone oil having a boiling point of 210° C. or lower and having a cyclic siloxane structure. It is characterized in that a toner containing a colorant is dispersed in a carrier liquid containing 50% by volume or more of the above components and a second component consisting of a petroleum-based aliphatic hydrocarbon. Wet-type image forming device.

Note that symbols in parentheses indicate corresponding elements in an embodiment shown in one drawing and described later.

[Function] (1) Silicone oil having a cyclic siloxane structure of pentamer or less is virtually odorless, and since it is contained in the carrier liquid at 50% by volume or more, the odor generated by petroleum-based aliphatic hydrocarbons is eliminated. significantly reduced.

In addition, silicone oil having a cyclic siloxane structure of 5'ffi or less has a boiling point higher than that of petroleum aliphatic hydrocarbons, so it is difficult to evaporate, and toner agglomerates in the developing unit and cleaning unit due to evaporation of the carrier liquid. There are few
Abnormal images such as white streaks and black spots are less likely to occur, and the quality of recorded images is less likely to deteriorate. When the boiling point is high, it is difficult for the carrier liquid to evaporate during fixing, which lowers the fixing properties. However, since the carrier liquid contains a second component with good fixing properties, this maintains good fixing properties, and the fixing properties are also at an acceptable level. It falls within the following range.

(2) Silicone oil having a cyclic siloxane structure with a viscosity of 4.0 or less is virtually odorless, and is added to the carrier liquid for 50 minutes.
Since it contains 0% by volume or more, the odor generated by petroleum-based aliphatic hydrocarbons is significantly reduced.

In addition, silicone oil having a cyclic siloxane structure with a viscosity of 4.0 or less has a higher boiling point than petroleum-based aliphatic hydrocarbons, so it is difficult to evaporate, and there is less aggregation of toner in the developing unit and cleaning unit due to evaporation of the carrier liquid. , abnormal images such as white streaks and black spots are less likely to occur, and deterioration in recorded image quality is reduced. When the boiling point is high, it is difficult for the carrier liquid to evaporate during fixing, which lowers the fixing properties.However, since the carrier liquid contains a second component with good fixing properties, this maintains good fixing properties, and the fixing properties are also within an acceptable level. fits in.

(3) Silicone oil with a cyclic siloxane structure with a boiling point of 210°C or lower is virtually odorless, and the carrier liquid contains 50% or more by volume of it, which significantly reduces the odor generated by petroleum-based aliphatic hydrocarbons. do. Also, the boiling point is 21
Silicone oil with a cyclic siloxane structure at 0°C or below has a higher boiling point than petroleum-based aliphatic hydrocarbons, so it is difficult to evaporate, and toner aggregation in the developing unit and cleaning unit due to evaporation of the carrier liquid is less likely, resulting in less white streaks and Abnormal images such as black spots are less likely to occur, and the quality of recorded images is less likely to deteriorate. If the boiling point is high, it is difficult for the carrier liquid to evaporate during fixing, which lowers the fixing properties, but since the carrier liquid contains a second component with good fixing properties, this maintains good fixing properties and keeps the fixing properties within an acceptable level. It fits.

(Embodiment) FIG. 1 shows a wet development copying machine which is an embodiment of the present invention. The original is placed on the contact glass plate 12 with the pressure plate 11 opened.
placed on top. Directly below the contact glass plate 12,
An optical scanning system 10 is provided, and an image forming unit 20 is provided below it. The lower side of the original on the contact glass plate 12, that is, the image to be copied,
It is illuminated by an exposure lamp 13 of an optical scanning system 10.

The reflected light from the original is reflected by the first mirror 14. Second mirror 15
．． Third mirror 16. The light passes through the lens unit 17 and the fourth mirror 18 and is imaged on the surface of the photosensitive drum 21 provided in the image forming unit 20 .

In the optical scanning system 10, an exposure lamp 13 and a first mirror 14 are mounted on a first carriage (not shown), and a second mirror 15 and a third mirror 16 are mounted on a second carriage. The first carriage and the second carriage are each scanned and driven at a constant speed in the direction of arrow A in FIG. 1. The speed of the second carriage is 172 times the speed of the first carriage. Therefore, as the first and second carriages move, the original images on the contact glass plate 12 are sequentially scanned, and the read images are formed on the photoreceptor drum 21.

