Chart manufacturing apparatus, chart manufacturing method, program, and image forming system

Abstract

Provided are a chart manufacturing device, a chart manufacturing method, a program, and an image forming system that do not require switching of a background at the time of measuring a chart with two types of backgrounds different in color from each other. This chart manufacturing device forms a chart (102) measured by application of a first background color and a second background color on a transparent base material. A first measurement background image (130) is formed on a transparent base material (100) using a coloring material corresponding to the first background color. A first patch group (122) including one or more first patches (126) is formed using a coloring material of a first color at a position corresponding to the first measurement background image. A second patch group (120) including one or more second patches (124) is formed at a position at which the first measurement background image is not formed.

Description

[Technical Field]

[0001] The present invention relates to a chart manufacturing apparatus, a chart manufacturing method, a program, and an image forming system. [Background technology]

[0002] Inkjet printing devices are known that apply white ink to form the base or other surface of printed materials using transparent substrates. For example, a color image is printed, and then a full-surface image of white ink is printed over the color image. When the printed material is viewed from the side of the substrate opposite to the printed surface, the color image is visible on a white background.

[0003] The density of white ink can be controlled using the opacity as an indicator. The opacity represents the degree to which the white ink applied to the substrate hides the underlying color of the substrate. When deriving the opacity, the white ink is measured using both a white background and a black background.

[0004] Patent Document 1 describes a printing apparatus that acquires errors in the amount of ink deposited on a transparent substrate and corrects the amount of ink deposited based on the errors. In the apparatus described in the document, white patches and process color patches such as cyan are printed on a transparent substrate, the patches are color-measured in lab space, and color correction is performed based on the color measurement data.

[0005] Figure 17 in the same document illustrates colorimetric measurements using a black and white background, with cyan, magenta, yellow, and black applied to a white background, and white applied to a black background.

[0006] Patent Document 2 describes a printing apparatus equipped with a switching mechanism that switches between a white background and a black background, where the black background is used for reading white ink and the white background is used for reading black ink, etc., and which accurately detects defective nozzles for various inks.

[0007] Patent Document 3 describes an image forming apparatus equipped with an image reading unit for reading an image formed on a transparent support. The apparatus described in the document determines whether the background color when reading the image should be black or white, and sets the background color based on the determination result. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2011-73306 [Patent Document 2] Japanese Patent Publication No. 2012-232499 [Patent Document 3] Japanese Patent Publication No. 2019-220782 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] However, the devices described in each of the three patent documents (1 to 3) each include components for switching between a white background and a black background, and the background color is switched. In other words, none of the three patent documents (1, 2, and 3) describe any ingenuity regarding charts for having only one background color. To put it another way, none of the inventions described in the three patent documents (1, 2, and 3) address the problem of devising a way to form a chart that does not require switching background colors.

[0010] This invention has been made in view of these circumstances, and aims to provide a chart manufacturing apparatus, chart manufacturing method, program, and image forming system that eliminate the need to switch backgrounds when measuring a chart using two backgrounds of different colors. [Means for solving the problem]

[0011] The chart manufacturing apparatus according to the present disclosure includes an image forming apparatus that forms a chart measured by applying a first background color and a second background color different from each other on a transparent substrate, a processor, and a storage device that stores a program executed using the processor. The processor executes the instructions of the program to form a first measurement background image on the transparent substrate using a coloring material corresponding to the first background color, and forms a first patch group including one or more first patches at a position corresponding to the first measurement background image on the transparent substrate using a coloring material of the first color, and forms a second patch group including one or more second patches at a position where the first measurement background image is not formed on the transparent substrate.

[0012] According to the chart manufacturing apparatus according to the present disclosure, when the transparent substrate is supported by applying a background using the second background color and the first patch group and the second patch group are measured, the first patch group is measured with the first measurement background image to which the coloring material corresponding to the first background color is applied as the background, and the second patch group is measured by applying the background using the second background color. Thereby, when measuring the first patch group and the second patch group, it is not necessary to switch between the different first background color and the second background color.

