JPS606955A - Recording method of color image - Google Patents

Abstract

PURPOSE:To perform high-efficiency color image recording without any shift in color by using a photosensitive body which has at least a transparent base, a filter layer, a transparent electrode layer, and two photoconductive layers. CONSTITUTION:The photosensitive body 10 moves from left to right, and exposed to an image after primary electrostatic charging and secondary electrostatic charging by chargers 22 and 23. A lamp 20 exposes the photosensitive body 10 through a slit. The photosensitive body is irradiated with light from the lamp 20 and developed by a developing device 25 with cyan toner. Similarly, it is developed by a developing device 28 with magenta toner. Further, the photosensitive body is developed by a developing device 31 with yellow toner. The obtained color visible image is transferred to transfer paper S by a charger 33 for transfer, and fixed by a fixing device. Thus, color image recording is carried out by the single-time image exposure, so the efficiency is improved and the transfer is completed at a time, so that no color shift is caused.

Description

[Detailed description of the invention] (Technical field) This invention relates to a color bimodal recording method, in detail.

The present invention relates to a color image recording method using a photoconductive photoreceptor.

(Prior Art) As a method for recording both color peaks using a photoconductive photoreceptor, a method using the Carlson process is conventionally known.

In other words, after charging the photoreceptor, an image is exposed using a color #J light beam separated by a red filter to form an electrostatic latent image corresponding to both peaks of the color component. The latent image is developed with cyan toner, and the resulting cyan visible image is transferred onto transfer paper. Next, the same process is carried out on one color image separated by a blue filter, and the resulting electrostatic latent image is bound with yellow toner, and the resulting visible yellow color is transferred onto the transfer paper. , transferred over the cyan visible image. Further, an electrostatic latent image corresponding to the color separation color image group is formed using a green filter, and this image is developed with a magenta toner, and the resulting magenta visible image is transferred onto the transfer paper. Thus.

Both color peaks are reproduced by visible images of the three primary colors transferred onto the same transfer paper.

In this color image recording method, color separation is performed using three primary color filters with both color peaks, but for each color separation,
Since the process from charging the photoreceptor to transferring the visible image is repeated, it takes a long time to obtain one color recorded image.

In addition, since each of the three primary colors is transferred separately to the same transfer paper, the relative positioning of the transferred visible image and the transfer paper must be performed accurately for each transfer. However, due to mechanical errors, perfect alignment is impossible, and the color difference between the two peaks of the resulting color record is misaligned.
Occasionally, a color stain n that is clearly visible to the naked eye may occur.

(Purpose) Therefore, an object of the present invention is to provide a novel color image recording method that can record color images with high efficiency and does not cause color stains on both sides of the color recording. shall be.

(composition) The present invention will be explained below.

In practicing the invention, a special composite photoreceptor is used.

In other words, the photoreceptor used in carrying out the present invention is as follows.

It has at least a transparent support, a filter layer, a transparent electrode layer, and two photoconductive layers.

The filter layer is formed by regularly arranging minute filters of 3Jf colors α, β, and γ in a mosaic pattern, and is directly provided on a transparent support.

A transparent electrode layer is provided on the filter layer.

The two photoconductive layers are laminated on the transparent electrode layer, but they differ from each other in 1 spectral sensitivity or absolute sensitivity.

Note that the photoreceptor includes at least a transparent support, a filter layer, a transparent electrode layer, and two photoconductive layers. This is because, for example, an intermediate layer or a filter layer may be further interposed between two photoconductive layers.

In such a photoreceptor, the two photoconductive layers θ are first charged in opposite directions.

Subsequently, image exposure is performed by irradiating light images of both color peaks, and in this image exposure, the light images are irradiated from the side of the transparent support of the photoreceptor.

Next, the photoreceptor is uniformly exposed from the side of the transparent support, and the light of this uniform exposure is.

Light transmitted through the α color filter of the filter layer is used to form a first electrostatic potential corresponding to the ξ color component image by making one of the photoconductive layers primarily conductive.

Here, the ξ color is a complementary color to the α color.

The first electrostatic latent image thus formed is developed with eight color toners.

Next, the light that passes through the β color filter in the filter layer,
Uniform irradiation of the photoreceptor is also carried out from the side of the transparent support to form a second electrostatic latent image corresponding to both peaks of the η color component in the same manner as the first electrostatic latent image. The η color is a complementary color to the β color.

