JPH0566642U - Image forming device - Google Patents

Abstract

(57) [Abstract] [Purpose] Eliminate the unnecessary pre-lighting operation of the fluorescent print head of the fluorescent writing device and effectively utilize it. After the lighting, while the fluorescent substance and the filament in the fluorescent writing device are in a stable thermal state, exposure is performed so that almost all the microcapsules in the region A of the photosensitive member 1 corresponding to the tip of the transfer member 8 are cured. Then heat develop. Subsequently, the image area B and the area C corresponding to the rear end of the transfer member 8 are exposed,
When heat development is performed and the transfer member 8 is superposed and pressed by the pressure transfer device 10, the front end portion and the rear end portion of the transfer member 8 are bordered in white.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an image forming apparatus that forms an image using a visible light-sensitive heat developing material.

[0002]

[Prior Art]

 There are various methods for forming a color image, and one of them is one utilizing the selective curability of microcapsules, for example, JP-A-61-278849. This is a photosensitive transfer type photothermographic material sensitive to visible light, and is a highly sensitive photosensitive member triggered by silver. As a specific example of performing color printing using this photosensitive member, there is JP-A-63-141 051. According to this publication, a configuration example including a laser and a wavelength converter is disclosed as an optical writing device, but it is not widely used in general and is expensive. Further, although the above-mentioned photosensitive member has high sensitivity, the sensitivity is considerably low as compared with a conventional photographic process, and the printing speed cannot be increased so much.

On the other hand, as an optical writing device other than the above, for example, a fluorescent print head as disclosed in JP-A-1-95073 can be cited. Since the fluorescent tube as in this example emits visible light and has high brightness, it is small and compact by applying it to the photosensitive member as described above, and it is possible to perform high-speed color printing. ..

[0004]

[Problems to be solved by the device]

 However, the above-mentioned conventional technique has the following problems.

First, regarding the fluorescent print head, since the fluorescent display tube used here is a kind of vacuum tube, the thermal state of the phosphor and filament is unstable immediately after the application of power for lighting. Therefore, the light emission amount is not constant. Normally, it takes about several seconds until the amount of emitted light stabilizes. Therefore, there was a waste of having to turn on the pre-light before the image formation.

On the other hand, regarding the pressure transfer in the image forming apparatus, in the image forming apparatus like this example, the exposed photosensitive member and the transfer member are superposed by applying a very large pressure. It is necessary to destroy the microcapsules. At this time, the part other than the image-exposed region of the light-sensitive member (particularly the part corresponding to the tip of the transfer member) is an unnecessary part because it is not the image itself, but the internal liquid component spilled out by the microcapsule destruction. Had adhered to the transfer member. For this reason, if the transfer member is forcibly peeled off, the output image may be damaged, and if the light-sensitive member is conveyed with the transfer member attached, it may cause paper jam or malfunction.

In addition, in a portion other than the image-exposed region of the photosensitive member (portion corresponding to the front end and the rear end of the transfer member), the liquid component inside the microcapsules that has flowed out bleeds upon pressurization to the transfer member. The contour of the transferred image was blurred, or unnecessary smear occurred on the transfer paper when the pressure transfer device was opened or closed.

The present invention solves the above problems in view of such a situation, and an object of the present invention is to effectively use the fluorescent print head by eliminating unnecessary pre-lighting operation, and to perform transfer after pressure transfer. An object of the present invention is to provide an image forming apparatus capable of easily peeling paper from a photosensitive film and obtaining a clear image.

[0009]

[Means for Solving the Problems]

 In the image forming apparatus of the present invention, a photothermographic material having a microcapsule in which at least a photosensitive material and a coloring material are encapsulated is provided on a support, and a control electrode controls electrons emitted from the cathode. After irradiating the fluorescent material provided on the anode part with a fluorescent writing device that emits visible light containing at least red, green, and blue components, the fluorescent material is superposed and pressed onto the transfer member to form an image on the transfer member. In the image forming apparatus for forming a sheet, the fluorescent writing device in an unstable state immediately after lighting exposes a region of the photosensitive member corresponding to the tip of the transfer member so that almost all microcapsules are cured. It is characterized by

Further, after image exposure, when the fluorescent writing device in a stable lighting state exposes a region of the light-sensitive member corresponding to the rear end of the transfer member so that almost all the microcapsules are cured. More desirable.

[0011]

【Example】

 The image forming apparatus of the present invention will be described in detail below with reference to embodiments.

FIG. 1 is a front sectional view showing an embodiment of the present invention. First, the operation of this machine will be described.

An unexposed continuous sheet-shaped photosensitive member 1 is housed in a cartridge 2, which is fed from here during operation and exposed by a fluorescent writing device 4 on an exposure table 3 to form a latent image. An image signal, a drive signal and the like are input to the fluorescence writing device 4 from a control device (not shown) so that appropriate exposure is performed according to a desired image. After that, the photosensitive member 1 is heated and developed by the heat developing device 6 through the conveying roller 5.

