JPH03217868A - Method and device for forming color image - Google Patents

Abstract

PURPOSE:To perform the recording of plural sheets at a high speed, to save the consumption of a coloring material and to reduce running cost by continuously forming the image at every color on specified number of sheets and housing a recording medium in a housing part in a device while switching a developing device. CONSTITUTION:A cut paper type recording sheet 2 from a paper deeding device 1 is fed to a transfer electrostatic charger 4 by a paper feeding roller 3 in synchronism with a photosensitive drum 5 and a 1st color toner image is transferred to the paper 2, which is housed in a recording paper intermediate stacker 15 through a fixing device 13 and a switching device 14. When the specified number of sheets are stacked, a multicolor developing device 9 is rotated to switch to a 2nd color toner image and the sheet 2 is fed to a transfer position by a roller 18 from the bottommost sheet in the stacker 15. After transferring and foxing the 2nd color image, the sheet 2 is returned to the top of the stacker 15. The recording paper where a color image is completed by repeating the above operation and superposing four colors is guided by the device 14 to b fed to a paper ejection stacker 16. Since a color switching action is reduced, necessary time for the action and the consumption of the coloring material are saved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is a method for forming a plurality of images on a recording medium such as recording paper using a color image forming apparatus that forms color images on a recording medium such as a recording paper by a method such as an electrophotographic method or a thermal transfer method. The present invention relates to a method and apparatus for obtaining the same.

[Conventional technology]

Conventional thermal transfer type color image forming devices use an ink donor film coated with heat-melting ink or heat-sublimation ink of three colors: yellow, magenta, and cyan, or four colors including black. A color image is formed by overlapping images, using a film in which each page is coated with ink of each color, and each page is recorded using a predetermined coloring material in a predetermined order. A method is known (JP-A-1-209174).

In addition, in electrophotographic color printers and color copying devices, an image formed with a single color toner on a photoreceptor drum is transferred to recording paper wrapped around a transfer drum, and toner images of second and subsequent colors are similarly transferred. A field-sequential recording method is known. In this case, a plurality of color developing devices are rotatably arranged around a cylindrical photoreceptor and are configured to contact the photoreceptor one after another (Japanese Patent Laid-Open No. 1-I84139
) [Problems to be Solved by the Invention] The above-mentioned prior art devices had the following problems. In the thermal transfer surface sequential recording method, ink of a predetermined color is applied to each area corresponding to one page, so even if a page contains many non-image areas, a certain area of ink film is consumed and running costs are high. It had In electrophotographic field-sequential recording, the developing device used is changed when changing colors, so when recording multiple sheets, it is necessary to change the developing device four times for each recording, which takes time. Was.

It is an object of the present invention to solve these problems, to enable high-speed recording of multiple sheets, to save on the coloring material consumed, and to realize low running costs.

[Means to solve the problem]

The color image forming method and apparatus of the present invention is a color image recording method in which images made of color materials of multiple colors are formed on a recording medium, and when recording multiple sheets, a plurality of consecutive images of a first color are continuously formed. Then, images in the second color are continuously formed on the plurality of recording media on which the images in the first color have been formed, A color image is formed by forming images of three or more color materials in the same manner.

〔Example〕

Next, the present invention will be explained based on examples. FIG. 1 is a diagram showing the configuration of a color image forming apparatus showing an embodiment of the present invention.

The figure shows an electrophotographic color printer.

Image formation is carried out by a so-called Carlson process, and a charger 7, an exposure device 8, a multicolor developing device 9, a transfer charger 4, a static elimination lamp 10, and a cleaning device 11 are sequentially arranged around a photosensitive drum 5 that rotates in the direction of an arrow 6. has been done. The multicolor developing device 9 has four internal parts 9-1, 9-2, and 9-.
The electrostatic latent image on the photosensitive drum is formed by the developing device which is divided into 3 and 9-4, each having a dry developing device of a corresponding color, and which is rotatably supported about the developing device rotation center 9-5 and comes into contact with the photosensitive drum 5. Develop. Furthermore, there is a fuser 13 in the device.
, a paper discharge stacker 16, a switching device 14, a recording paper intermediate stacker 15, and a conveyance device 12 appropriately arranged in the recording paper conveyance path.

Next, the operation of forming a plurality of identical color images will be explained. The first sheet of cut paper-like recording paper 2, which is a recording medium sent out from the paper feeder 1, is placed on the photosensitive drum 5.
The transfer charger 4 of the transfer section is activated by the paper feed roller 3 in synchronization with the rotation of the
The toner image of the first color on the photosensitive drum 5 is transferred thereto. The recording paper onto which the first color toner image has been transferred is sent to a fixing device 13, where the first color toner image is thermally fixed on the recording paper. Further, guided by the switching device 14, the recording paper is sent to and stored in the recording paper intermediate stacker 15 with the recording paper presser 17 raised.

Similarly, toner images of the first color are formed on a desired number of recording sheets, and a predetermined number of recording sheets having the toner images of the first color are stored in the intermediate recording sheet stacker 15.

Next, a second color image is formed. The multicolor developing device 9 is rotated to switch the developing device in contact with the photosensitive drum to the second color developing device. Next, the lowest recording paper fed into the recording paper intermediate stacker 15 first is sent to the transfer position by the recording paper intermediate stacker feed roller 18, and the second color toner image formed on the photosensitive drum 5 is transferred thereto. The image is then fixed by the fixing device 13. The first sheet of recording paper having the toner images of the first and second colors is again sent to the recording paper intermediate stacker 15 and stored at the top. Similarly, for the second and subsequent sheets, a second color toner image is formed superimposed on the first color toner image, and a predetermined number of recording sheets having the second color toner image on the first color toner image are formed on the recording paper. It is stored in the intermediate stacker 15.

