JPS63192065A - Two-color copying method - 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] (Technical field) The present invention relates to a two-color copying method.

(Prior Art) A two-color copying method for copying a desired image part of a monochromatic document having a black image in chromatic A color and copying other image parts in black is to copy a desired image part on H's. A rectangle is specified with a digitizer, the corresponding part of the electrostatic latent image is erased with an LED array and visualized with black toner, and then, after forming an electrostatic latent image again, the latent image part outside the specified area is erased, A
A method is known in which images are visualized using colored toners and the visual images of each color are synthesized on transfer paper (Japanese Patent Laid-Open No. 59-67591).

However, this method requires expensive equipment for its implementation;
Further, there are other problems such as it is difficult to accurately specify the image area to be copied in color A, and a band of 2 to 3 mm is not copied at the boundary between each color image in a two-color copy image.

There is also a known method of printing a special two-color copy after filling in a desired part of a single-color document with a red highlighter pen (Japanese Patent Application Laid-Open No. 57-35870). There is a problem that it gets contaminated.

(Purpose) The present invention has been made in view of the above-mentioned circumstances, and its purpose is to do so without staining the manuscript itself.
Another object of the present invention is to provide a novel two-color copying method that can easily make two-color copies of a single-color original.

(composition) The present invention will be explained below.

The two-color copying method of the present invention is a method of copying a desired image portion of a monochromatic document having a black image on a white background in chromatic A color, and copying other image portions in black.

This method is performed as follows. First, copy a monochrome original onto a white transfer paper using A color toner to make a monochrome copy, and then fill in the image part that should be copied in black with transparent or colored ink on the monochrome copy, or Or cover it with a transparent or colored film to transfer the single color copy to the second
Use as manuscript.

Two-color copying using a composite photoreceptor having a laminated photoconductive layer sensitive to at least both A and B color light and a photoconductive layer sensitive to at least B color light, and black and A color toners. In the method of the present invention, a second original is created from the original original, and this second A two-color copying process is performed on the original. Various methods are already known for the two-color copying process using a composite photoreceptor and two-color toners, and these can be used as appropriate.

A detailed description will be given below with reference to the drawings.

For concreteness of explanation, chromatic color A is assumed to be red, and chromatic color B is assumed to be green.

In FIG. 1, numeral 0 indicates a monochrome original.

Original 0 has black images OA and OB on a white background, and a two-color copy image is obtained by copying image portion OA in red and image portion OB in black.

In this case, the procedure is to first make a monochrome copy of original 0 on white transfer paper using red toner, make a red monochrome copy CP (Fig. 1 (II)), and then copy the image part that should be copied in black. The red copy image OBR corresponding to OB is
As shown in Figure (III), this area is filled in with green ink (the area marked with broken lines) or covered with a transparent green film to form the second original 01.

Then, a two-color copying process is performed on this second original O1 to obtain a desired two-color ratio copy CPI (see FIG. 1 (TV
)).

(Embodiment) FIG. 2 is a schematic explanatory diagram showing only the essential parts of an example of an apparatus for carrying out the present invention. In FIG. 2, reference numeral 10 indicates a composite photoreceptor. is formed into a drum shape and is rotatable in the direction of the arrow. As shown in FIG. 5, the photoreceptor 10 has a conductive base 10B (aluminum drum).
photoconductive layer on the circumferential surface.

It is formed by laminating a medium-zero layer M and a photoconductive layer U, and is manufactured as follows. That is, a photoconductive layer is formed by vacuum evaporation on an aluminum drum, overcoated with a phenol resin to a thickness of 0.5 to 1.5 tons using a dipping method to form an intermediate layer M, and further coated with thiapyrylium salt and polycarbonate. A photoconductive layer U was obtained by overcoating a eutectic OPC composed of a eutectic and a triphenylmethane derivative to a thickness of 22 mm using a dipping method. The photoconductive layer U has a spectral sensitivity as shown by curves 4-1 and 4-2 in FIG. 4, respectively. The sensitivity of the leading @ layer is panchromatic, but the photoconductive layer U
absorbs red light and does not transmit it, so the photoconductive ML in the photoreceptor has no sensitivity to red light.