On the other hand, in the image forming unit 20, the photosensitive drum 21 is rotated at a constant speed in the direction of the arrow in the figure. After the surface of the photoreceptor drum 21 is charged to a negative potential by the main charger 22, the surface of the photoreceptor drum 21 is charged to the optical scanning system lO.
Since the surface is exposed to image light, a potential distribution corresponding to the read image, that is, an electrostatic latent image, is formed on that surface.

This electrostatic latent image is visualized with a developer when it passes through a developing unit 60 located in the direction of travel of the photoreceptor drum. That is, toner of the developer is attracted to the surface of the photoreceptor drum 21 according to the potential distribution, and a toner image is formed depending on the high/low potential.

The paper feeding mechanism 30 feeds - sheets of transfer paper (recording paper) to the photoreceptor drum 21 at a predetermined timing synchronized with the formation of the toner image.
This transfer paper, which is fed onto the surface of the photoreceptor drum 21, overlaps the toner image on the photoreceptor drum 21 and moves as the photoreceptor drum 21 rotates, and when it passes through the transfer charger 25, the toner image on the photoreceptor drum 21 is transferred to a transfer paper (transfer), and the transferred paper is transferred to the photoreceptor drum 21 by the separation unit 26.
is peeled off from the fixing unit 5 and transported along a predetermined path to the fixing unit 5.
It reaches 0. The fixing unit 50 fixes the image on the transfer paper to the transfer paper by applying pressure and heating.

The transfer paper that has been fixed is ejected to a paper ejection tray through a paper ejection roller.

In the image forming unit 20, the surface of the photosensitive drum 21 after separation of the transfer paper is as follows.

It is cleaned by a cleaning unit 70.

That is, toner, paper powder, etc. remaining on the surface of the photoreceptor drum 21 are removed.

The developing unit 60 and the cleaning unit 70 include
Each of the mechanisms 40 to which the developer is supplied from the developer supply mechanism 40 is equipped with a tank 41 filled with developer. The liquid is supplied to the developing unit 60 and cleaning unit 70 via 47 . A developer container 42 containing a concentrated developer and a container 43 containing a diluted solution are attached to the tank 41. When the liquid level in the tank 41 drops below a predetermined level due to consumption of the developer, the diluent in the diluent container 43 is automatically drained from the container 43 to the tank 4.
Flows to 1. Further, when the toner concentration in the developer in the tank 41 becomes low, the solenoid device 44 is energized. When the solenoid device 44 is energized, the developer container 42
The mouth of the tank 41 is opened and the concentrated developer is supplied to the tank 41.

Details of the image forming unit 20 and the developer supply mechanism 40 are shown in FIG. l image roller 62. Second developing roller 63 and squeeze roller 6
5 is rotatably supported.

These rollers are electrically conductive and are located a very small distance from the surface of the photoreceptor drum 21. 1st. The second developing rollers 62 and 63 are rotated counterclockwise, and the squeeze roller 65 is rotated clockwise. These rollers are
It rotates when the photoreceptor drum 21 is rotating, and stops when the photoreceptor drum 21 stops.

The developer in the tank of the developer supply mechanism 40 is supplied by a pump 45.
It passes through the supply pipe 47a and is injected into the developing unit from a supply port 61 provided above the developing unit 60. 1st. The second developing roller 62, 63 and the squeeze roller 65 have scrapers 64a, 64b and 6 scrapers, respectively.
The free ends of 4c are in contact. Scraper 64a, 64
b and 64c scrape off the developing solution adhering to the surface of each roller, and also keep the developing solution flowing down from above thereon. 1. The developer remaining on each scraper wets the surface of the roller. The developer on the surface of the second developing rollers 62 and 63 is attracted to the charge on the surface of the photoreceptor drum 21 and transferred to the photoreceptor drum 21.

The squeeze roller 65 removes excess liquid from the surface of the photoreceptor drum 21. The developer remaining in the lower part of the developing unit 60 is drained from the discharge port 66 by its own weight to the recovery pipe 48a.
The developer is collected in the tank 41 of the developer supply mechanism 40.

