JPS60217377A - Multicolor recording method - Google Patents

Abstract

PURPOSE:To perform multicolor recording in a high speed with a simple constitution by developing two or more kinds of electrostatic latent image simultaneously, developing one kind of latent image in the unsaturated state and developing it with a toner of another color. CONSTITUTION:The surface of a recording drum 17 is scanned by a laser beam 19 which is modulated to two kinds of intensity in accordance with the position and colors of a picture to be recorded, and a latent image is formed on the surface. The latent image is developed with the first toner 36 by the first developing part 25 so that it is not saturated for a developable toner saturation quantity, and next, the latent image is developed with the second toner 37 by the second developing part 29. The toner image formed on the recording drum 17 in this manner is transferred to a receptive paper 32 by the action of an electrifier 33 and is fixed by a fixing part 35.

Description

Detailed Description of the Invention Industrial Application Field 2 H) The invention is based on the printing of color image output information such as characters, symbols, graphs, etc. on a recording medium in an output device of an information processing device such as a computer. This relates to a multicolor recording method for copying.

Conventional configurations and their problems The conditions required for image output devices of information processing devices such as electronic computers include excellent image quality, high-speed recording, small size and simple devices, and recent improvements. It is required to color output images such as characters, symbols, graphs, etc.

FIG. 1 shows an example of a two-color recording apparatus using electrophotography, which has been conventionally proposed as an apparatus for performing such multicolor recording. FIG. 2 shows the potential levels of each process performed with this device. The multicolor recording method using this apparatus will be explained below. In FIG. 1, reference numeral 1 denotes a recording drum having a photosensitive layer on its surface, the surface of which is uniformly positively charged by a charger 2 in a first step. The potential level on the surface of the recording drum 1 at this time is shown in FIG. 2a [Vl. Next, in the second step, as the recording drum 1 rotates in the direction of the arrow, the charge is partially removed from the surface by the light beam 3a projected by three vanes from the first exposure section 3, corresponding to the image to be recorded. 1 latent image is formed. The potential level in this state is shown in FIG.

Next, in the third step, the first latent image is developed in the first developing section 4 using the first colored toner. At this time, a bias voltage of Vb+ is applied to the recording drum 1 by the power supply 6 to the developing device 4a of the first developing section 4, and the positively charged first colored toner is applied only to the first latent image on the recording drum 1. arrive. The potential level in this state is shown in FIG. 2C. 14 shows how positively charged first colored toner is deposited to form a stain and fill the hole in the bell. Next, in a fourth step, the second exposure unit 6 exposes the portion other than the portion exposed in the second step to a light beam 6a corresponding to the image to be recorded. Next, in the sixth step, the second developing section 7 performs development using the second colored toner in the same manner as in the third step. 4th. The state of the potential level in the sixth step is shown in Figure 2.6.
Shown in e. The toner image formed on the recording drum 1 as described above is transferred onto the receiving paper 1o by the charger 9 and sent out. After the transfer, the surface of the recording drum 1 is subjected to re-cleaning in the cleaning section 11 and is reused.

In the conventional multicolor recording method, multicolor recording is obtained as described above, but this method has the following drawbacks. Since it is necessary to provide an independent exposing section and developing section for each color to be recorded, the apparatus becomes more complex and large in size, especially as the number of colors to be recorded increases. Furthermore, since each color is exposed in a separate process, the synchronization control of the recording drum rotation and the exposure timing for positioning the color rotation becomes complicated.

As another conventional example, as disclosed in Japanese Patent Application Laid-Open No. 58-114041, the exposure in the next step is carried out through one layer of toner that has adhered to the photoconductor in the previous development step, and the photoconductor under the toner layer is exposed. There is a method to perform multicolor recording by removing the electric charge from the body. In this case, the light transmittance of the toner used or the developed toner layer is a big problem. Even if the toner material itself has a high transmittance, if the toner is made into a single layer, light scattering components will increase, so the layer Transmittance is very low5
Partial variations in the amount of light transmission may occur due to page tearing or uneven distribution of toner adhesion amount.

