JPH0460678A - electrophotographic equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrophotographic apparatus, and more particularly to an electrophotographic apparatus that forms a visible image on photosensitive paper and does not perform transfer.

[Prior Art] The basic configuration of a conventional electrophotographic apparatus will be described with reference to FIG. In an electrophotographic apparatus that directly forms an image on photosensitive paper without transferring the image to general paper, 8-photo paper 11 conveyed from a paper feed tray 10 is wound around a drum 12. Around the drum 12, in order along the rotation direction a, there are a charging device 13 for charging the photosensitive paper 11 on the drum 12, an exposure device 14 for exposing the photosensitive paper 11 with an original image using laser light, and the photosensitive paper 11. A developing device 15 for developing the upper latent image, a static eliminating device 16 for removing residual charges, and a separating device 17 for separating the photosensitive paper 11 after image formation from the drum 12 are provided. The paper 11 is sequentially processed by each device, and after an image is formed on the surface of the photosensitive paper 11, it is discharged to a paper discharge tray 18.

In such conventional devices, the color of the photosensitive paper 11 is the limit for the whiteness of the image, and the photosensitive paper must be white. Furthermore, in order to increase the sensitivity of the photosensitive paper 11, it has been common practice to mix a sensitizing dye into the photosensitive paper.

[Problem to be solved by the invention] By the way, with photosensitive paper containing zinc oxide, titanium oxide, etc., which forms an image directly on the paper without transfer, it is necessary to add sensitizing dyes to improve the sensitivity range. ing. Rose Bengal, fluorescin, etc. are known as sensitizing dyes. Sensitizing dyes have a unique color, so if they are mixed in in large quantities, the originally white photosensitive paper containing zinc oxide, titanium oxide, etc. will become the same color as the sensitizing dye, and the whiteness of the photosensitive paper will decrease. be damaged. On the other hand, if the amount of sensitizing dye is reduced so as not to impair the whiteness of the photosensitive paper, there is a problem in that the sensitivity decreases.

The present invention solves the above-mentioned problems, and after forming a visible image on the surface of the photosensitive paper, the sensitizing dye mixed in the photosensitive paper is bleached to whiten the photosensitive paper. It is an object of the present invention to provide an electrophotographic apparatus capable of obtaining high-quality white color even on photosensitive paper whose whiteness is lowered due to the contamination of a sensitive dye.

[Means for Solving the Problems] In order to achieve the above object, the present invention has image forming process means such as charging, exposure, and development, and uses electronic technology to form a visible image on photosensitive paper using these process means. In a photographic device, light containing ultraviolet light is irradiated onto photosensitive paper on which a visible image has been formed on the surface through development processing by a developing means, thereby fading the aggravating dye contained in the photosensitive paper and turning the photosensitive paper white. It is equipped with means for whitening the photosensitive paper.

[Function] According to the above configuration, after the development process is completed and a visible image is formed on the photosensitive paper, the sensitizing dye contained in the photosensitive paper is irradiated with light containing ultraviolet rays. The color fades and the photosensitive paper becomes white.

[Example] Hereinafter, an example of the electrophotographic apparatus of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 shows the configuration of this electrophotographic apparatus. The apparatus is provided with a drum 12 that can rotate in the direction a in the figure, and around it, a paper feed tray 10, a charging device 13, exposure device 14, developing device 15, static eliminator W16, and separation device 1
7 is provided. The difference from the conventional device is that the separation device 1
Next to 7, a photosensitive paper whitening means 2o is provided.

FIG. 2 shows details of the structure of the photosensitive paper whitening means 2o.

The means 20 is arranged so that a whitening light source 21 that emits white light including ultraviolet rays and a light source cover 22 illuminate the photosensitive paper 11 conveyed by the photosensitive paper conveyor belt 23.
is placed opposite. A light shielding plate 24 is provided between the light source cover 22 and the photosensitive paper conveying belt 23 to block the whitening light source 2.
It is covered to prevent the light emitted from one from leaking to others. It is effective to use a source that emits a large amount of ultraviolet rays, such as a mercury lamp, as the whitening light source 21.

Next, the operation of the electrophotographic apparatus of this embodiment will be explained. The photosensitive paper 11 is held on a paper feed tray 1o, and is wound around a drum 12 when forming an image. When the photosensitive paper 11 is wound, the drum 12 rotates in the direction of arrow a in the figure, and the photosensitive paper 11 is sequentially sent to the charging device 13, the exposure device 14, the developing device 1f15, and the static eliminator 16, where a visible image is formed. After being formed, it is separated from the drum 12 by the separating means 17 and conveyed to the photosensitive paper whitening means 20. When the photosensitive paper on which a visible image has been formed is conveyed to a predetermined position inside the light-shielding plate 24 by the conveyor belt 23, the whitening light source 21 is turned on for a predetermined period of time, and the sensitizing dye contained in the photosensitive paper 11 is exposed. is faded to make the photosensitive paper 11 white.

It should be noted that photobleaching of dyes is generally understood to occur due to oxidation reactions, and it has also been found that addition of radical initiators and transition metal ions can accelerate discoloration in addition to UV light irradiation. .

The present invention is not limited to the configuration of the above embodiment,
Various changes can be made without departing from the spirit of the invention. For example, in this embodiment, the whitening light source 21 is used as the photosensitive paper whitening means 2o to bleach the sensitizing dye, but it is also possible to perform thermal decomposition using a heater or the like, or use the method described above. It is also possible to use such fading means. Further, when the whitening light source 21 is used in the photosensitive paper whitening means 20 as in this embodiment, by providing the whitening light source 21 around the drum 12, it can also be used for optical static elimination.

[Effects of the Invention] As described above, according to the present invention, in an electrophotographic device that directly forms an image on photosensitive paper, whiteness, although high, can be achieved by mixing a sensitizing dye into the photosensitive paper. By irradiating the missing paper with light after forming an image, the photosensitive paper can be whitened and a high-quality image can be formed.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of an electrophotographic apparatus according to an embodiment of the present invention;
FIG. 2 is a block diagram of a photosensitive paper whitening means provided in this apparatus, and FIG. 3 is a block diagram of a conventional electrophotographic apparatus. DESCRIPTION OF SYMBOLS 11... Photosensitive paper, 12... Drum, 13... Charging device, 14... Exposure device, 15... Developing device, 16
... Static eliminator, 20... Photosensitive paper whitening means, 21.
...Whitening light source. Applicant Brasser Industries Co., Ltd.

Claims (1)

[Claims] (1) In an electrophotographic device that has image forming process means such as charging, exposure, and development, and forms a visible image on photosensitive paper using these process means, the visible image is formed on the surface through development processing by the developing means. An electrophotographic apparatus comprising a photosensitive paper whitening means for bleaching a sensitizing dye contained in the photosensitive paper to whiten the formed photosensitive paper.