Consequently, the photoconductive layer is sensitive to green light (color B) and blue light, and the photoconductive layer U is sensitive to both green light and red light (color A). Note that the intermediate layer M is for carrier trapping.

Now, in order to perform two-color copying, in Fig. 2, the photoreceptor 1
0 while rotating the charger 12 with a lamp,
While uniformly irradiating the photoreceptor with red light, the photoreceptor is charged to +700V with a discharge voltage of +5.5KV.

This state is shown in FIG. 3(1), and the charging potential appears as the charging potential of the photoconductive layer. Next, monochrome original 0 (first
When imagewise exposure is performed using the light image shown in FIG. 3 (I)), the charged state of the photoconductive layer is dissolved in the exposed area, and an electrostatic latent image is formed (FIG. 3 (II)).

When the latent image thus obtained is developed with red toner by the developing device 18, as shown in FIG. 3 (III),
Since a visible image is obtained using the red toner TR, this is transferred to white transfer paper. That is, as shown in FIG. 2, the transfer paper SO is delivered from the cassette I9 by the paper distribution roller 20, the registration roller 24 sends it to the transfer section, and the transfer separator 26 transfers the red visible image and separates the transfer paper. The image is separated from the photoreceptor, the visible image is fixed by the fixing device 28, and the image is discharged from the device. In this way, a red monochrome copy CP (FIG. 1 (II)) is obtained from M document 0. Note that at this time, the conveyance path 22 on which the transfer paper SO is conveyed is
It is called a conveyance path.

In the monochrome copy CP thus obtained, the image portion to be copied in black is filled with green ink, thereby obtaining the second original 01. Note that during this time, the photoreceptor 10 after the visible image has been transferred is cleaned by the cleaner 30.

Therefore, next, a two-color copying process is performed using the second original 01. That is, while rotating the photoreceptor 10 in the direction of the arrow in FIG. 2 and irradiating red light with the lamp-equipped charger 12, the photoconductive layer was increased by +2 at a discharge voltage of +7.0V.
000V1. - Charging Figure 3 (IV)), and further,
Charging is performed in the dark using a charger 14 at a discharge voltage of -4.9 KV, and as shown in FIG. 3ff), the photoconductive layer is charged in the opposite direction. At this time, the photoconductive layer, U
The charging potentials are ÷700V and -800V, respectively, and the photoreceptor surface potential is -100V.

Subsequently, image exposure is performed by irradiating the second original 01 with a light image.

FIG. 7 schematically shows the second original. Code OAR
, OBR is the black image OA in the original O (Fig. 1),
A red copy image corresponding to OB is shown, and the symbol G indicates green ink that filled in the image portion including the red copy image OBR. The ink G has a spectral transmittance of 5-1 shown in FIG. 6, and the red toner TR constituting the red copy image has a spectral reflectance of 5-2 shown in FIG.

Therefore, when the second original 01 is irradiated with white light W, as shown in FIG. However, in the red copy image OBR, the ink G and toner TR absorb most of the light, so the red copy image OBR filled with ink G becomes black. Since both the photoconductive layer and U are sensitive to green light, the charged state of the photoconductive layer is lower in the background area of the second document, the area corresponding to 0 ink, as shown in FIG. 3 (VI). , U
Both are canceled and the photoreceptor surface potential is approximately Ov at these parts.
becomes. Further, in the region corresponding to the red copy image OAH, only the photoconductive layer U is no longer charged, and the surface potential of the photoreceptor becomes approximately +600 cm at this region. Furthermore, the surface potential of the photoreceptor at the part corresponding to the red copy image OBR is 11
Maintain 00■.