At the same time as forming this second electrostatic a@, or at this time.
Before and after, uniform irradiation with light that passes through the α color filter is performed to remove the first electrostatic latent 1 that was previously formed and the current □□□
The image is weakened to the extent that it does not interfere with the visual image of the second electrostatic latent image. Then, a visual image is created using the second electrostatic latent color toner.

Further, the photoreceptor is uniformly exposed from the side of the transparent support with light transmitted through the γ color filter of the filter layer, thereby forming a third electrostatic latent iron corresponding to both peaks of the ζ color component. Also, β
Uniform illumination by light transmitted through the color filter weakens the second electrostatic latent image so that development of the third electrostatic latent image is not hindered.

And this third electrostatic potential? Illustrated with ζ color toner.

In this way, a color image corresponding to both color peaks is obtained on the photoreceptor.

All uniform irradiation of the photoreceptor was performed from the transparent support side, and all development was performed from the photoconductive layer σ) side.
By doing this, the color visible layer is formed on the surface of the photoconductive layer.

Then, by transferring and fixing this color visible image onto a recording medium such as paper, a desired color recording group is obtained.

Description will be given below with reference to the drawings. For concreteness of explanation, the three primary colors α, β, and γ are assumed to be red, green, and blue, respectively. Then, these f's complementary colors ξ and η.

ζ is cyan, magenta, and yellow in terms of the wick.

FIG. 1 shows, as an explanatory diagram, one example of a photoreceptor used in carrying out the present invention.

The photoreceptor designated by reference numeral 1 has a filter layer 12. on a transparent support tJ. A transparent electrode layer 13, a photoconductive layer, and U are laminated in this order.

As the transparent support 11, a glass plate, plastic, transparent resin film, etc. can be used.

The filter layer 12 is made up of fine filters of three primary colors, red, green, and blue, arranged in a regular mosaic pattern. Each section of the filter layer 12 has an individual microscopic filter, and the symbols JG and B written in each section indicate the color of each filter to be transmitted. That is, R
is red, G is green, and B is blue. Below, this code JG.

BT& serves as the code of each filter. That is, red filter R9, green filter G, and blue filter B are used in sequence.

The filter layer 12 +i can be formed on the transparent support 11 using the same technique used to make filters for VTR cameras.

The smaller the dimensions of each color filter R, G, B,
The resulting color recording has good resolution and image quality, but considering the particle size of each color toner to be developed as an electrostatic latent image, the dimensions of each color filter R9G and B are 10μ
Approx. m square is appropriate.

In this example, the dimensions of each color filter R, , G, B are as follows.

Let it be a square with negative sides of 10 μm. It has mosaic filters of each color. This filter layer 12 has a layer thickness of 1 μm or less. In addition, in this example,
Each color filter (R, G, B) has a spectral transmittance characteristic as shown by curve 3-1.3-2.3-3 in FIG.

The transparent electrode layer 13 formed on this filter layer 12 has a thickness of 1 μm or less, and is formed by a dipping method or a vapor deposition method depending on the material of the filler layer 12.

The two photoconductive layers L and U have different spectral sensitivities from each other.

In this example, it is assumed that the photoconductive layer has a spectral sensitivity as indicated by the chain line 2-1 in FIG. Photoconductive materials with such spectral sensitivity include organic photoconductors, so-called OPs.
There are C etc. Further, it is assumed that the photoconductor 16 tJ has a spectral sensitivity as shown by curve 2-2 in FIG. Examples of photoconductive materials having such spectral sensitivity include zinc oxide-resin dispersion systems.・As mentioned earlier, there is an intermediate layer (carrier trap layer) between the photoconductive layers U, L, and σ.
S may also include a filter layer.

Further, in the photoreceptor 1 shown in this example, the photoconductive layer has photosensitivity to positive charging, and the photoconductive layer U has photosensitivity to negative charging. Of course, the reverse may be used, or both charging properties may be used.

Further, there is a rectifying property between the transparent electrode layer 13 and the photoconductive layer, so that holes can be easily injected from the transparent electrode layer 13 to the photoconductive layer. In order to achieve such rectification, a hole injection layer may be formed as a part of the electrode layer between the transparent electrode layer J3 and the photoconductive layer.

The thickness of each photoconductive layer and U may be 10 to 10 .mu.m, but according to experiments, the best color image (illustration) was obtained when the thickness was 20 .mu.m and 8 degrees.

