JPS59101667A - Non-impact color printer - Google Patents

Abstract

PURPOSE:To record a character or a pattern by a desired color number, and also to simplify a mechanism by providing a photosensitive body at every color, exposing each of them by an information corresponding to each color, and overlapping and transferring a picture of each color on form. CONSTITUTION:Three photosensitive bodies 1, 2 and 3 are arranged in one line, and a laser light 11 of a red information is irradiated to the photosensitive body electrostatically charged by an electrifier 4. That is to say, a light from a laser light source 5 is controlled to on and off or strength and weakness corresponding to the red information by an optical modulator 6, a linear scanning is executed by a polygon mirror 7, and an image is formed on the surface of the photosensitive body by an optical system. A developing device 21 is an inverted developing device against red, and a red toner is made to adhere onto a part from which electrostatic charge is eliminated by exposure of the laser light 11. A form 31 is transferred by a part of a transfer device 9 of the photosensitive body 1 by a carrying device 32. When the transfer is ended, a toner image of the photosensitive body 1 is cleaned by a cleaning device 10. The form 31 on which a three-color image is transferred is fixed by a fixing device 33 of a heating system or an optical flash system, etc., and a full color print is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a non-impact color printer that records multicolored characters or figures on paper by developing and transferring an electrostatic image written on a photoreceptor using a laser beam.

2. Description of the Related Art Non-impact printers, which electrophotographically record characters or figures on paper using laser light, are often used to display computer output. Displays have already been used to display computer output in multiple colors, but non-impact color printers that record in multiple colors on paper have not yet been put to practical use. However, in order to cope with the diversification of information, there is a strong demand for practical use of non-impact printers.

In order to meet such demands, it is an object of the present invention to provide a non-impact color printer that can record characters or figures in a desired number of colors and has a simple mechanism.

The purpose of this is that a horn impact color printer has multiple photoconductors, a developing device that develops each photoconductor in a different color, and an electrostatic potential for an image corresponding to each developed color on each photoconductor. A laser exposure device that forms an image, and a conveying device that conveys recording paper in contact with a photoreceptor so that the electrostatic latent images are developed and the color images are superimposed and transferred to the same position on the paper surface. achieved by

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows a three-color non-impact printer according to the invention, in which three photoreceptors 1, 2, and 3 are arranged in a row.

The photoreceptor charged by the charger 4 is irradiated with a laser beam 11 for red information. That is, the light from the laser light source 5 is controlled by the optical modulator 6 to be on, off, or strong or weak depending on the red information, the polygon mirror 7 performs direct scanning, and the optical system 8 forms an image on the surface of the photoreceptor. The developing device 21 is a reversal developing device for red, and is used to attach red toner to the portion where the charge has been erased by exposure to the laser beam 11. The paper 31 is transferred to the transfer device 9 of the photoreceptor 1 by the conveyor 32 . After the transfer is completed, the toner image on the photoreceptor 1 is cleaned by a cleaning device IO. Although the photoreceptor 2 is not shown, an electrostatic latent image with no charge for blue is generated by exposure to a laser beam 12 with blue information in the same manner as with red information, and a blue toner image is obtained by reversal development by a developer 22. This blue image is transferred by the transfer device 9 of the photoreceptor 2 onto the paper 31 on which red printing has been completed. At this time, the printing process is synchronized so that the red and blue images are aligned. Similarly, a yellow image is generated on the photoreceptor 3 through laser light exposure 13 and transferred to the paper 31 by a synchronized printing process. Thereafter, the paper 31 onto which the three-color image has been transferred is fixed by a fixing device 33 of a thermal type or optical flash type to obtain a full-color print. Note that three fixing devices may be provided so that fixing is performed after each color transfer.

Figure 2 (al (bl) indicates the arrangement of three-color printing, and when printing the area 40 of the letter E shown in Figure 2 (&) on 31 sheets of paper in all colors and making it black, a part 41 is enlarged. As shown in Fig. 2 (bl), a red spot 42, a blue spot 43, and a yellow spot 44 are printed so as to be adjacent to each other.The diameter of each spot 42 to 44 is 10 to 508 m, for example, 30 μm. If you print in this way, the three colors will not overlap, so you can obtain color prints with good tone.Additionally, one photoreceptor is added to provide a black photoreceptor, and black prints can be made. This will give you normal black printing.

Laser light digital signals with color information are processed using the same signal processing methods used in conventional monochromatic electrophotographic laser printers. In other words, the printed information is processed by a computer,
The signal is applied to the optical modulator 6 to modulate the laser beam according to the writing.

This printed information can be obtained by reading a color-separated image using a filter adapted from the original drawing and temporarily storing each color information in a computer, or by storing character information and graphic information in advance in a computer. It may be kept.

As described above, the present invention provides a photoreceptor for each color, exposes each photoreceptor with information corresponding to each color, and transfers images of each color onto paper in an overlapping manner, and does not require a complicated mechanism.
Since the developer of each color is not mixed and the toner image of each color can be formed in separate areas, a color image with good tone can be obtained. Furthermore, it is convenient because it is possible to perform monochrome or two-color printing by using only a limited number of photoreceptors, and the effects obtained are extremely large.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a color laser printer according to an embodiment of the present invention, and FIG. 2 (al and bl are examples of printing,
ta+ is a plan view of the entire print; fb) i is an enlarged view of a portion of the hem. 1... Red developing photoreceptor, 2... Blue developing photoreceptor, 3...
・Yellow bacteria photoreceptor, 4... Charger, 5... Laser light source, 6... Light modulator, 9... Transfer device, 21.22...
・Developer, 31...Transfer paper, 32...Transporter. E 2 (Q) Figure (b) 10-50. g

Claims (1)

[Claims] 1) A plurality of photoconductors, a developing device that develops each photoconductor in a mutually specific color, and a laser exposure device that forms an electrostatic latent image of an image corresponding to each developed color on each photoconductor. and a conveying device that conveys the recording paper in contact with the photoreceptor so that the color images generated by developing the electrostatic latent images are transferred to the same position on the paper surface in an overlapping manner. color printer.