On the other hand, the cut sheet-shaped transfer member 8 accommodated in the paper feed tray 7 is sent out by the paper feed device 9 and is superposed on the photosensitive member 1 in synchronization with the image area formed on the photosensitive member 1. And pressure-transferred by a roller-pressure type pressure transfer device 10. The pressure unit of the pressure transfer device 10 is composed of three rollers, an upper roller 11, a middle roller 12, and a lower roller 13, and pressure transfer is performed between the upper roller 11 and the middle roller 12.

After that, the transfer member 8 is separated from the photosensitive member 1 by the separation roller 14 and discharged to the paper discharge tray 16 through the conveying roller 15. The photosensitive member 1 promotes the conveyance and separation of the photosensitive member 1. It is wound around a winding shaft 18 via a pinch roller 17.

Reference numeral 19 is a manual sheet feeding port, and 20 is a gas filter for removing gas generated in the machine.

The photosensitive member 1 and the transfer member 8 used in this embodiment are those described in JP-A-61-278849, and the photosensitive member 1 is sensitive to visible light and The microcapsules in the area irradiated with light are hardened by heat development. Then, the uncured microcapsules are crushed by the pressure, the color material inside is released and moves to the transfer member 8, and a full-color image can be obtained on the transfer member 8.

Next, the fluorescent writing device 4 will be described.

FIG. 2 is a schematic diagram showing a fluorescent writing device portion of the image forming apparatus of FIG. In the figure, as the fluorescent writing head 41, for example, one described in JP-A-1-95073 can be used. This is a kind of fluorescent display tube in which a cathode 42, a control electrode 43, various electrodes of an anode 44, a phosphor 45, etc. are arranged in a vacuum sealed with glass, so that visible light is emitted in the lower direction of the figure. Is becoming A lens 46 composed of a converging fiber array is provided below the fluorescent writing head 41, and a visible light image is projected on the photosensitive member 1 on the exposure table 3.

Since the present invention aims to obtain a full-color image, the fluorescent writing head 41 is divided into three blocks of dot groups corresponding to exposure of three colors of red, green, and blue, and each dot is divided into groups. Lenses 46 are individually provided for the groups.

As the phosphor 45 used here, a phosphor whose peak wavelength is blue-green is used in terms of light emission characteristics, life, and the like. Although it emits blue-green light when visually observed, since it contains red, green, and blue wavelength components and has high brightness, a latent image can be formed at high speed on the photosensitive member 1 described above. Then, as described above, a clear full-color image can be obtained on the transfer member 8 by pressure transfer after heat development.

In this embodiment, the photosensitive member 1 has an A4 width, and the fluorescent writing head 41 has 2550 dots for each color and has a resolution of 300 DPI.

In the above configuration, a method of curing almost all the microcapsules in the region of the photosensitive member 1 corresponding to the tip of the transfer member 8, in other words, a method of edging the tip of the transfer member 8 in front of the image in white Will be described.

First, an all-dot lighting signal is input to the fluorescent writing device 4 from a control device (not shown) to start lighting. At this time, due to the characteristics of the fluorescent display tube, the heat state of the phosphor and the filament is unstable, so the amount of light is not stable. However, the image signal is not recorded, and the exposure is for curing almost all the microcapsules, so even if the exposure amount varies a little, it is not much affected. Then, after the light quantity of the fluorescent display tube is stabilized, image exposure is performed according to the image signal, whereby a latent image corresponding to the image can be formed.

FIG. 3 is a diagram showing an exposure area of the photosensitive member 1. The photosensitive member 1 is exposed while being conveyed in the arrow D direction as described above. Since the phosphor 45 of the fluorescence writing device 4 contains all the red, green, and blue dyes, almost all the microcapsules coated on the support of the photosensitive member 1 will be processed in the next heat development step. It can be exposed as it is cured. Therefore, in the photosensitive member 1, almost all of the capsules in the area A corresponding to at least the tip of the transfer member 8 are exposed to light in a non-stable state of the fluorescent writing device 4 before the start of image writing to form a latent image for curing. It Then, the fluorescent writing head 41 writes an image in the image area B.

FIG. 4 is a diagram showing a photosensitive member and a transfer member conveyed to the pressure transfer device.

The exposed and heat-developed photosensitive member 1 is fed into the pressure transfer device 10 in the order of the already exposed and heat-developed region A and then the image region B. When the area A of the exposed and heat-developed photosensitive member 1 superposed on the transfer member 8 approaches between the upper roller 11 and the middle roller 12, the upper roller 11 and the middle roller 12 are closed and pressure transfer is performed. Done. Subsequently, the image area B is also pressed, but since almost all of the microcapsules in the area A are hardened, the transfer member 8 first has the area A at the leading end edged white, and subsequently, the image is transferred, and the transfer member 8 is also exposed. The member 1 and the transfer member 8 can be easily separated.