The third color toner image formation is performed in the same manner. Next, when forming the fourth color toner image, the switching device 14 is switched and the recording paper is set to be sent to the paper discharge stacker 16.

The recording paper on which the toner images of the first color, second color, third color, and fourth color are formed to form a color image is passed through the fixing device 13, and is sequentially sent to the paper output stacker 16 starting from the first sheet. is stored. After forming a four-color image on a predetermined sheet, the recording paper intermediate stacker-1
5, all the recording paper inside is fed out and becomes empty.

Next, a second embodiment will be explained using FIG. 2. Around the photosensitive drum 31, means from charging to cleaning are arranged as in the previous embodiment.

However, this embodiment differs from the previous embodiments in that the electrostatic latent image is developed using a liquid developer. That is, a developer tank 32 containing liquid developers of four colors and a developer 33 are connected by a pipe 34, and a developer of a specific color is transferred to the developer tank 3.
2 to the developing device 33, and when switching colors, a developer of a different color can be supplied to replace the developer of the previous color with the developer of the later color.

Next, the image forming operation will be explained. A developer of the first color is supplied to the developing device 33, and a predetermined number of recording sheets on which a toner image of the first color has been formed as in the first embodiment are transferred to the intermediate stacker of recording sheets.
It is stored in 35. Next, from the developer tank 32 to the developer 3
After the second developer is supplied to No. 3 and the first developer is recovered to a state where it can be developed with the developer of the second color, an image of the second color is formed in the same manner. The following steps up to the formation of the fourth color image are the same as those in the previous embodiment, and the explanation thereof will be omitted.

A third embodiment will be explained using FIG. 3. This embodiment is a thermal transfer type color image forming apparatus.

a thermal head 41 having a length equal to the recording width, a multicolor ink donor film support device 42, and a paper feed device 43;
It has a recording paper intermediate stacker 44, a paper discharge stacker 1, and a paper conveyance path 45 that connects these.

The multicolor ink donor film support device 42 includes four sets of ink donor film support devices 42-1 and 4, each including a supply section 47 and a winding section 48 for a specific color ink donor film.
2-2, 42-3, and 42-4, and are rotatably supported about a rotating shaft 49. Thermal head 41
In the standby state, as shown by 50, the ink donor film is moved to a rear position without contact with the ink donor film, and during recording, it moves to the front and is pressed against the recording paper via the ink film.

Next, the operation of recording a plurality of color images will be explained. When forming an image on the first sheet and in the first color, the thermal head 41 is pressed against the ink donor film at the recording position using the first ink donor film support device 42-1.

The recording paper after the image formation is sent to the recording paper intermediate stacker 44 by the switching device 51 and stored therein. The second and subsequent sheets are similarly subjected to first color image formation and stored in the recording paper intermediate stacker 44. Next, the thermal head 41 is moved to the standby position 50, and the multicolor ink donor film support device 42 is rotated 90 degrees about the rotation axis 49 to put the second ink donor film 42-2 in the recording state and form a second color image. conduct. Thereafter, image formation is performed in the same manner up to the third color. The recording paper on which the image of the fourth color has been formed is sent to the paper discharge stacker 46 and stored therein by switching the switching device 51 to the state shown by the broken line in the figure.

Although the above description has been made regarding the case in which a plurality of identical images are continuously formed, it is equally effective in the case where a plurality of different images are formed.

〔Effect of the invention〕

When forming color images on a plurality of sheets, the present invention has the effect that the color switching operation only needs to be performed four times for a plurality of consecutive sheets, and the time required for color switching can be shortened. In addition, since the number of color switching operations can be reduced, color material consumption due to color switching is reduced, and since the ink donor film is not consumed in areas corresponding to non-image areas, running costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of a color image forming apparatus showing an embodiment of the present invention. FIG. 2 is a diagram showing the configuration of a color image forming apparatus showing another embodiment of the present invention. FIG. 3 is a diagram showing the configuration of an image forming apparatus showing still another embodiment of the present invention. Paper feeding device 1, 43 Recording paper 2 Paper feeding roller 3 Multicolor developing device 9 Conveying device 12 Switching device 14, 51 Recording paper intermediate stacker 15, 35, Paper discharge stacker
16, 46 Recording paper intermediate stacker feed roller developer tank 32 Developing device 33 Multicolor ink donor film supporting device Paper transport path 45 44 18 42 Above

Claims (2)

[Claims] (1) In a color image recording method for forming images made of color materials of multiple colors on a recording medium, when forming multiple images, continuously forming multiple images of the first color,
Next, a plurality of images of the second color are formed on the plurality of recording media on which the images of the first color have been formed, and then a plurality of images of the coloring materials of the third and subsequent colors are similarly formed to form a color image. A color image forming method characterized by forming. (2) In a color image recording device that forms an image made of color materials of multiple colors on a recording medium, when the storage section that stores multiple recording media is provided and images are formed on multiple sheets,
A plurality of images of the first color are formed and stored in the storage section, and then, to form an image of the second color, the plurality of recording media on which the images of the first color have been formed are supplied from the storage section. conduct,
Furthermore, a color side image forming apparatus is characterized in that it is configured to form a color image by similarly forming a plurality of images of color materials of a third color and subsequent colors.