JPH0348586Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention exposes original information from a color original placed on a platen glass onto a photosensitive material, and uses a processing liquid that arranges the photosensitive material according to the development process. The present invention relates to an image forming apparatus that forms color images by sequentially passing through tanks.

[Background of the idea]

In recent years, the demand for color copying has increased, and color electronic copying machines have been released.
The image quality is insufficient, and it cannot be said that it fully satisfies the demand for color copying. Color copying machines using silver halide color photosensitive materials have also been proposed and put on the market.

In such color copying machines, direct positive silver halide color photosensitive materials are often used, and a reversal exposure process called reversal exposure is performed to form a positive image.

This reversal exposure means forms an exposure tube having an exposure window facing the path of the photosensitive material in the first processing liquid tank (first developing tank) in which the imagewise exposed photosensitive material is color-developed in the image exposure section. A light source in a lamp house provided above the exposure tube is made to emit light so that light can be uniformly applied to the photosensitive surface of the photosensitive material in the liquid. Therefore, since the outer surface of the exposure glass (transparent plate) fitted in the exposure window is in contact with the developer, when the developer in the processing solution tank is heated to the temperature required for development at the beginning of operation, the exposure The air inside the exposure tube condenses due to the temperature difference between the outer and inner surfaces of the glass.
The inner surface of the exposed glass sometimes fogged up. Therefore, due to this clouding, the balance of the amount of exposure light transmitted through the glass surface of the exposure window was disrupted, and uniform exposure was not performed, causing color unevenness in the coloring process.

[Purpose of invention]

This idea was developed to solve the above-mentioned problems, and it is possible to prevent dew condensation from forming on the inner surface of the exposure glass fitted in the exposure window for reverse exposure, thereby eliminating color unevenness during the color development process. The purpose is to provide a forming device.

[Structure of the idea]

In order to achieve the above object, this invention provides an image forming apparatus equipped with an inverted exposure window facing the path of the photosensitive material in a processing liquid tank for developing the photosensitive material after image exposure. It is constructed so that a heater is provided within the plate or near the inside thereof.

〔Example〕

Next, this invention will be explained based on embodiments shown in the accompanying drawings. Note that this invention is not limited to the embodiments shown here.

FIG. 1 is a schematic sectional view of an image forming apparatus according to this invention. In this figure, 10 is an image exposure section;
Reference numeral 20 designates a paper feeding section for the photosensitive material, 30 a conveying section, 40 a developing processing section, and 50 a drying section.

The image exposure section 10 includes a document table glass 11, a light source 12, a first mirror 13, a second mirror 14, a third mirror 15, a lens 16, and a shutter 17. A first scanning unit consisting of the light source 12 and the first mirror 13 moves parallel to the document table glass 11 to expose and scan the document, and a second scanning unit consisting of the second mirror 14 and the third mirror 15 moves parallel to the document table glass 11. It is mounted on a table and is adapted to move in the same direction as the first unit and at half the speed of movement of the first scanning unit. The above configuration of the image exposure unit 10 is almost the same as that used in known electrophotographic copying machines, etc., but by using an odd number of mirrors, the image is inverted and a latent image corresponding to the original image is created. The image is formed directly on the photosensitive surface of the photosensitive material. A diaphragm and a filter for color balance correction are installed on the principal point surface of the lens 16. The shutter 17 closes the exposure window 37 except during exposure scanning to prevent leakage of light to the photosensitive material conveying section 30.

The light-sensitive material used in this invention is preferably a positive-working silver halide color light-sensitive material in order to obtain a high quality copy image in which a positive image is formed by a development process after exposure. As such a positive silver halide color light-sensitive material, an internal latent image type is used. Further, the photosensitive material may be of a transmissive type or a reflective type.

The paper feeding unit 20 has a magazine 21 in which a photosensitive material is wound in a roll and stored in a light-tight manner removably installed therein, and also includes a drawer roller 23 that grips and pulls out the photosensitive material from the magazine 21, and a drawer. A cutting device 24 is provided to cut the end when it reaches a predetermined length.