[0013] The patch may apply a small piece image representing the density for each color. The shape of the patch may be a rectangle.

[0014] The transparent substrate may apply a substrate having a visible light transmittance of less than 100%.

[0015] Examples of the coloring material include ink and toner.

[0016] In the chart manufacturing apparatus according to another aspect, the processor forms a first measurement background image on one surface of the transparent substrate and forms the first patch group by overlapping it on the first measurement background image.

[0017] According to such an aspect, a chart can be formed by overlapping the first patch group on the first measurement background image.

[0018] In another embodiment, the chart manufacturing apparatus includes a processor that forms a transparent image to which a transparent coloring material is applied over a first measurement background image, and forms a first patch group over the transparent image.

[0019] According to this embodiment, mixing of the coloring agent applied to the first measurement background image and the coloring agent applied to the first patch group can be suppressed.

[0020] In another embodiment, the chart manufacturing apparatus includes a processor that forms a first patch group on one side of a transparent substrate and forms a first measurement background image on the other side of the transparent substrate at positions corresponding to the positions of the first patch group.

[0021] According to this embodiment, mixing of the coloring agent applied to the first measurement background image and the coloring agent applied to the first patch group can be suppressed.

[0022] This embodiment is suitable for a double-sided machine capable of forming images on both sides of a transparent substrate.

[0023] In another embodiment of the chart manufacturing apparatus, the processor forms a first patch group on one side of a transparent substrate and forms a first measurement background image at a position that overlaps with the first patch group when the transparent substrate is folded along a fold line.

[0024] According to this embodiment, it is possible to fold the transparent substrate along the fold line and superimpose the first patch group onto the first measurement background image.

[0025] In another embodiment of the chart manufacturing apparatus, the processor forms a second patch using a first-color coloring agent.

[0026] According to this embodiment, the first patch and the second patch, formed using the first coloring agent, can be measured using different background colors.

[0027] In another embodiment, the chart manufacturing apparatus has a processor that forms first and second patches using a white coloring agent as the first coloring agent, and forms a first measurement background image using a black coloring agent as the coloring agent corresponding to the first background color.

[0028] According to this embodiment, measurements of white patches can be performed using a white background and a black background.

[0029] In another embodiment, the chart manufacturing apparatus has a processor that forms a second patch using a second coloring agent different from the first coloring agent.

[0030] According to this embodiment, a chart can be formed that includes multiple colored patch groups.

[0031] In another embodiment, the chart manufacturing apparatus includes a processor that forms a first patch using a white coloring agent as the first coloring agent, forms a second patch using at least one process coloring agent as the second color, and forms a first measurement background image using a black coloring agent as the coloring agent corresponding to the first background color.

[0032] According to this embodiment, a white patch can be measured with a black background applied, and a process color patch can be measured with a white background applied.

[0033] In another embodiment, the chart manufacturing apparatus includes a processor that forms a second measurement background image at positions corresponding to the positions of the second patch group using a coloring agent corresponding to the second background color.

[0034] According to this embodiment, measurements can be performed using the first measurement background image and the second measurement background image regardless of the color of the surface on which the transparent substrate is supported.

[0035] In another embodiment of the chart manufacturing apparatus, the processor forms a second measurement background image using a white coloring agent as a coloring agent corresponding to the second background color.

[0036] According to this embodiment, a second patch can be measured by applying a white second measurement background image.

[0037] In another embodiment, the chart manufacturing apparatus includes a processor that forms a second measurement background image having a coverage of 85 percent or more.

[0038] According to this embodiment, transparency of the second measurement background image is suppressed.

[0039] In another embodiment, the chart manufacturing apparatus has a processor that forms a first patch using a white coloring agent as the first coloring agent, and forms a first measurement background image using a black coloring agent as the coloring agent corresponding to the first background color.

