JP4132024B2 - Standard density original printing method for color image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a standard density original printing method for a color image forming apparatus such as a color printer, a color FAX, or a color copying machine.
[0002]
[Prior art]
In a conventional color image forming apparatus, as a method of correcting the color density for each color (each developing device), a standard density original (calibration page) determined in advance is printed, and the printed standard density original and a specified color are printed. Density correction was performed by comparing the density with a density sample (reference card) and inputting a density correction value from a color image forming apparatus or an input device connected to the color image forming apparatus when the density differs from the specified density. .
[0003]
Alternatively, as a printing quality evaluation method for a high-definition color image forming apparatus, there is a method of printing an intermediate density with each color pattern. For example, as described in Japanese Patent Application Laid-Open No. 5-20437, the density halftone pattern 1 of the print density, the line pattern 2 in which the line-to-line density formed by a plurality of lines gradually decreases, and the different density A method is disclosed in which at least one of the density gradation patterns 3 in which regions are drawn in stages is printed with an indicated color, and the printed pattern is evaluated.
[0004]
[Problems to be solved by the invention]
However, since the conventional method prints a standard density original or pattern with each color (yellow, magenta, cyan, black) in a single color, it is quite difficult to evaluate the difference when comparing with the density of the color density sample. There was a problem of requiring skill. Further, since yellow itself is originally a light color, there is a problem that it is difficult to recognize gradation from a printed standard density original or pattern.
[0005]
[Means for Solving the Problems]
The present invention has been made in view of the above problems, and in a standard density original printing method of a color image forming apparatus that includes a plurality of developing units and can print a standard density original for comparison with a color density sample. Printing is performed in a state where a color mixture portion by two or more developing devices is formed on a standard density original, and the color mixture portion is formed by overlapping a plurality of portions having different densities of concentric circles of each color, and the concentric circles of each color are The standard density original printing method of the color image forming apparatus is characterized in that the color is expressed so as to change from the outer periphery to the inner periphery or from the inner periphery to the outer periphery.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing each configuration of the photosensitive drum unit. An electrostatic latent image is formed on the photosensitive drum 1 around the photosensitive drum 1 by charging means 2 for uniformly charging the surface of the photosensitive drum. Exposure means 3 for developing, developing means 4 for developing toner on the electrostatic latent image, primary transfer means 5 for transferring the developed image on the photosensitive drum 1 onto the intermediate transfer belt 10, transfer on the photosensitive drum 1 A cleaning blade 6 that cleans the remaining toner and a neutralizing unit 7 that neutralizes the surface of the photosensitive drum 1 are provided.
[0007]
FIG. 2 is a diagram showing a tandem type color printer in which the four photosensitive drum units shown in FIG. 1 are arranged in parallel. Each color of black (K), cyan (C), magenta (M), and yellow (Y) is shown. The photosensitive drums 1a to 1d for forming the toner images for each are arranged in the traveling direction of the intermediate transfer belt 10, and the toner images are formed on the photosensitive drums 1a to 1d in synchronization with the feeding of the intermediate transfer belt 10. Thus, the image is primarily transferred onto the intermediate transfer belt 10, and then transferred to the recording medium P by the secondary transfer roller 14 and fixed by the fixing device 16. In FIG. 2, reference numerals 4a to 4d denote developments in the developing means for developing toners for the respective colors of black (K), cyan (C), magenta (M), and yellow (Y) on the photosensitive drums 1a to 1d. Roller 11, driving roller for intermediate transfer belt 10, 12 tension roller, 13 backup roller provided opposite to secondary transfer roller 14, and 15 elastic for cleaning secondary transfer residual toner on intermediate transfer belt 10 Body blade. The other configuration shown in FIG. 2 is the same as the configuration shown in FIG.
[0008]
The primary transfer means 5 presses against the photosensitive drum 1 with the intermediate transfer belt 10 sandwiched therebetween, applies a predetermined DC voltage to perform primary transfer, and the secondary transfer roller 14 transfers the recording medium and the intermediate transfer belt 10 to each other. The secondary transfer is performed by applying pressure to a backup roller 13 as a counter electrode and applying a predetermined DC voltage. Further, the elastic blade 15 for cleaning the residual toner on the intermediate transfer belt 10 after the secondary transfer is pressed against the portion supported by the tension roller 12 in a counter manner with respect to the rotation direction of the intermediate transfer belt 10. is doing.
[0009]