The conveying section 30 includes a path 34 having conveying rollers 31, 32, and 33 for photosensitive material cut into a predetermined length, and a first accumulator 35 provided above the path 34 so as to be able to wind up and accommodate the photosensitive material. and a second accumulator 36 provided below the path 34. The conveyance roller 3
1 to 33 are capable of forward and reverse rotation, and when the photosensitive material is fed from the paper feed section 20, it rotates in the normal direction and is conveyed toward the first accumulator 35, so that the rear end of the photosensitive material reaches the image exposure section. When the exposure window 37 is reached above the exposure window 37, the photosensitive material is reversed and lowered toward the second accumulator 36. During the conveyance to the second accumulator 36, the original image is exposed to the photosensitive material passing through the exposure window 37 of the image exposure section 10. Therefore, the transport speed of the photosensitive material during this downward movement is synchronized with the light source scanning speed. The exposed photosensitive material housed in the second accumulator 36 is then returned to the first accumulator 35 by normal rotation of the conveyance rollers 31 to 33, and is then returned to the first accumulator 35 by a switching claw provided in the middle of the path 34. 38 is switched,
The image is sent to the development processing section 40. At this time, the emulsion side of the photosensitive material is upward, and the feeding speed is set to the first developing tank 41A, second developing tank 41B, bleach-fixing tank 41C, and first stabilizing tank 4 provided in the development processing section 40.
It is designed to synchronize with the feed speed of the transport rollers in each processing liquid tank 1D and second stabilizing tank 41E.

The photosensitive material that has passed through each of the processing liquid tanks 41A to 41E and has been developed is then dried in the drying section 50 with hot air by a warm air dryer 53 on its upper and lower surfaces while being sandwiched between a conveying roller 51 and a conveying wire 52. , and are discharged from the machine from a discharge roller 54.

The development processing section 40 is provided with a frame 40 that is removably provided below a light-shielding box 39 that shields the image exposure section 10 from light.
It is set within 0. Also, in the first developer tank 41A of the development processing section 40, there is a reversal exposure means 42 for applying reversal exposure to the photosensitive material in a solution after image exposure.
is provided. This reversal exposure means 42
As shown in the figure, an exposure tube 422 having an exposure window 421 fitted with an exposure glass (transparent plate) 426 facing the path of the photosensitive material is formed in the tank, and the lower surface of the light-shielding box 39 above the exposure tube 422. (Or a mounting base plate (not shown) installed separately from the light shielding box 39)
A lamp house 423 is installed in the lamp house. This lamp house 423 is divided into two rooms, and each room accommodates a light source 424 made of a cold cathode tube, and a color correction filter 425 is removably provided in front of the room. This color correction filter is used to provide the photosensitive material with light having components corresponding to the type of the photosensitive material.

The reason why the lamp house 423 is separated from the processing liquid tank and placed above it is to facilitate replacement work when the light source 424 inside the lamp house 423 or the color correction filter 425 installed in front of it needs to be replaced. This is to make it easier to carry out the process, and to prevent the lamp house from getting wet due to fluctuations in the level of the processing liquid filled in the processing liquid tank.

The light source 424 in the lamp house 423 is detected by a detector (not shown) provided while the photosensitive material is being sent from the conveyance section 30 to the development processing section 40, and emits light in response to the detection signal. This light source 42
The light rays from the exposure tube 422 are reflected from the reflective surface of the lower surface of the exposure tube 422 and are irradiated onto the photosensitive material through the exposure window 421.

As shown in the third figure, a protrusion 427 is provided on the outer surface of the exposure glass 426 fitted in the exposure window 421, extending perpendicularly to the traveling direction of the photosensitive material and extending over its entire width. The convex portion 427 is designed so that the emulsion surface of the photosensitive material facing the exposure window side and flowing down the passage does not come into contact with surfaces other than the convex portion 427 . That is, even if only the convex portion 427 is stained by the emulsion, the uniformity of the exposure light amount will not be impaired as long as the other portions are not contaminated.