In the cleaning unit 70 , the surface of a sponge-like foaming roller 73 and one end of a blade 76 are in contact with the surface of the photoreceptor drum 21 .
A squeezing roller 74 arranged to scrape off the remaining developer on the surface of the first foaming roller 73 and to press the first foaming roller 73 squeezes out the developer that has leaked into the first foaming roller 73 .

Furthermore, a developer for cleaning is supplied to the cleaning unit 70 from the developer supply mechanism 40 via a supply pipe 47b. This developer is supplied from the supply lower 1 above the cleaning unit, discharged from the discharge lower 5 below, and passes through the recovery pipe 48b to the tank 41.
Return to

That is, the developer remaining in the unit 70 without being actually used circulates between the tank 41 and the developing unit 60 and between the tank 41 and the cleaning unit 70 and is reused.

In addition, in FIG. 2, 24 is an eraser, and 27 is a static elimination lamp.

Incidentally, a portion of the developer circulated in the developer supply mechanism 40 passes through the inside of the toner concentration detection unit 46 . The toner concentration detection unit 46 includes a light emitting element 46a and a light receiving element 46 facing each other with a slight gap (approximately 0.5 to 1.0 ms) as shown in FIGS. 4a and 4b.
b, and the developer FLD is configured to pass through the gap. In other words, the toner detection unit 4
Reference numeral 6 constitutes a transmission type optical sensor, which generates a signal at a level corresponding to the amount of light transmitted through the TIL image solution, that is, the toner concentration.

The toner concentration detection signal of the concentration detection unit 46 is as follows.

A concentration control unit 80 is provided with the concentration control unit 80 . The density control unit 80 refers to the toner density signal at predetermined time intervals,
When it indicates a concentration lower than the predetermined concentration, the solenoid is connected for a predetermined period of time. ! 44, open the mouth of the lt developer container 42 and drain the concentrated developer inside the tank 41.
Supply a fixed amount to By this control, the toner concentration of the developer in the tank 41 is maintained within a predetermined range while the developer container 42 contains the concentrated developer.

FIG. 3 shows a specific configuration of the fixing unit 50 shown in FIG. 1. Referring to FIG. 3, a fixing roller 51 and a pressure roller 53 are provided along the passage path of the transfer paper 39. . A heater 52 is built into the center of the fixing roller 51 . The pressure roller 53 receives an upward force from the force of the pressure spring 55 and the pressure cam 54, and presses the transfer paper 39 and the toner image 39a attached to its upper surface against the fixing roller 51.

By the way, the developer used in this type of wet copying machine is
It is constructed by dispersing a colorant, a resin, etc. in a carrier liquid, and a petroleum-based aliphatic hydrocarbon solvent such as Isopar H manufactured by Esso Standard Co., Ltd. is used as the carrier liquid.

This type of carrier liquid has excellent fixing properties, so high quality images can be recorded by using it.

However, this type of carrier liquid has the property of being relatively easily evaporated, so when the developer is circulated and reused as in this embodiment, untransferred toner in the cleaning unit 70 and The scraper 64a adheres to the developing rollers 62, 63, and 65.

Most of the toner scraped off by 64b and 64c is returned to the original developer and uniformly dispersed, but the remaining part of the toner becomes sludge and accumulates inside the unit. The sludge-like toner is normally washed away by the circulating liquid flow and collected in the developing tank 41, but after a long period of time, the sludge-like toner leaves the dead spaces (areas where the liquid flow is weak) inside the unit. ) If the copying operation is stopped for a long time, the sludge-like toner gradually dries during that time, producing large flake-like particles that are difficult to redisperse. 63.65 and the photoreceptor drum 21, resulting in image omissions such as white lines and abnormal images such as black spots.

Further, when moving the copying machine, it is necessary to drain the developer inside the copying machine in advance to prevent the developer from spilling outside. However, after moving the copying machine, developer tank 4
If the toner detection unit 46 is left as it is without adding a developer, the light emitting element 46a of the toner detection unit 46 will emit light, as shown in FIG.
The developer FLD remaining in the gap between the light-receiving element 46b and the
dries and adheres to the detection surface of the toner detection unit 46 as dirt. This stain is not easily removed even when a developer is injected, and the level of light received by the toner detection unit 46 is significantly reduced. As a result, toner detection unit 4
If the detected density of No. 6 becomes significantly higher than normal and density control is continued based on the incorrectly detected density, the developer density will abnormally drop and the recording density will drop.