Next, the exposure of the region of the photosensitive member corresponding to the rear end of the transfer member will be described.

In FIG. 3, even when an image is written in the image area B of the photosensitive member 1 and the image signal ends, the photosensitive member 1 is conveyed and the area of the photosensitive member 1 corresponding to the rear end of the transfer member 8. C exposure is performed. Then, the microcapsules in the area C are hardened by heat development similarly to the area A, and are fed into the pressure transfer device 10 next to the exposure area A and the image area B as shown in FIG. When the exposed light-sensitive member 1 is superposed on the transfer member 8 in the pressure transfer device 10 and pressure transfer is performed, the region C 1 at the rear end is bordered in white. Therefore, even if the upper roller 11 and the middle roller 12 are opened and closed, white edges are clearly formed at the front and rear ends of the transfer member 8. Regarding the exposure of the area C described in this example, the fluorescent writing device 4 is in a stable state since a sufficient time has elapsed after lighting. Due to the characteristics of the fluorescent tube, it is not absolutely necessary to expose the area C, but it is not necessary to frequently turn on / off the fluorescent writing head when performing continuous exposure of a plurality of sheets, which will be described later, and it is practically possible to continuously light the lamp. Therefore, a more stable light amount can be obtained.

In the case of continuously outputting a plurality of sheets, as shown in FIG. 4, white background exposure is started from the area A ′ subsequent to the already exposed area C, and the image area B ′ is exposed. By repeating this, white edges are formed at the front and rear ends of the transfer member.

Regarding the transport speed of the photosensitive member 1, there is no particular speed difference between the areas A, A ′, C and the image area B described above. Even at the same speed, most of the microcapsules are hardened in the regions A, A ', and C, so that the image obtained on the transfer member 8 is not adversely affected in practical use. However, it is possible to further enhance the effect by lowering the transport speed as compared with image exposure.

In the present invention, the exposure is performed by fixing the fluorescent writing device and moving the photosensitive member, but the same result can be obtained by moving the fluorescent writing device and performing the exposure.

In the present invention, the heat-developable photosensitive material has been used for description, but the invention is not limited to this. An image is formed by pressure transfer utilizing the selective curability of microcapsules. It goes without saying that it can be widely applied to photosensitive materials.

[0034]

[Effect of the device]

 As described above, according to the present invention, almost all microcapsules of the photosensitive member are exposed in the region corresponding to at least the tip of the transfer member by the light emission until the heat of the phosphor and the filament in the fluorescent writing device is stabilized. When the photosensitive member and the transfer member are superposed and pressed by exposing so as to cure, the transfer member can be easily peeled off without the tip of the transfer member being attached to the photosensitive member. Therefore, there is an effect that it is possible to prevent paper jams and failures without impairing image quality.

Further, since a white edge can be formed on the transfer member, the output image has an effect that the contour is not blurred and a clear image can be obtained.

[Brief description of drawings]

FIG. 1 is a front sectional view showing an embodiment of the present invention.

FIG. 2 is a schematic diagram of a fluorescent writing device of the present invention.

FIG. 3 is a diagram showing an exposure area of a photosensitive member according to the present invention.

FIG. 4 is a view showing a photosensitive member and a transfer member conveyed to a pressure transfer device in the present invention.

[Explanation of reference numerals] 1 photosensitive member 2 cartridge 3 exposure table 4 fluorescent writing device 5 transport roller 6 heat developing device 7 paper feed tray 8 transfer member 9 paper feed device 10 pressure transfer device 11 upper roller 12 middle roller 13 lower roller 14 separation Roller 16 Paper ejection tray 17 Pinch roller 18 Winding shaft 19 Manual feed port 20 Gas filter 41 Fluorescent writing head 42 Cathode 43 Control electrode 44 Anode 45 Phosphor 46 Lens

Claims (2)

[Scope of utility model registration request] 1. A heat-developable photosensitive member having microcapsules in which at least a photosensitive material and a coloring material are encapsulated on a support, and electrons emitted from a cathode are controlled by a control electrode to be provided in an anode portion. The formed fluorescent material is irradiated with light and exposed by a fluorescent writing device that emits visible light containing at least red, green, and blue components, and then is superimposed and pressed on the transfer member to form an image on the transfer member. In the device, the fluorescent writing device in an unstable state immediately after lighting, exposes a region of the photosensitive member corresponding to the tip of the transfer member so that almost all microcapsules are cured. Image forming apparatus. 2. After the image exposure, exposing the area corresponding to the rear end of the transfer member of the photosensitive member by the fluorescent writing device in the stable lighting state so that almost all the microcapsules are cured. The image forming apparatus according to claim 1, wherein: