JPH0782269B2 - Development device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a developing device for developing a photosensitive material, and more specifically, a developing solution in the form of droplets is supplied to the surface of the photosensitive material to form the photosensitive material. The present invention relates to a developing device for developing.

[Prior Art] A photosensitive material image-exposed is supplied with a developing solution on its surface,
The developing electrode disposed in the developing section controls the amount of the developing solution applied to the surface to perform the developing process.

As a method of supplying the developing solution to the developing section, a method of immersing the photosensitive material in the developing solution or continuously supplying the developing solution to the surface of the photosensitive material is performed.

However, in the above method, an extra developing solution is supplied to the photosensitive material in addition to the developing solution necessary for developing the photosensitive material. For this reason, the developer is wasted.

In order to solve this, a so-called liquid spraying method in which the developer is made into a droplet shape and sprayed onto the surface of the photosensitive material can be considered.

[Problems to be Solved by the Invention] However, in the liquid spraying method of spraying the developing solution onto the surface of the photosensitive material, since the developing solution is diffused from the nozzles from which the developing solution is ejected and sprayed onto the surface of the photosensitive material, The supply amount of the developing solution is different between the central portion of the photosensitive material and its periphery, so that the developing solution is not uniformly supplied to the surface of the photosensitive material, and the photosensitive material cannot be uniformly developed.

Therefore, it is possible to spray a developing solution onto the surface of the photosensitive material with a plurality of nozzles facing the developing area of the photosensitive material, but it is difficult to dispose a plurality of nozzles facing the surface of the photosensitive material. In addition, in a device for developing processing by disposing a developing electrode for adjusting the amount of developer adhered on the surface of the photosensitive material, it is more difficult to dispose a plurality of nozzles on the surface of the photosensitive material.

Further, it is very difficult to arrange a plurality of nozzles so as to face the surface of an electrophotographic image having a small developing area such as a microfilm because the developing electrode is arranged so as to face the developing area of the photosensitive material.

Moreover, since the developing electrode must be connected to the power supply,
A wiring space for this is required, and it is difficult to dispose the nozzles facing the plurality of nozzle photosensitive materials.

In view of the above facts, an object of the present invention is to provide a developing device capable of uniformly supplying a developing solution to the surface of a photosensitive material without waste and reducing the size of a developing electrode.

[Means for Solving the Problems] In the present invention, in a developing device for developing an electrostatic latent image formed on the surface of a photosensitive material, a porous developing electrode having a plurality of small holes corresponding to the developing area of the photosensitive material. A pressurizing chamber provided on the side of the porous developing electrode opposite to the photosensitive material; a supply means for supplying the developer into the pressurizing chamber; and periodically pressurizing the developer in the pressurizing chamber through small holes. And a pressurizing unit for ejecting the developing solution in a droplet state onto the developing area.

[Operation] In the present invention having the above-described configuration, the developing solution is supplied into the pressurizing chamber by the supply unit. The developing solution supplied into the pressure chamber is periodically pressurized by the pressure means. By this pressurization, the developing solution is ejected in a droplet state from the small holes formed in the porous plate toward the developing area of the photosensitive material. As a result, the developing solution is supplied to the developing area of the photosensitive material, and the photosensitive material is developed.

The porous plate also serves as a developing electrode, and the developing electrode adjusts the amount of the developing solution attached to the surface of the photosensitive material. This allows good development to be performed.

Further, since the porous plate also serves as the developing electrode, the developing device becomes compact.

Further, since the developing electrode can be downsized, the piping for supplying the developing solution into the pressurizing chamber can be simplified, and the entire apparatus can be downsized.

Further, since the developing solution is supplied to the developing area of the photosensitive material in a droplet state, it is possible to supply the developing solution to the developing area of the photosensitive material with a small amount of the developing solution.

[Embodiment] FIGS. 1 to 3 show an embodiment of a process head 10 which is an example of a developing device incorporated in an electrophotographic apparatus.
FIG. 1 shows the developing section 16 of the process head 10 and the developing section 16
And FIG. 3 is a perspective view showing the developing section 16, showing the relationship between the developing device 16 and other devices, and taken along the line I--I in FIG.

As shown in FIG. 2, the process head 10 is composed of a relatively flat body portion 12 having a substantially rectangular parallelepiped shape and a pair of leg portions 13 located below the body portion 12 which are integrally formed. ,
Except for attachments, it is integrally molded with synthetic resin.

As shown in FIG. 2, the main body 12 of the process head 10 has a charging and exposing section 14, a developing section 16, and a drying section, which are sequentially arranged in the width direction.
The fixing portion 20 and the fixing portion 20 are formed by a constant pitch corresponding to the distance between one frame of the electrophotographic film 22.

In the charging / exposure unit 14, the electrophotographic film 22 (corresponding to one frame) located at this portion is charged and then exposed by being irradiated with image light from a document not shown. As a result, an electrostatic latent image corresponding to the image pattern of the original is formed on the electrophotographic film 22.

In the developing unit 16, the liquid developing solution is applied to the electrophotographic film 22 exposed by the charging and exposing unit 14 to visualize the electrostatic latent image.

In the drying section 18, dry air is blown to the electrophotographic film 22 moistened with the liquid developer to remove moisture.

In the fixing section 20, the electrophotographic film is fixed by a fixing lamp or the like.
The image is fixed on 22.

In the developing section 16, as shown in FIGS. 1 to 3, a recess 28 formed in the front wall 26 of the process head 10 is provided with a depression chamber 28.
The opening 30 is provided on the side of the front wall 26.

The entire opening 32 of the pressurizing chamber 30 is closed by a diaphragm 34. The vibrating plate 34 is formed of a stainless steel plate having a thickness of about 30 to 50 .mu.m, and as shown in FIG. 3, small holes 36 are formed through the front and back sides at equal intervals in the vertical and horizontal directions. . The area where the small holes 36 are formed corresponds to the developing area of the electrophotographic film 22, and is, for example, about 10 × 8 mm. The distance between the small holes 36 is 200 x 300 μm
The entire area is uniformly arranged in a grid pattern at intervals, and 200 to 500 pieces are formed in the area of 10 × 8 mm. Also this small hole 36
May be arranged in a zigzag pattern as shown in FIG. 3 (B). The diameter of this small hole 36 is set to 10 to 100 μm.

The vibrating plate 34 also serves as a developing electrode, and is connected to a power source 35 to apply a bias voltage to the electrophotographic film 22 to adjust the amount of the developing solution attached. This voltage is 50V-300V
It is set to a degree.

Piezo-vibrator 38 is fixed to the upper and lower sides of the back surface of the diaphragm 34, that is, the inner side of the process head 10. This piezo oscillator 38 is connected to an AC power source 37 as shown in FIG. The AC power supply 37 is connected to one terminal of a bias power supply 35 which is a DC power supply, and the other terminal of the bias power supply 35 is connected to the electrophotographic film 22 and grounded. Therefore, even if the piezo oscillator 38 is used as the developing electrode, it is not affected by the bias power source. The piezo oscillator 38 is a so-called piezoelectric element and has a piezoelectric property of generating a strain force that is deformed in the vertical direction as shown by an arrow in FIG. 4 when a voltage is applied. As shown in FIG. 4, the middle part is vibrated so that it oscillates at about 20 kHz to 100 kHz.

As shown in FIG. 1, an air outlet is provided in the upper part of the pressurizing chamber 30.
48 is formed and communicates with a passage 50 that is formed by the internal space of the process head 10. The passage 50 communicates with an air suction port 52 opened on the upper surface of the process head 10.

A developer supply port 54 is formed in the lower part of the pressure chamber 30,
It communicates with a passage 56 that is formed by the internal space of the process head 10. The passage 56 communicates with a developer inlet 58 opened on the lower surface of the process head 10.

As shown in FIG. 1, the air suction port 52 has a valve 60 in the middle.
Through the pipes 62 and 64 via the. The gas-liquid separation device 66 is connected to the air pump 70 through a pipe line 68, and supplies a negative pressure to the gas-liquid separation device 66. The negative pressure causes the developer in the pressurizing chamber 30 to be sucked into the gas-liquid separator 66.

The gas-liquid separator 66 separates the developer containing air, which flows into the separation tank 67 through the pipe 64, into air and the developer, and prevents the developer from mixing into the air pump 70. is doing.

A branch pipe 69 is branched in the middle of the pipe 64 and communicates with a pressure regulating valve (not shown). With this pressure adjusting valve, the negative pressure supplied by the air pump 70 is adjusted, and the suction amount of the developing solution is adjusted.

The developer inlet 58 is connected to the developer bolt 74 by a pipe 72.

As shown in FIGS. 2 and 3, left and right frames 40 and 42 are provided on both sides of the pressurizing chamber 30 in the width direction so as to project forward from the recess 28. The electrophotographic film 22 positioned at the developing unit 16 contacts the left and right frames 40 and 42, and the space surrounded by the diaphragm 34, the left and right frames 40 and 42, and the electrophotographic film 22 serves as a developing chamber 44. The upper part of the developing chamber 44 is open and communicates with the outside.