Now, each step of the color image recording method will be explained below.

First, FIG. 4 shows the process of charging the photoconductive layers U and L7 of the photoreceptor 1 in opposite directions. Refer to and explain.

From the side of the photoconductive layer U in the dark relative to the photoreceptor 1.

Uniform charging with negative polarity is performed. Due to this uniform charging, the surface of the light guide m layer U is uniformly negatively charged (FIG. 4(I)).

However, since there is a rectifying property between the transparent electrode layer 13 and the photoconductive layer, the photoconductive layer is separated from the transparent electrode layer 13 by the action of the electric field formed by the negative charges that charge the surface of the photoconductive layer U. Then, holes are injected, and the injected holes move through the photoconductive layer Lfi7i and are trapped at the interface between the photoconductive layer and U. This state is the state shown in FIG. 4(I). This charging process is called primary charging. In addition,
If the rectifying property is not present, the difference in spectral sensitivity between the photoconductive layers L and tJ is utilized, for example, at the same time as the primary charging, the photoconductor IK is charged with a voltage of 750 or more, for example, from the side of the photoconductive layer U. Wavelength of light? By irradiating and turning only the photoconductive layer into a conductor, the state shown in FIG. 4(I) can be achieved.

Now, the state shown in FIG. 4(I) is that the photoconductive layer U 7
This is a state in which an electric double layer is formed between the two layers.

Therefore, this state is considered to be a capacitor, and the photoconductive layer U is said to be charged.

Next, in the dark, the polarity opposite to the primary charge, that is,
Performs positive secondary charging.

As the secondary charging progresses, the negative charges on the photoconductive layer U gradually increase in phase number n. Then, according to the method, the balance between the positive charge at the interface between the photoconductive layers L and U and the negative charge on the photoconductive T5 layer U is disrupted. This is induced at the interface between the optical 2M and the optical 2M-tun layers, and a state as shown in FIG. 4 (TT) is realized. In this state, an electric double layer is formed through the photoconductive layer and each side of U and L. However, the directions of the dipole moment vectors in each electric double layer are opposite to each other. Therefore, we call this state @ photoconductive j*L
.

This is said to be a state in which U are charged in opposite directions.

Since the transparent electrode layer 13 is grounded, the surface potential of the surface of the photoreceptor 10, that is, the surface potential of the photoconductive layer U is the sum of the charged potentials of the photoconductive layer U. Here, it is assumed that the photoconductive layer is charged to +10 nOV, the photoconductive layer U is charged to 11000 V, and the photoreceptor surface potential is O.

Next, each of the following steps will be explained with reference to FIG.

In the photoconductive layer, U are charged in opposite directions to each other and the photoreceptor 1
On the other hand, as shown in FIG. 5(I), the transparent support 11
Image exposure is performed by irradiating color image 0 with heat from the side.

Color image 1 elephant O is black image BL, white face groan W, cyan image CI, magenta picture iron MA, yellow image YE, blush @R
E, Recording GR, Blue image BLUf2 (supposed to have. Then, with this image exposure, the photoreceptor parts corresponding to each color image are exposed to white light W and cyan light LC, respectively)
, magenta color light LM, (yellow color light LY.

The anus, which is irradiated by the red light LR, the green light LG, and the blue light LB, and the parts corresponding to the black+tii group are not irradiated with light.

Note that this one-image exposure is performed through a band pass filter (not shown) that transmits light of 400 to 70011111. By this image exposure, as shown in FIG.
) is formed.

That is, since the portion corresponding to the black picture iron BLK is not irradiated with light, no change occurs. The region corresponding to the self-portrait W is illuminated with white light LW.

The white light LW has blue, red, and green components as n −'Hn
, .

Blue filter B, red filter R, i filter G)k
It passes through the photoconductive layer and acts on the U. Light guide i five layers,
Since both U have panchromatic spectral sensitivities (Figure 2), each photoconductivity/i#L and U are both made into conductors.
The charged state is eliminated, and the surface potential of the photoreceptor becomes O at this location.

The region corresponding to the cyan acquaintance is irradiated with the cyan light LC. Since the cyan light LC contains green light and blue light as components, these components pass through the green filter G and the blue filter B7, respectively.

Solve the state of charge in the photoconductive layer U/l! ! do. The same thing occurs in the parts rq corresponding to other color images,
As a result, a charge distribution as shown in FIG. 5(I) is formed on the photoreceptor 1.