On the other hand, in the electrostatic recording method, a method for realizing multicolor recording is to move the recording paper back and forth for each recording color onto an electrostatic latent image carrier such as electrostatic recording paper, and use a recording unit such as an electrostatic recording head. There is a method of sequentially repeating the process of forming an electrostatic latent image according to the image and developing it with toner of each color. In this case, 1 for each recorded color.
The disadvantage is that the process takes time and is difficult to speed up.

Purpose of the Invention The present invention overcomes the above-mentioned drawbacks, provides a multicolor recording method that allows for a simple device configuration and high speed, and that does not make the device complicated or large even when the number of colors to be recorded increases. It provides:

Structure of the Invention The present invention provides a step of forming two or more types of electrostatic latent images with different potentials corresponding to recorded colors on an electrostatic latent image carrier, and simultaneously forming at least two types of the electrostatic latent images. A developing step in which the developed amount is unsaturated with respect to the developable toner saturation amount for at least one type of six vanes among the electrostatic latent images, and then the electrostatic latent image is By including a step of developing with a toner of a different color, the structure is simplified and the speed is increased.

DESCRIPTION OF EMBODIMENTS The present invention will now be described in detail with reference to the drawings. Third
The figure shows an embodiment in which the present invention is applied to a two-color recording device using electrophotography, and FIG. 4 is a diagram illustrating the potential level of the process of the device of this embodiment.

In FIG. 3, reference numeral 17 denotes a recording drum having a photosensitive layer on its surface, the surface of which is uniformly positively charged by a charger 18 in a first step. The potential level on the surface of the recording drum 17 at this time is shown in FIG. 4aKV3. Next, in a second step, as the recording drum 17 rotates in the direction of the arrow, the surface is scanned by a laser beam 19 modulated in accordance with the image to be recorded, forming a latent image. The laser beam 19 is emitted from a laser oscillator 21 controlled by a power supply/modulation section 2o, passes through a bassine 22, is polarized by a rotating mirror 23, and is directed to a lens 2.
4 onto the recording drum 17.

At this time, the light intensity of the laser beam is modulated into two sizes depending on the position and color of the image to be recorded, so the color to be recorded is displayed on the recording drum after exposure as shown in Figure 4. Correspondingly v4. Holes 38 and 39 at the potential level v5 are created. In the next third step, the first developing section 26 develops with a first toner 36 colored, for example, magenta.

At this time, a bias voltage of Vbs is applied to the recording drum by the power supply 27 to the developing unit 26, and the first toner is positively charged in the developing unit 26. Also, the developing device 26
The amount of the first toner 36 supplied to the developing surface is -1=
The supply amount control member 28 limits the amount of toner supplied so that the amount is sufficiently smaller than the maximum amount of saturated toner that can be developed with the set bias voltage. Therefore, the potential level of the recording drum after being developed by the first developing section 25 is shown as shown in FIG. 4C. 40 and 40' indicate that the potential is increased due to the positively charged first toner 36 adhering to the holes at respective potential levels corresponding to the recorded colors. Since only a small amount of toner is attached to the potential level hole 39 compared to the saturated toner amount, a potential difference is generated between the potential level hole 38 and the potential level hole 38 . Furthermore, in the next fourth step, the second developing section 29 develops with a second toner colored, for example, cyan. At this time, a bias voltage of Vbs is applied to the developing device 3o by the power source 31 with respect to the recording drum, and the second toner is positively charged in the developing section 29. The potential level after development in the fourth step is
It will look like Figure d. In other words, the second toner does not adhere to the hole 38 because the potential level is high, but the second toner does adhere to the hole 38 because the potential level <39 is low.