[0040] According to this embodiment, a first white patch can be measured by applying a first black measurement background image.

[0041] A chart manufacturing apparatus according to another embodiment forms a first measurement background image having a coverage rate of 85 percent or more.

[0042] According to this embodiment, transparency of the first measurement background image is suppressed.

[0043] In another embodiment of the chart manufacturing apparatus, the processor forms a second patch to which the same grayscale value as the first patch is applied.

[0044] According to this embodiment, the management of the colors applied to the first patch and the colors applied to the second patch can be standardized.

[0045] In another embodiment, the chart manufacturing apparatus includes a processor that forms a first patch group in which multiple first patches with different grayscale values ​​are arranged along the transport direction of the transparent substrate, and a second patch group in which multiple second patches of the same color with different grayscale values ​​are arranged along the transport direction of the transparent substrate.

[0046] According to this embodiment, when formed using a line head, the occurrence of in-plane unevenness in each patch is suppressed.

[0047] The chart manufacturing method according to this disclosure is a chart manufacturing method for forming a chart on a transparent substrate that is measured by applying a first background color and a second background color that are different in color from each other, wherein a computer forms a first measurement background image on the transparent substrate using a coloring agent corresponding to the first background color, forms a first patch group containing one or more first patches using a coloring agent of the first color at a position on the transparent substrate corresponding to the first measurement background image, and forms a second patch group containing one or more second patches at a position on the transparent substrate where the first measurement background image is not formed.

[0048] The chart manufacturing method described herein makes it possible to obtain the same effects and advantages as the chart manufacturing apparatus described herein. The constituent elements of the chart manufacturing apparatus in other embodiments may be applied to the constituent elements of the chart manufacturing method in other embodiments.

[0049] The program relating to this disclosure is a program for manufacturing a chart that is measured by applying a first background color and a second background color that are different in color from each other, and is a program that enables a computer to perform the following functions: forming a first measurement background image on a transparent substrate using a coloring agent corresponding to the first background color; forming a first patch group containing one or more first patches using a coloring agent of the first color at positions on the transparent substrate corresponding to the first measurement background image; and forming a second patch group containing one or more second patches at positions on the transparent substrate where the first measurement background image is not formed.

[0050] The program relating to this disclosure makes it possible to obtain the same effects and advantages as the chart manufacturing apparatus relating to this disclosure. The constituent elements of the chart manufacturing apparatus relating to other embodiments may be applied to the constituent elements of the program relating to other embodiments.

[0051] The image forming system according to this disclosure comprises an image forming apparatus for forming a chart on a transparent substrate that is measured by applying a first background color and a second background color of different colors, a processor, and a storage device that stores a program executed using the processor, wherein the processor executes instructions from the program to form a first measurement background image on the transparent substrate using a coloring agent corresponding to the first background color, a first patch group containing one or more first patches using a coloring agent of the first color at a position on the transparent substrate corresponding to the first measurement background image, and a second patch group containing one or more second patches at a position on the transparent substrate where the first measurement background image is not formed.

[0052] The image forming system according to this disclosure makes it possible to obtain the same effects and advantages as the chart manufacturing apparatus according to this disclosure. The constituent elements of the chart manufacturing apparatus according to other embodiments can be applied to the constituent elements of the image forming system according to other embodiments.