With this double exposure, a photoconductive layer is formed by light irradiation.

The surface potential of the part where the charged state of U is released becomes O, but in other parts, the photoreceptor surface potential as the sum of the charged potentials of each photoconductive layer becomes O, despite the presence of charge. Therefore, in the 5121st (I) state, the surface potential of the photoreceptor is 0 everywhere, even though the charge distribution is non-uniform as shown in the figure.

Next, from the side of the transparent support 11, the dragon light L1 with a wavelength of 730
irradiate uniformly. Referring to Figure 3, as is clear, the light of wavelength 730 is the spectral transmittance characteristic 3-1.
It is transmitted only through the red filter 11 having a red filter. Also, as is clear from FIG. 2.

Is it possible to solve the charge state by turning only the photoconductive layer into a conductor? Do P4. In this way, in the black image corresponding area, cyan image (*'R corresponding area, recording iron corresponding area, and blue image (8) corresponding area), the charged state of the photoconductive layer is resolved in the area directly above the red filter R. Then, since the surface potential of the photoreceptor at these f parts becomes the charged potential of the photoconductive layer U, a negative surface potential appears at these n parts.This negative potential is theoretically Actually, it should be -100OV,
In reality, dark decay etc. exist, so -700 to -8
The potential is about 00V.

In this way, the photoreceptor sections corresponding to the black images (@BL, cyan image CI, Rokuryoho GR, and blue image BLU) are set.

The surface potential of negative polarity is shown below.

This surface potential distribution is called a first electrostatic latent image.

By the way, there are 777 primary color components that are commonly included in the four colors of black in a black image, cyan in a familiar cyan image, green in a recorded image, and blue in a blue image. Therefore, this first electrostatic latent image corresponds to both peaks of the cyan color component of the color image @O.

Therefore, this first electrostatic latent image is developed with positively charged cyan toner TC'' (FIG. 5 (■)).

Next, this time, the light L24 with a wavelength of 76011+m 2 is irradiated (FIG. 5 (■)). This light L2 passes only through the green filter q, as is clear from FIG.
As is clear from FIG. 2, only the photoconductive layer is made conductive. By uniformly irradiating this light L2, an electrostatic latent image corresponding to both peaks of the magenta color component, which is a complementary color to green, is obtained as a negative surface potential distribution.

Therefore, this electrostatic latent image is called a second electrostatic latent image, and is developed with positive polarity magenta toner TM (Fig. 5 (V)). First electrostatic latent 1
Even though the elephant has not been developed yet.

It has a strong electric charge RY, and therefore, if development with magenta color toner TM is performed as it is, the first electrostatic latent image will be developed overlapping the cyan color toner TC.

Therefore, before development with magenta toner TM is performed, red light LR'r is uniformly irradiated from the transparent support 11 side to weaken the first electrostatic latent image. In the figure, it appears as if the first electrostatic latent image has been completely erased.

However, in reality, a voltage of about -100V (Uk) may be left. In this way, when cleaning the surface with magenta toner, the image with cyan toner will not be disturbed. 7 Note that this uniform irradiation of the red light LR may be performed simultaneously with the uniform irradiation of the light L2, or may be performed before or after the uniform irradiation of the light L2.

Subsequently, as shown in FIG. 5 (VI), the transparent support 1
Light is emitted from the 1 side for uniform irradiation.

The wavelength of this light is 370 mm, and as is clear from Fig. 3, it passes through only the blue filter B, and as is clear from Fig. 2, only the photoconductive layer is made into a conductive body. . Therefore, it is clear from the above explanation that the third electrostatic latent image of negative polarity formed by the uniform irradiation of this light corresponds to the yellow image component of color image 0. Probably.

Therefore, the second electrostatic latent image is weakened by uniform irradiation with green light LG, and the third electrostatic latent image is developed with positively charged yellow toner TY (FIG. 5 (Vlf)).

In this way, a color visible image corresponding to the color image o is obtained on the photoreceptor 1. All that is left to do is to transfer this visible image onto a recording medium such as plain paper and fix it to obtain the desired color. A recorded image is obtained.

It should be noted that the finer the particle size of the toners TC, TM, and TY used, the better, but in the case of dry development, approximately 5 μm is appropriate.

By the way, as is clear from FIG. 5 (■), each color toner making up the color visible group is placed on the photoreceptor 1? The area covered is small compared to the area of the original color image. Therefore,
The resulting color recorded image has both chromatic color peaks [the image density tends to be low].