Furthermore, offset is likely to occur during the fixing process.

That is, a portion of the toner image transferred onto the transfer paper may be reversely transferred to the fixing roller 51 or the pressure roller 53, causing a decrease in density or omissions in the recorded image, or the toner adhering to the roller may be transferred to the transfer paper again. There may be cases where In order to prevent this type of offset, - For boat fishing, silicone rubber is used as the material for the roller surface of the fixing device, which is less likely to cause offset, and the roller surface is further coated with silicone oil at all times. There is. However, silicone rubber has relatively low heat resistance and durability, so parts must be replaced periodically depending on the degree of deterioration.6 Also, since it is necessary to apply silicone oil, the fuser It is inevitable that the structure of

In order to avoid the above-mentioned disadvantages, in this example, silicone oil having a siloxane structure and Isopar H (petroleum-based aliphatic hydrocarbon) are used as the carrier liquid of the developer.
A mixture of these is used.

In other words, since silicone oil having a siloxane structure has lower evaporability than petroleum-based aliphatic hydrocarbons, its inclusion makes it difficult for the developer to dry and prevents the toner from becoming flaky particles. This also prevents toner stains from adhering to the toner detection unit 46. Furthermore, since it contains petroleum-based aliphatic hydrocarbon, deterioration in image fixing performance can be prevented. Furthermore, since silicone oil having a siloxane structure itself prevents offset from occurring during the fixing process, materials other than silicone rubber can be used for the fixing roller 51 and pressure roller 53, and silicone oil can also be applied. Can be omitted. In this embodiment, the surfaces of the fixing roller 51, pressure roller 53, and pressure cam 54 (internally made of aluminum) are covered with Teflon (registered trademark: trade name of DuPont), which has high heat resistance and durability. Further, a mechanism for applying thin cone oil is omitted in the fixing unit 50.

In the present invention, from the results of the experiments shown below, among silicone oils having a siloxane structure, in particular silicone oils having a cyclic siloxane structure have a boiling point of 2.
10℃ or less, viscosity 4.0cs or less, or molecular weight 5
A carrier liquid was used in which the volume of the carrier liquid was less than 50% by volume and the proportion of the carrier liquid was 50% by volume or more.

In this experiment, silicone oils having several types of cyclic siloxane structures with different boiling points, viscosities, and molecular weights were mixed with petroleum-based aliphatic hydrocarbons (Isopar [■: manufactured by Esso Standard Co., Ltd.] at a ratio of 100:0, 50:50°, 20:80°). The image density, odor, and fixing properties of the carrier liquids mixed at the ratio of .

The wet-type copying machine used to obtain the data shown in Table 2 was a Lycium type CT-5085.
00W, and the fixing roller surface temperature was 180±10°C.

The transfer paper used was Lycium type 6200, and A-4 size paper with a 7% chart area was continuously passed through. The developing solution was prepared by dispersing a heat-curable toner (disclosed in Japanese Unexamined Patent Publication No. 63-303382) in each carrier liquid at a rate of 100 g per 1Q.

l5oparE, l5opar, which is a silicone oil with
G*l5oparll, l5oparK, l5
oparL and IsoparM are products (trade names) of Esso Standard.

Several types of silicone oils were selected after considering image density, odor, and fixing energy, focusing on those with particularly good evaporation properties, low boiling point, low viscosity, and low molecular weight. Note that it seems possible to fix even high-boiling-point materials by increasing the amount of heat supplied, such as by increasing the temperature of the fixing roller 51 to 180° C. or higher, but this may result in lower durability of the fixing roller, increased power consumption, and safety. There are problems such as decreased sexuality.

The image density is a value measured with a Macbeth densitometer (reflection densitometer).

The numbers 1 to 5 in the odor column indicate the odor after 15 minutes of continuous paper feeding. This shows the degree (rank) of odor in a sensory test conducted in an unventilated room, and the level of odorlessness is 5. 4. Slightly recognizable level. 3. How clearly you feel it. The degree to which it feels slightly strong is expressed by 2 degrees, and the degree to which it feels to be strong is expressed by 1.

Further, the symbol on the fixing sieve indicates the degree (rank) of smear when rubbing the image immediately after paper ejection, and the symbol 0 indicates when there is no image blurring (smear). A case where there is slight image blurring but at an acceptable level is represented by the symbol Δ, and a time when the image blurring is significant is represented by the symbol x.