[0053] An example of an image forming system is an inkjet printing system equipped with an inkjet printing device. [Effects of the Invention]

[0054] According to the present invention, when a transparent substrate is supported with a background using a second background color, and measurements are performed on the first and second patch groups, the first patch group is measured with a first measurement background image using a coloring material corresponding to the first background color as the background, and the second patch group is measured with a background using a second background color. As a result, there is no need to switch between the first and second background colors, which are different from each other, when performing measurements on the first and second patch groups. [Brief explanation of the drawing]

[0055] [Figure 1] Figure 1 is a functional block diagram of the grayscale correction data generation device. [Figure 2] Figure 2 is a functional block diagram of the correction processing unit shown in Figure 1. [Figure 3]Figure 3 is a flowchart showing the procedure for generating a tone correction LUT. [Figure 4] Figure 4 is a schematic diagram of the tone correction LUT generation process. [Figure 5] Figure 5 is an explanatory diagram of the gradation correction chart. [Figure 6] Figure 6 is a plan view of a background, showing an example of its composition. [Figure 7] Figure 7 is a schematic diagram of the grayscale correction chart for the measurement state. [Figure 8] Figure 8 is an explanatory diagram of the drive voltage applied to printing the grayscale correction chart. [Figure 9] Figure 9 is an overall diagram of the inkjet printing system according to this embodiment. [Figure 10] Figure 10 is a functional block diagram showing the electrical configuration of the inkjet printing system shown in Figure 9. [Figure 11] Figure 11 is a block diagram showing the hardware configuration of a control device applied to the inkjet printing system shown in Figure 9. [Figure 12] Figure 12 is a flowchart showing the procedure for the chart manufacturing method according to the first embodiment. [Figure 13] Figure 13 is a schematic cross-sectional view showing a tone correction chart manufactured by applying the tone correction chart manufacturing method according to the first embodiment. [Figure 14] Figure 14 is a configuration diagram showing an example of the configuration of a printing apparatus applied to a chart manufacturing apparatus according to the second embodiment. [Figure 15] Figure 15 is a schematic cross-sectional view showing a chart manufactured using the chart manufacturing apparatus according to the second embodiment. [Figure 16] Figure 16 is a schematic cross-sectional view showing a chart manufactured using the chart manufacturing apparatus and chart manufacturing method according to the third embodiment. [Figure 17] Figure 17 is a schematic cross-sectional view showing a chart manufactured using the chart manufacturing apparatus according to the fourth embodiment. [Figure 18] Figure 18 is a schematic diagram showing the measurement status of the chart shown in Figure 17. [Modes for carrying out the invention]

[0056] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In this specification, identical components are denoted by the same reference numerals, and redundant descriptions are omitted where appropriate.

[0057] [Example of a configuration for a tone correction data generation device] Figure 1 is a functional block diagram of the grayscale correction data generation device. The grayscale correction data generation device 10 shown in the figure is connected to a measuring instrument 12, a printer 14, and a display device 16.

[0058] The gradation correction data generation device 10 generates gradation correction data that is applied to correct the nonlinearity between gradation values ​​and density values ​​in image data to be printed using the printer 14. The printer 14 performs printing based on the image data to which the gradation values ​​corrected by the gradation correction data are applied. Hereinafter, the printer 14 will be described as an inkjet printing device equipped with an inkjet head.

[0059] The gradation correction data generation device 10 includes an image data storage unit 20. The image data storage unit 20 stores gradation correction chart data that represents a gradation correction chart to be printed on a substrate. The image data storage unit 20 may also store data representing the target density values ​​for each gradation value that will be reproduced when the gradation correction chart is printed. Note that storage refers to saving data to memory and is synonymous with memory, recording, and retention.

[0060] The gradation correction data generation device 10 includes a printer control unit 22. The printer control unit 22 reads gradation correction chart data from the image data storage unit 20 and generates an ejection control signal based on the gradation correction chart data. The printer 14 prints the gradation correction chart based on the ejection control signal.

[0061] The printer control unit 22 displays various information about the printer 14 on the display device 16. The display device 16 uses a touch panel system and displays the printer operation screen 16A. The user can operate the printer operation screen 16A to send various information to the printer 14.

[0062] The measuring instrument 12 measures the density values ​​of patches that make up the gradation correction chart printed on the substrate. A spectrophotometer may be used for the measuring instrument 12. The measuring instrument 12 transmits the measurement results to the gradation correction LUT generation unit 26.