Therefore, when the electrostatic latent image thus formed on the photoreceptor 10 is developed with negatively charged red toner in the developing device 18 shown in FIG. 2, the toner T as shown in FIG.
Since a red visible image is obtained by R, this is transferred to the transfer paper SO in the same manner as described above, and after being fixed, it is sent to the stocker 33 via the second conveyance path 32B in FIG. 2 and stocked. After cleaning the photoreceptor using the cleaner 30, the photoconductive layer U is then heated to 1700 by using the charger 14 at a discharge voltage of -5.5 KV.
3 (IIX) The photoconductive layer has a rectifying property for positive carriers), the photoconductive layer U is sensitive to both red and green light. Therefore, by this image exposure, Fig. 3 (IX)
As shown in , an electrostatic latent image corresponding only to the red copy image OBH is formed. Therefore, this electrostatic latent image is developed with positively charged black toner by the developing device 16 shown in FIG. 2, to obtain a visible image using black toner TB as shown in FIG. 3(X).

On the other hand, in FIG. 2, the material is stocked in the stocker 33 in the previous process. The transfer paper SO, on which the red visible image has already been fixed, is sent to the second conveyance path 32A by the roller 31, and is recursively conveyed to the transfer section by the same conveyance path 32A, so that the black visible image is converted into a red visible image. By positioning, transferring, and fixing, a desired two-color copy image can be obtained. The photoreceptor 10 after the black visible image has been transferred is cleaned by a cleaner 30.

FIG. 8(I) shows the change in the surface potential of the photoreceptor in the steps explained with reference to FIG. 3 (m to ■■).

Further, FIG. 8 (II) shows the changes in the photoreceptor surface potential in the steps of FIGS. 3 (IIX) and (IX).

In the above-described embodiment, the two-color copying process is a so-called sequential method in which electrostatic latent images to be developed with the toners TR and TB of each color are sequentially formed with a temporal shift.
A so-called simultaneous method may be used in which electrostatic latent images developed with TB are coexisting as distributions of photoreceptor surface potentials of opposite polarity.

It goes without saying that a green transparent film may be superimposed on the image portion of the monochromatic copy CP of the red visible image to be copied in black to form the second document.

(Effects) As described above, according to the present invention, a novel two-color copying method can be provided. In this method, a monochrome copy of the original is used to create the second original, so the original is not smeared during two-color copying. Furthermore, any image portion of a monochromatic black image can be easily and reliably copied in chromatic colors, and no image is left out.

Further, the two-color ratio copying process can be carried out by using a conventionally known two-color copying apparatus with appropriate modifications.

In FIG. 2, the reference numeral 32C indicates a conveyance path for double-sided copying.

[Brief explanation of the drawing]

Fig. 1 is a diagram for explaining the details of the present invention; Fig. 2 is an explanatory diagram schematically showing only the essential parts of an example of an apparatus for carrying out the invention; Fig. 3 is a diagram for explaining the details of the present invention; Figures 4 and 5 are diagrams for explaining the photoreceptor in the apparatus of Figure 2, and Figures 6 to 8 are diagrams for explaining the above embodiment. This is a diagram for 016. Monochrome manuscript with black image, cp, , . Monochrome copy of original O, 01. , ,Second manuscript, CPI
, . , two-color copying (Figure 2/Figure 84 Figure 5 Figure G Figure 7 Figure 8 (T-)

Claims (1)

[Scope of Claims] A method for copying a desired image part of a monochrome original having a black image in chromatic A color and other image parts in black, the method comprising: first copying the monochrome original with A color toner; Make a single-color copy by copying it in a single color onto white transfer paper, and then fill in the image part that should be copied in black with transparent B-color ink or cover it with a transparent B-color film on the above-mentioned single-color copy to make a single-color copy. Uses a composite photoreceptor having a laminated photoconductive layer sensitive to at least both A and B color light and a photoconductive layer sensitive to at least B color light, and black and A color toners as a second original. 2
A color copying process is performed on the second original to obtain a two-color copy image of black and A color,
Two-color copying method.