The left and right frames 40 and 42 are integrally formed with the main body 12 of the process head 10, and a developing solution outlet 46 is formed in the lower part of the developing chamber 44 over the entire width direction of the developing unit. The developer outlet 46 is a passage 47 formed by the internal space of the process head 10.
It is in communication with. The passage 47 communicates with a developer discharge port 76 opened on the lower surface of the process head 10. The developing solution discharge port 76 is connected to the gas-liquid separation device 80 by a pipe line 78. The gas-liquid separation device 80 is connected to an air pump 84 by a pipe line 82, and a negative pressure is supplied to the gas-liquid separation device 80.

Next, the operation of this embodiment will be described.

A charging exposure unit 14, which is disposed adjacent to the process head 10,
To the developing unit 16, the drying unit 18, and the fixing unit 20, the electrophotographic film
Each frame of 22 is sent in the above order and processed, and an image is recorded on the electrophotographic film 22.

In this case, a film moving motor (not shown) is driven,
A predetermined one freely selected from the unrecorded frames is positioned in front of the charging exposure unit 14. This operation of selecting a predetermined frame is performed by designating a predetermined frame with a control keyboard (not shown) that operates an electrophotographic apparatus (not shown) in which the process head 10 is incorporated.

Here, focusing on this one predetermined frame, the case where the predetermined one frame is sent from the charging exposure section 14 to the developing section 16, the drying section 18 and the fixing section 20 to record an image will be described.

A predetermined frame freely selected from the unrecorded frames is positioned at the charging exposure unit 14 and is charged and exposed to form an electrostatic latent image.

One frame on which the electrostatic latent image is formed is moved to the developing section 16 by a film moving motor (not shown).

In the developing unit 16, the air pump 70 is operated, and a negative pressure is supplied into the pressurizing chamber 30 via the gas-liquid separator 66.
As a result, the developer stored in the developer bottle 74 is sucked up into the pressure chamber 30, and the pressure chamber 30 is filled with the developer.

When a predetermined frame of the electrophotographic film 22 moves to the developing unit 16, a voltage is applied to the piezo-vibrator 38 by a voltage applying means (not shown). By applying this voltage, the piezoelectric vibrator 38 is distorted in the vertical direction as shown by the arrow in FIG. 4, and the diaphragm 34 is expanded and contracted in the vertical direction. Due to this expansion and contraction, the diaphragm 34 vibrates in a wavy manner in the middle portion as shown in FIG. Due to this vibration, the developing solution in the pressure chamber 30 becomes droplets from the small hole 36 and is jetted into the developing chamber 44, is supplied in the form of mist into the developing chamber 44, and is applied to the surface of one frame of the electrophotographic film 22. To be done. As a result, the electrostatic latent image formed on the electrophotographic film 22 is visualized by this developer.

Since the developing chamber 44 is formed by the vibrating plate 34, the left and right frames 40 and 42, and the electrophotographic film 22, the developing solution jetted into the developing chamber 44 is prevented from splashing to the outside.

Although the upper part of the developing chamber 44 is open, since it is sucked by the air pump 84 which is an excluding means for excluding the excess developing liquid, the droplet-shaped developing liquid in the developing chamber 44 is discharged from the developing liquid outlet. It is sucked out from 46 and sent to the gas-liquid separation device 80. As a result, the developer does not scatter from the upper part of the developing chamber 44 to the outside of the developing chamber 44.

Here, the principle that the developer in the pressurizing chamber 30 is ejected as droplets from the small holes 36 due to the liquid vibration of the vibrating plate 34 will be described.

As shown in FIG. 4, the vibration plate 34 vibrates in a wave shape by the action of the piezoelectric vibrator 38. A small hole 36 is formed in the antinode due to this vibration. For this reason, the small hole 36 portion is displaced by the maximum amount in the left-right direction on the paper surface of FIG. This allows the pressurizing chamber
The developer in 30 is cyclically pressurized, and from the small hole 36 to the developing chamber 44.
Gush out inside.

That is, from the state shown in FIG. 5A, the vibration plate 34 vibrates by the action of the piezoelectric vibrator, moves to the developing chamber 44 side, and becomes the state shown in FIG. 5B. Next, the vibration plate 34 moves to the inside of the pressure chamber 30 due to the vibration, and pressurizes the developing solution in the pressure chamber 30.
When the vibrating plate 34 comes to the center of the vibration, the developing solution is pushed out to the developing chamber 44 side from the small hole 36 as shown in FIG. 5 (C).
Further, the vibration plate 34 moves to the pressure chamber 30 side and presses the developing solution. In this state, as shown in FIG.
The developing solution extruded from the liquid tends to be spherical due to its surface tension, and the small holes 36 of the developing solution start to be narrowed. When the vibrating plate 34 further vibrates from this state and moves to the developing chamber 44 side, as shown in FIG.
It becomes liquid and is repelled and ejected. According to this principle, the developing solution becomes liquefied from a plurality of small holes 36 provided in the vibrating plate 34 and is atomized into the developing chamber 44, applied on the surface of the photosensitive material, and the photosensitive material is developed. .