[0063] The grayscale correction data generation device 10 includes a measuring instrument control unit 24. The measuring instrument control unit 24 sets measurement conditions for the measuring instrument 12 and controls the measurement of the grayscale correction chart using the measuring instrument 12.

[0064] The gradation correction data generation device 10 includes a gradation correction LUT generation unit 26 and a LUT storage unit 28. The gradation correction LUT generation unit 26 generates a gradation correction LUT that defines the conversion relationship between gradation values ​​and density values. LUT is an abbreviation for lookup table.

[0065] Specifically, the measurement data for each tone value patch in the tone correction chart is compared with the target density value for each tone value, the tone value that achieves the target density value is derived, and a tone correction LUT representing the conversion relationship between tone values ​​and density values ​​is generated.

[0066] The gradation correction LUT generation unit 26 generates a gradation correction LUT for each color. The gradation correction LUT generation unit 26 generates a gradation correction LUT for various conditions such as the type of ink, the type of substrate, and the printer settings. The generation of a gradation correction LUT as referred to here may include updating an existing gradation correction LUT.

[0067] The LUT storage unit 28 stores the tone correction LUTs generated using the tone correction LUT generation unit 26. The LUT storage unit 28 stores tone correction LUTs for each color and for various conditions.

[0068] The grayscale correction data generation device 10 includes a correction processing unit 30. The correction processing unit 30 includes a grayscale correction processing unit 31. The correction processing unit 30 may also include various correction processing units applied to the grayscale correction chart data, such as an in-plane unevenness correction processing unit and a non-emission nozzle correction processing unit. Note that the various correction processing units, such as the in-plane unevenness correction processing unit, are not shown in Figure 1.

[0069] The gradation correction processing unit 31 corrects the gradation values ​​for each color by referring to the gradation correction LUT. The printer control unit 22 generates an ejection control signal based on the gradation correction chart data with corrected gradation values ​​and sends the ejection control signal to the printer 14. The printer 14 prints the gradation correction chart based on the ejection control signal.

[0070] The image data storage unit 20, correction processing unit 30, printer control unit, and printer 14 in the grayscale correction data generation device 10 shown in Figure 1 constitute a chart manufacturing apparatus according to this embodiment. Details of the chart manufacturing apparatus will be described later.

[0071] [Example of correction processing unit configuration] Figure 2 is a functional block diagram of the correction processing unit shown in Figure 1. The correction processing unit 30 shown in the figure can be a computer equipped with one or more processors and one or more memories. The processor executes a program stored in memory to realize the various functions of the correction processing unit 30. .Ko As an example of a computer, a personal computer Examples include .

[0072] The correction processing unit 30 includes a gradation correction processing unit 31, an in-plane uniformity correction processing unit 52, and a non-discharge correction processing unit 54. The gradation correction processing unit 31 image The chart data for tone correction is read from the data storage unit 20.

[0073] The gradation correction processing unit 31 processes the gradation correction chart data in cyan, magenta, and yellow 、The data is broken down into color-specific gradation correction chart data for black and white. The gradation correction processing unit 31 corrects the gradation values ​​for each color by referring to the color-specific gradation correction LUTs stored in the LUT storage unit 28 for each color-specific gradation correction chart data. Figure 2 shows an example of a gradation correction LUT corresponding to a tone curve that represents the relationship between gradation values ​​and density values.

[0074] The in-plane unevenness correction processing unit 52 corrects in-plane unevenness in the patches that make up the gradation correction chart. Specifically, the in-plane unevenness correction processing unit 52 corrects the ejection amount for each nozzle according to the ejection characteristics of each nozzle of the inkjet head provided in the printer 14 shown in Figure 1.

[0075] The non-discharge correction processing unit 54 performs correction of the non-discharge nozzle. Specifically, the non-discharge correction processing unit 54 masks the non-discharge nozzle and performs alternative discharge using a nozzle in the vicinity of the non-discharge nozzle.