The toner image formed on the recording drum 17 as described above is transferred onto the receiving paper 32 by the action of the charger 33 and fixed by the fixing section 36. A magenta image created by the first toner and a blue image created by the mixture of the first toner and the second toner are recorded on the receiving paper. As described above, in this embodiment, nine pages of two-color images can be recorded in a simple process of only one exposure.

Next, another example in which the present invention is applied to a three-color recording device will be described in the sixth section.
This will be explained with reference to FIGS. In this example, the third
Components having the same contents as those in the embodiment shown in the figures are given the same numerals, and a description thereof will be partially omitted. In FIG. 6, the potential level of the surface of the recording drum 17, whose surface was uniformly positively charged by the charger 18 in the first step, is shown in FIG. 6B. Similar to the embodiment shown in FIG. 3, the potential level on the surface of the recording drum 17 after being exposed in the second step is shown in FIG. Reference numerals 60 and 151 indicate holes with potential levels provided according to the colors to be recorded. In the third step, the surface of the recording drum is colored blue by the first developing section 26,
The first toner 47 is then developed with positively charged first toner 47 . Since the amount of the first toner 47 developed at this time is limited to be sufficiently smaller than the saturated toner amount as in the previous embodiment, the potential level after development is as shown in FIG. 6C.

63° and 63' indicate that the potential is increasing due to the adhesion of the first toner. Next, in a fourth step, a laser beam 42 is emitted for 10 pages corresponding to the signal to be newly recorded in the third color. As in the second step, the laser beam 42 is emitted from a laser oscillator 44 controlled by a power source/modulator 43, passes through a lens 44, is polarized by a rotating mirror 46, and is scanned through a lens 47 onto a recording drum 171-. The potential level on the surface of the recording drum 17 after passing through the fourth step is as shown in FIG. 6d. Holes 62 of potential levels to be recorded in the third color are provided by the laser beam 42. Next, in the fifth step, the second developing section 29 develops the toner with the second toner 49 colored red and positively charged, in the same manner as in the previous embodiment. At this time, since the potential of the holes 51 and 52 at the potential level shown in FIG. 6d is similarly low, the second toner 49 adheres to both of them and is developed as shown in FIG. 6e.

The toner image formed on the recording drum as described above is transferred onto the receiving paper 32 by the action of the charger 33 and fixed by the fixing section 36. A first toner 48 is placed on the receiving paper.
Thus, 11 pages of a blue image, a black image created by a mixture of the first toner 48 and the second toner 49, and a red image created only by the second toner 49 will be recorded. As described above, in this embodiment, a three-color image can be recorded with two exposures.

In addition, even when recording three or more colors, by repeating the above two-stage exposure and development with toner supply unsaturated, for example, by setting the potential level to two values, exposing three times and developing three times, six colors can be recorded. be able to.

The above is an example in which the present invention is applied to a two-color recording device using electrophotography. Next, see FIGS. 7 and 8 for an example of a two-color recording device when used in electrostatic recording. I will explain while doing so. Reference numeral 61 denotes electrostatic recording paper having an insulating layer on its surface, and is sent into the apparatus by feed rollers 62 and 63. Reference numeral 64 denotes a recording head (not shown) including a recording needle and a control electrode therein, which is connected to a power supply/control unit 64a and forms an electrostatic latent image on the electrostatic recording paper 61 in response to a signal sent therefrom. . 66°67
68 and 69 are developing units that develop magenta and cyan toners, respectively, and feeding rollers 68 and 69 that feed the electrostatic recording paper 61 after recording.

After the electrostatic recording paper 61 is charged by the recording medium 1, the surface potential of the electrostatic recording paper 61 becomes v6.corresponding to the recording color and image as shown in FIG. 8a. The potential level of v7 is 71.70 respectively.
A hole is provided with a potential level of . Next, the magenta color toner is developed by the developing section 65 to reach a potential level as shown in FIG.

73 and 73' indicate that the developed toner fills the potential hole and lowers the level. When developing magenta toner, the toner supply amount is limited, and the potential level hole 7
No. 1 is left unsaturated and moved on to the next step. Next, the cyan toner is developed by the developing section 67, and the unsaturated portions are developed and filled in as shown at 74 in FIG. 3C. As described above, a magenta image and a blue image, which is a mixture of magenta and cyan, are recorded on the electrostatic recording paper.

Effects of the Invention As is clear from the above explanation, the present invention exhibits the following excellent effects.

(1) In those using electrophotography, toner images of each color are superimposed on the recording drum, so high-speed recording is possible compared to a method that repeats the process from charging to transfer to a □13 vane for each color toner image. Also, in electrostatic recording, latent images are formed by moving the recording paper back and forth for each color.

Compared to methods that repeat the development process, high-speed recording is possible because latent images for multiple colors are formed in one recording.

(Threshold) Since a latent image for multiple colors is formed by one exposure or a latent image formation by the recording head, and a mixture of different color toners is used as one color, it is possible to generate multiple colors with a small number of exposures or recordings with the recording head and a small number of developing steps. Color recording can be obtained, and the device can be made simple and compact compared to the number of recorded colors.

(Because a latent image for multiple colors is formed by 311 exposures or recording by the recording head, there is little positional shift for each color compared to the number of recorded colors. Also, the rotation of the recording drum and the exposure timing to prevent misalignment are Alternatively, the necessary number of synchronized controls for recording paper feeding and recording timing can be omitted, simplifying the apparatus.

(4) Note that if a photoconductive layer provided on a conductive support is used as the electrostatic latent image carrier, the recording drive 14 base 7
- Since it is necessary to remove the charge on the photosensitive layer by exposing the toner layer developed in the previous process on the film, the problem of poor light transmittance of the toner used or the toner layer is eliminated, and the problem of poor light transmittance of the toner or toner layer is eliminated. The range of shapes that can be used is expanded. It also eliminates the problem of potential drop variations when exposing through a single layer of toner.

[Brief explanation of drawings]

Fig. 1 is a principle diagram of a conventional multicolor recording device, and Fig. 2 is a waveform diagram 1 for explaining the photosensitive layer potential level of the same device.
．． Fig. 3 is a principle diagram of a multicolor recording device implementing the multicolor recording method of the present invention, Fig. 4 is a waveform diagram for explaining the photosensitive layer potential level of the same device, and Fig. 6 is another example of the same. FIG. 6 is a waveform diagram for explaining the potential level of the photosensitive layer, FIG. 7 is a principle diagram of the same device according to another embodiment, and FIG.
The figure is a waveform diagram for explaining the potential level of the photosensitive layer. 18... Charger, 19... Laser beam, 21... Laser oscillator, 26...
First developing section, page 28... 16th supply amount control member, 29... second developing section,
32... Receiving paper, 34... Cleaning section, 3゛5... Fixing section, 42... Laser beam, 47... Laser Oscillator, 64...
...recording head, 65, 67...developing section. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 3 Figure 4 Surface Ki! Fig. 7 θ44! 8th cause

Claims (2)

[Claims] (1) A step of forming two or more types of electrostatic latent images with different potentials corresponding to recording colors on an electrostatic latent image carrier, and simultaneously developing at least two types of the electrostatic latent images, and a developing step in which the amount of development is unsaturated with respect to the saturation amount of toner that can be developed with respect to at least one of the electrostatic latent image forces, and then developing the electrostatic latent image with a toner of a different color from the toner. Multicolor recording method including process. (2) The multicolor recording method according to claim 1, wherein the electrostatic latent image carrier is an electrostatic recording material having an insulating layer provided on a conductive support. (q) The polychromatic σ method according to claim 1, wherein the electrostatic latent image carrier is an electrophotographic photoreceptor having a photoconductive layer provided on a conductive support.