To solve this problem, each color toner can be mixed with several grams of sodium bicarbonate, so that when the visible image is fixed, the toner expands due to thermal foaming, increasing the area it covers the recording medium. .

FIG. 6 schematically shows only the essential parts of an example of an apparatus for carrying out the present invention. To explain according to the example explained with reference to FIGS. 4 and 5, the photoreceptor 10 is formed into a belt shape,
It is conveyed from the left to the right in the drawing via a pulley 32, receives primary and secondary charging by chargers 22 and 23, and then undergoes image exposure.

f, that is, the translucent color original Oγ is the lamp 2
0, the illumination scan is performed fL, and at the same time, the 1 nons 21 moves in the direction of the arrow, thereby exposing the photoreceptor 1'f slit.

Thereafter, the photoreceptor 1 is irradiated with light IJl by a lamp 24 and developed with cyan toner by a developing device 25. Subsequently, the lamp 26 uniformly irradiates the light L2, the lamp 27 uniformly irradiates the red light, and the +ur mount #2
8, the image is developed with magenta toner.

Furthermore, the lamps 29 and 30 cause light L3, green light LG
The toner is uniformly irradiated with yellow toner and developed by the developing device 31 using yellow toner.

The thus obtained color visible image is transferred onto the transfer paper S by the transfer charger 133.

Thereafter, the image is fixed onto the transfer paper S by a fixing device (not shown).

Note that the photoreceptor is formed into a drum shape and subjected to image exposure.

It may also be done from inside the drum.

(Effects) As described above, according to the present invention, a novel method for illustrating color images can be provided. In this method, color images can be recorded with a single image exposure, so that color images can be recorded with high efficiency. In addition, since the color visible image is formed on the photoreceptor and transferred at once, in the resulting color recorded image.

No discoloration occurs.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the photoreceptor used in carrying out the present invention, FIGS. 2 to 5 are diagrams for explaining the present invention, and FIG. 6 is a diagram for explaining the present invention. FIG. 2 is an explanatory diagram schematically showing only the main parts of an example of the device. DESCRIPTION OF SYMBOLS 1... Photoreceptor, 11... Transparent support, 12...
Filter layer, 13...Transparent electrode layer, L, U.
... Photoconductive N, TC, 'I'M, TY-... Toner

Claims (1)

[Claims] A filter layer consisting of minute filters of three primary colors α, β, and γ regularly arranged in a mosaic pattern is provided on a transparent support, and a transparent electrode layer is provided on this filter layer. Further, in a photoreceptor, in which at least two photoconducting layers having different spectral sensitivities or absolute sensitivities are provided on the transparent electrode layer, the two photoconductive layers are oriented in opposite directions. After charging, a light image of a color image is irradiated from the side of the transparent support to perform double exposure. Next, the α color filter of the above filter layer? By uniformly exposing one side of the photoconductive layer to a conductive layer with transmitted light, both peaks of the ξ color component (ξ color is the complementary color of α color) are produced.
A first electrostatic reservoir corresponding to K is formed, and this first electrostatic latent image is bounded with eight color toners. Next, uniform exposure is performed with light that passes through the β color filter in the filter layer, and by making one side of the photoconductive layer mainly conductive, it supports both peaks of the η color component (η color is the complementary color of β color). At the same time or in succession to this electrostatic latent image forming step, a second electrostatic latent image is formed, and light passing through an α-color filter is uniformly irradiated to form a second electrostatic latent image. The second electrostatic latent image is weakened to the extent that it does not interfere with the development of the second electrostatic latent image, and then the second electrostatic latent image is developed with four-color toner, and then uniformly exposed with light that passes through the seven-color filter of the filter layer. By making one side of the photoconductive layer mainly conductive, a third electrostatic latent group corresponding to the ζ color component image (ζ color is the complementary color of γ color) is formed, and this electrostatic latent image Simultaneously with or in succession to the forming step, the second latent image is weakened to the extent that the development of the third electrostatic latent image is not hindered by uniformly irradiating light that passes through the β color filter. Subsequently, a third electrostatic latent image w 3 is created using the ζ color toner.
A color image recording method characterized by obtaining a color visible edge on the surface of a photoconductive layer side of a photoreceptor by displaying the image, and transferring and fixing this color image onto a recording medium.