The present invention is characterized in that a standard density original as shown in FIG. 3 is printed by such a color image forming apparatus such as a color printer. In FIG. 3, 21 is a standard density original, 22 is a standard density original title, 23 is a cyan density gradation concentric circle, 24 is a magenta density gradation concentric circle, 25 is a yellow density gradation concentric circle, and 26 is a black density gradation. , 27 is a cyan / magenta mixed color portion, 28 is a cyan / yellow mixed color portion, and 29 is a magenta / yellow mixed color portion.
[0010]
Here, the print pattern of the cyan density gradation concentric circle part 23, the magenta density gradation concentric circle part 24, and the yellow density gradation concentric circle part 25 has a darker color as it changes from the outer periphery to the inner periphery (or from the inner periphery to the outer periphery). It is preferable to constitute as shown. In this configuration, when concentric circles are set to density gradations for each color, the density gradations that can be expressed by the color image forming apparatus are set to the same or can be recognized by the user. It can be used for the purpose of density adjustment.
[0011]
The present invention is characterized in that a mixed color portion (cyan / magenta mixed color portion 27) is formed by overlapping each of a cyan density gradation concentric circle portion 23, a magenta density gradation concentric circle portion 24, and a yellow density gradation concentric circle portion 25. The cyan / yellow mixed color portion 28 and the magenta / yellow mixed color portion 29) are easier to see than a single yellow color because the print pattern constitutes a color gradation.
[0012]
The cyan / magenta mixed color portion 27 becomes a color close to purple, and the color arrangement changes sequentially depending on whether the purple is close to cyan or magenta. The cyan / yellow mixed color portion 28 has a color close to green, and the color arrangement changes sequentially depending on whether the green is close to cyan or yellow. The magenta / yellow mixed color portion 29 has a color close to pink, and the color arrangement changes sequentially depending on whether the pink is close to magenta or yellow. By forming such a color mixture portion, not only can it be used for the purpose of density adjustment, but also the degree of color misregistration can be confirmed by the overlapping portion of each circle.
[0013]
Note that black is expressed in black even if it is mixed with other colors, so the black density gradation portion 26 is formed in a region that does not mix with other colors, and a black density gradation printed pattern is formed. Is preferred.
[0014]
In this embodiment, each color is concentrically arranged so as to represent a darker color as it transitions from the outer periphery to the inner periphery (or from the inner periphery to the outer periphery), and a part of the circle is overlapped so that the color mixture portion is overlapped. By forming, the mixed color portion of three colors is efficiently formed, but the mixed color portion may be formed by another configuration. Further, in the present embodiment, the case where the two-color mixed portion is provided has been described, but the three-color mixed portion may be provided. In this embodiment, the case where three color mixture portions are formed on one page has been described. However, it may be divided into a plurality of pages.
[0015]
【The invention's effect】
As described above, according to the image forming apparatus of the present invention, a slight density change is replaced with a color change by printing on a standard density original document in a state where a color mixture portion is formed by two or more developing devices. Thus, it is possible to provide a standard density original printing method for a color image forming apparatus capable of improving the accuracy of recognizing the gradation when compared with a regular color density sample.
[Brief description of the drawings]
FIG. 1 is a configuration diagram illustrating an image forming unit of a color image forming apparatus of the present invention.
FIG. 2 is a diagram showing a color image forming apparatus of the present invention.
FIG. 3 is a diagram illustrating a printing state of a standard density original according to the present invention.
[Explanation of symbols]
1, 1a to 1d: photosensitive drum 2: charging means 3: exposure means 4: developing means 4a to 4d: developing roller 5: primary transfer means 6: cleaning blade 7: neutralizing means 10: intermediate transfer belt 11: driving roller 12 : Tension roller 13: backup roller 14: secondary transfer roller 15: elastic blade 16: fixing device 21: standard density original 22: standard density original title 23: cyan density gradation concentric circle part 24: magenta density gradation concentric circle part 25 : Yellow density gradation concentric part 26: Black density gradation part 27: Cyan / magenta mixed color part 28: Cyan / yellow mixed color part 29: Magenta / yellow mixed color part

Claims (1)

In a standard density original printing method of a color image forming apparatus having a plurality of developing means and capable of printing a standard density original for comparison with a color density sample, a color mixture portion by two or more developing devices is formed on the standard density original. Print in the state,
The color mixture portion is formed by overlapping a plurality of different density portions of concentric circles of each color,
2. A standard density original printing method for a color image forming apparatus, wherein the concentric circles of the respective colors are configured to represent a darker color as they transition from the outer periphery to the inner periphery or from the inner periphery to the outer periphery.

Images