Reference numeral 428 denotes a heater for heating the inner surface of the exposure glass 426 fitted in the exposure window 421, and the heater 428 is used at the beginning of operation when the developer in the processing solution tank is heated to the temperature required for development. This is to eliminate the temperature difference between the outer surface side and the inner surface side of the exposure glass, the outer surface of which is in contact with the developer, and to prevent the air inside the exposure tube from condensing on the inner surface of the exposure glass.
The heater 428 may be one in which a nichrome wire is embedded within the thickness of the exposure glass, a transparent film in which a nichrome wire is embedded is adhered to the inner surface of the exposure glass, or other materials. In this case, it is preferable that the nichrome wire is embedded in a zigzag pattern in a direction perpendicular to the running direction of the photosensitive material. That is, this is to prevent the amount of light hitting each part of the photosensitive material from being inhibited by the nichrome wire.

In addition, when a transmission-type light-sensitive material is used as the positive-working silver halide color light-sensitive material used in this invention, it is necessary to make the processing time longer than that of a reflection-type photosensitive material, or to In order to obtain good image quality with any reflective photosensitive material, it is possible to make the light intensity and filter of the light source for inversion exposure variable. It is also possible to perform sub-exposure outside the liquid beforehand. In this case, the light source for sub-exposure can also be used as the light source for reverse exposure.

In addition, in order to make these things more concrete, the magazine containing the photosensitive material is provided with an indication as to whether it is a reflective type or a transmissive type, and an indication that allows identification of the photographic characteristics of each type. When installed, the device will automatically recognize this display and change the conveyance speed of the photosensitive material in the processing tank, and will automatically adjust whether sub-exposure is possible and its light intensity, the light intensity of reverse exposure, and the variable light intensity of the filter. You can also. In this case, it is preferable to change the color temperature as well as the amount of light, and the adjustment of reversal exposure is not only performed for the difference in light-sensitive materials such as reflective or transmissive, but also for the characteristics of reflective light-sensitive materials. Since there may be different types of light-sensitive materials, it is more preferable to provide optimal reversal exposure suitable for each material.

[Effect of idea]

As explained above, this invention is applicable to an image forming apparatus equipped with an inverted exposure window facing the path of the photosensitive material in a processing liquid tank for developing the photosensitive material after image exposure. Because it is characterized by a heater installed inside or near the inside of the tank, the processing solution inside the processing tank is heated at the beginning of the power supply, and at the same time the inner surface of the glass is also heated by the heater. This eliminates the difference in temperature between the liquid temperature and the inner surface of the glass, effectively preventing dew condensation from forming on the inner surface of the glass, and preventing fogging, so that the amount of light that hits each part of the photosensitive material that is irradiated is always uniform, and the color is created during the coloring process. This has an excellent effect of not causing unevenness.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an image forming apparatus that is an embodiment of this invention, FIG. 2 is an enlarged sectional view of a reversal exposure means, and FIG. 3 is a perspective view of an exposure window. 40...Development processing section, 41A to 41E...Processing liquid tank, 42...Reverse exposure means, 421...Exposure window, 422...Exposure tube, 423...Lamp house, 424...Light source, 426...Transparent light plate, 427
...Protrusion.

Claims (1)

[Claims for Utility Model Registration] (1) In an image forming apparatus equipped with a reversal exposure window facing the path of the photosensitive material in a processing liquid tank for developing the photosensitive material after image exposure, An image forming apparatus characterized in that a heater is provided in or near the inside of a transparent plate. (2) Utility model registration claim No. 1, in which the heater has a nichrome wire embedded in a transparent plate.
The image forming apparatus described in . (3) The image forming apparatus according to claim 1, wherein the heater is a film in which a nichrome wire is embedded between layers and is adhered to the inside of a transparent plate. (4) The image forming apparatus according to claim 2 or 3, wherein the nichrome wire is wired in a direction perpendicular to the traveling direction of the photosensitive material.