[0076] As a result of performing in-plane unevenness correction and non-ejecting nozzle correction, the printer 14 can print a gradation correction chart that includes patches in which in-plane unevenness is suppressed and streaks caused by non-ejecting nozzles are suppressed.

[0077] The gradation correction chart data corrected using the correction processing unit 30 is sent to the printer control unit 22. The printer control unit 22 generates an ejection control signal based on the received gradation correction chart data and sends the ejection control signal to the printer 14. The printer 14 prints the gradation correction chart based on the ejection control signal.

[0078] [Procedure for generating a tone correction LUT] Figure 3 is a flowchart showing the procedure for generating a tone correction LUT. In the print condition setting step S10, the printer control unit 22 shown in Figure 1 sets the print conditions for the tone correction chart for the printer 14. Examples of print conditions include the type of ink and the type of substrate.

[0079] In the gradation correction chart printing process S12, the printer control unit 22 prints a gradation correction chart based on the gradation correction chart data that has undergone various correction processes, such as gradation correction processing.

[0080] The gradation correction chart printing process S12 includes several steps, which will be described later. Each step constituting the gradation correction chart printing process S12 constitutes a chart method applied to the chart manufacturing apparatus. Details of the gradation correction chart printing process S12 will be described later.

[0081] In the grayscale correction chart measurement step S14, the grayscale correction chart to be printed in the grayscale correction chart printing step S12 is measured using the measuring instrument 12 shown in Figure 1. The grayscale correction chart may be measured using either automatic or manual measurement.

[0082] In automated measurement, a substrate printed with a grayscale correction chart output from the printer 14 is transported to the measuring instrument 12, the substrate is set in the measuring instrument 12, and the grayscale correction chart is measured.

[0083] In manual measurement, the substrate on which the grayscale correction chart printed from the printer 14 is printed is manually placed into the measuring instrument 12, and the grayscale correction chart is measured.

[0084] In the gradation correction LUT generation process S16, the gradation correction LUT generation unit 26 acquires measurement data for the gradation correction chart from the measuring instrument 12 and generates a gradation correction LUT based on the acquired measurement data for the gradation correction chart.

[0085] Specifically, in the tone correction LUT generation process S16, the tone correction LUT generation unit 26 generates a tone correction LUT that corrects the correspondence between tone values ​​and density values. An example of a tone curve in which the relationship between tone values ​​and density values ​​for each color has been corrected is shown in Figure 2.

[0086] Figure 4 is a schematic diagram of the tone correction LUT generation process. Figure 4 uses four types of schematic graphs to illustrate the processing of each step in the tone correction LUT generation process S16. Here, we will explain the method of correcting an existing tone correction LUT.

[0087] Line 60 shows the relationship between the input signal value and the output signal value of an existing tone correction LUT. In an existing tone correction LUT, the input signal value and the output signal value are the same. If the input signal value is X and the output signal value is Y, the output signal value Y is expressed as Y=X. The existing tone correction LUT referred to here is the tone correction LUT applied to the printing of the tone correction chart.

[0088] Curve 62 schematically represents the relationship between the signal value applied to printing each patch of the gradation correction chart and the target density value. The target density value corresponds to the density value in curve 62. A table showing the relationship between the signal value applied to printing each patch of the gradation correction chart and the target density value is stored in the image data storage unit 20 shown in Figure 1.

[0089] Curve 64 schematically shows the relationship between the signal values ​​applied to the printing of each patch of the gradation correction chart and the measurement data of each patch acquired in the gradation correction chart measurement process S14. The measurement data of each patch corresponds to the density values ​​of curve 64.

[0090] Ideally, the measurement data for each patch in the gradation correction chart should match the target density value. However, due to variations in the ejection characteristics of the inkjet head, the measurement data for each patch will differ from the target density value.