Regarding odor from Table 2, the comparison of experiment numbers 1 and 2°3 (the same applies to the comparison of experiment numbers 4 and 5.6, and the comparison of experiment numbers 7.8.9).

It can be seen that by mixing 50% by volume or more of silicone oil having a cyclic siloxane structure, it becomes almost odorless.

In addition, regarding fixing properties, a comparison of experiment numbers 1 and 4.7 (
The same applies to the comparison of Experiment Nos. 2 and 5.8 and the comparison of Experiment No. 3゜6.9), the boiling point is 210°C or less and the viscosity is 4.
It can be seen that if the molecular weight is 0 cs or less or the molecular weight is pentamer or less, it becomes almost equivalent to isopar and reaches an acceptable level. Furthermore, regarding the quality of one image, it can be seen that a quality comparable to that of the conventional method can be obtained, which is a particular problem.

As described above, silicone oils having a cyclic siloxane structure that have a boiling point of 210°C or less, a viscosity of 4.0cs or less, or a molecular weight of 50% or less are mixed into the carrier liquid in an amount of at least 50% by volume to eliminate odor. , it is possible to obtain excellent fixing properties.

〔Effect of the invention〕

As described above, according to the present invention, since the first component with low evaporation properties is present, there is little odor generation, and even when the developer in the device is removed and left for a long time, the residual toner is difficult to dry. It does not accumulate on the developing unit or cleaning unit, or adhere to the toner density detection unit and contaminate the detection surface. Therefore, an abnormal image is not caused, and an abnormality in recording density is not caused.

Since the second component provides excellent image fixing properties,
There is no particular deterioration in fixing characteristics.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a cross section of a mechanical part of an embodiment of the present invention. FIG. 2 is an enlarged sectional view showing the structure of the developing unit 60 shown in FIG. 1. FIG. FIG. 3 is an enlarged sectional view showing the structure of the fixing unit 50 shown in FIG. 1. FIG. 4a shows the toner concentration detection unit 46 shown in FIG.
FIG. FIG. 4b is an enlarged front view of a portion of the toner concentration detection unit shown in FIG. 4a. 10: Optical scanning system 20: Image forming unit 21: Photosensitive drum (charge carrier) 22: Main charger (22, 10: latent image forming means)
25: Transfer charger 30: Paper feeding mechanism 40:
Developer supply mechanism 41: Tank 42: Developer container 43: Diluent container 44: Solenoid device i 45: Pump 46: Toner concentration detection unit 50: Fixing unit 60: Developing unit (wet type developing means)

Claims (3)

[Claims] (1) In a wet development image forming apparatus comprising a charge carrier, a latent image forming means for forming an electrostatic latent image corresponding to a recorded image on the charge carrier, and a wet developing means for developing the electrostatic latent image with a developer. , the developer contains 50% by volume of a first component consisting of a pentamer or less of silicone oil having a cyclic siloxane structure.
A wet developing image forming apparatus characterized in that a toner containing a colorant is dispersed in a carrier liquid containing the above and a second component made of a petroleum-based aliphatic hydrocarbon. (2) In a wet development image forming apparatus comprising a charge carrier, a latent image forming means for forming an electrostatic latent image corresponding to a recorded image on the charge carrier, and a wet developing means for developing the electrostatic latent image with a developer. , the developing solution is a carrier liquid containing at least 50% by volume of a first component consisting of a silicone oil having a cyclic siloxane structure with a viscosity of 4.0 cs or less and a second component consisting of a petroleum-based aliphatic hydrocarbon. A wet developing image forming device characterized by dispersing toner containing a colorant. (3) In a wet development image forming apparatus comprising a charge carrier, a latent image forming means for forming an electrostatic latent image corresponding to a recorded image on the charge carrier, and a wet developing means for developing the electrostatic latent image with a developer. , the developer contains 50% of a first component consisting of a silicone oil having a cyclic siloxane structure with a boiling point of 210°C or lower.
1. A wet development image forming apparatus, characterized in that a toner containing a colorant is dispersed in a carrier liquid containing at least % by volume and a second component consisting of a petroleum-based aliphatic hydrocarbon.