As a usage example utilizing such a principle, Japanese Patent Publication No. 62-44
The fuel supply devices shown in Japanese Patent Publication No. 989 and Japanese Patent Publication No. 62-2858 are proposed.

The small hole 36 is formed at a position corresponding to an antinode when the vibration plate 34 vibrates in a wave shape. For this reason, the vibrating plate 34 is formed at a position where it is displaced to the maximum, so that the pressing force for pressing the developer in the pressurizing chamber 30 is maximized. Further, since the small hole 36 is formed in the belly portion, the developing solution jetted from the small hole 36 is jetted to the electrophotographic film 22 along the substantially horizontal direction and supplied to the electrophotographic film 22. That is, since the plurality of small holes 36 are jetted out in a substantially horizontal direction, the developing solution is uniformly supplied to the surface of the electrophotographic film 22.

Further, in this embodiment, since the piezoelectric vibrator 38 is used to vibrate the vibration plate 34, the apparatus becomes small and the developing unit 16
Can be formed in a small size.

After the developing solution is supplied to the electrophotographic film 22 and the developing process is performed, the excess developing solution remaining in the developing chamber 44 is collected by the gas-liquid separation device 80 to separate the liquid (developing solution) and the gas (air). It is separated and collected.

A predetermined frame of the electrophotographic film 22 having undergone the developing process in the developing section 16 is positioned in the drying section 18 by a film moving motor (not shown). In the drying section 18, warm air is blown onto the electrophotographic film 22 to dry the developing solution.

Next, a predetermined frame located in the drying section 18 is moved to the fixing section 20. Cold air is supplied to a predetermined frame that has moved to the fixing unit 20. After a lapse of a predetermined time, a xenon lamp (not shown) provided in the fixing section 20 emits light, the developer is fused and fixed on the surface, and the fixing step is completed.

By completing the above steps, the electrophotographic film
Recording of the image on 22 is completed.

In this embodiment, the supply of the developing solution to an electrophotographic film such as a micro film for recording a micro image has been described with reference to an example in which the present invention is applied, but the supply of the developing solution to a film used for silver halide photography is described. The present invention can also be applied.

As described above, according to the present invention, in the developing device for developing the electrostatic latent image formed on the surface of the photosensitive material, the porous development in which a plurality of small holes are formed corresponding to the developing area of the photosensitive material. An electrode, a pressure chamber provided on the side opposite to the photosensitive material of the porous developing electrode, a supply means for supplying the developer into the pressure chamber, and a small hole for periodically pressurizing the developer in the pressure chamber. Through the pressurizing means for ejecting the developing solution into the developing area in the form of liquid droplets,
Therefore, it has an excellent effect that the developing solution can be uniformly supplied to the surface of the photosensitive material without waste and the developing electrode can be downsized.

[Brief description of drawings]

FIG. 1 is a sectional view taken along line II of FIG. 2 showing a developing portion of a process head which is an example of a developing device.
FIG. 3 is a perspective view showing a process head, FIG. 3 (A) is a perspective view showing a developing section, FIG. 3 (B) is a perspective view showing another example of the developing section, and FIG. FIG. 5 (A) to FIG. 5 (E) are cross-sectional views showing the relationship with the film, and FIG. 5 (A) to FIG. 5 (E) are explanatory views showing a state in which the vibrating plate vibrates and the developing solution is ejected. It is a circuit diagram showing the connection of. 10 …… Process head, 16 …… Developing section, 30 …… Pressurization chamber, 34 …… Vibration plate, 35 …… Bias power supply, 36 …… Small hole, 37 …… Power supply, 38 …… Piezo vibrator, 40 , 42 …… left and right frame, 44 …… developer chamber, 70 …… air pump, 72 …… pipe, 74 …… developer bottle.

Claims (1)

[Claims] 1. A developing device for developing an electrostatic latent image formed on a surface of a photosensitive material, wherein a porous developing electrode having a plurality of small holes corresponding to a developing area of the photosensitive material, and a photosensitive electrode of the porous developing electrode. A pressure chamber provided on the side opposite to the material, a supply means for supplying the developer into the pressure chamber, a developer in the pressure chamber is periodically pressurized to develop the developer in a droplet state through small holes. A developing device, comprising: a pressing unit that ejects the toner to a region.