[0091] Curve 66 schematically shows a tone correction LUT where the signal value that reproduces the target density value is used as the output signal value, and the tone value derived based on the image data is used as the input signal value.

[0092] The tone correction LUT is generated by applying the following steps. First, the signal value corresponding to the target density value is derived from a table representing the relationship between the signal value applied to printing each patch of the tone correction chart, represented as curve 62, and the target density value.

[0093] Next, using the relationship between the signal values ​​applied to the printing of each patch of the gradation correction chart, represented as curve 64, and the measurement data for each patch, a signal value that reproduces the target density value is derived. The signal value that reproduces the target density value derived from curve 64 is assigned to the input signal value applied to the target density value.

[0094] This derives the relationship between the uncorrected signal value already assigned to each patch and the corrected signal value that reproduces the target density value, and generates a tone correction LUT that takes the uncorrected signal value as input and the corrected signal value as output.

[0095] In the tone correction LUT storage process S18, the tone correction LUT generation unit 26 stores the tone correction LUT in the LUT storage unit 28. The printer 14 reads the tone correction LUT stored in the LUT storage unit 28 and applies the tone correction LUT to the image data processing.

[0096] [Density control of white images] An example of a white image printed using white ink is a white background for a color image printed on a transparent substrate. It is important that the white image applied as a background for a color image is opaque. Generally, the degree of transparency of a white image can be evaluated using the opacity rate as an evaluation index. The opacity rate is calculated by applying a white background and a black background, measuring the density values ​​of multiple white patches with different signal values ​​representing gradation, and applying the calculation method specified in the standard.

[0097] For example, the opacity of a white patch can be calculated by applying Method B specified in the Japanese Industrial Standard JIS K 5600-4-1, Opacity. JIS K 5600-4-1, Opacity is a Japanese Industrial Standard created by translating ISO / FDIS 6504-3, published in 1998, without changing the technical content or the format of the standard document. JIS is an abbreviation for Japanese Industrial Standards, and ISO is an abbreviation for International Organization for Standardization.

[0098] The term "white" in "white images" and "white ink" is not limited to strictly white, which reflects 100 percent of all wavelengths of visible light, but includes white in a broad sense as generally recognized. "White ink" refers to inks sold under names such as "white ink" or "white ink, etc." An example of white ink is ink containing white pigments such as titanium dioxide particles. Note that "white" is synonymous with "white" and "white color," and these terms are interchangeable.

[0099] In this embodiment, a white patch is measured using two different backgrounds, and a gradation correction LUT is created by associating the signal value applied when printing the white patch with the opacity that manages the white ink. This makes it possible to directly control the density of the white ink using the signal value applied to printing.

[0100] [Specific examples of charts for tone correction] Figure 5 is an explanatory diagram of the gradation correction chart. Figure 5 shows the gradation correction chart 102 printed on the substrate 100. The substrate 100 is a transparent sheet-like medium, and an impermeable medium is applied. Examples of materials for the substrate 100 include ONY (Oriented Nylon), OPP (Oriented PolyPropylene), and PET (PolyEthylene Terephthalate).

[0101] Non-permeable means that it is non-permeable to water-based inks, as described later. Transparent means that the transmittance of visible light is 30% or more and 100% or less, preferably 70% or more and 100% or less.

[0102] The gradation correction chart 102 includes a process color patch group 112, which consists of multiple patches 110 printed using process color inks. The process color patch group 112 includes a cyan patch group 112C, a magenta patch group 112M, a yellow patch group 112Y, and a black patch group 112K.

[0103] The cyan patch group 112C consists of multiple cyan patches 110C. The magenta patch group 112M consists of multiple magenta patches 110M. The yellow patch group 112Y consists of multiple yellow patches 110Y. The black patch group 112K consists of multiple black patches 110K.

[0104] The gradation correction chart 102 includes a spot color patch group 116, which consists of multiple spot color patches 114 printed using spot color inks. The spot color patch group 116 includes an orange patch group 116O, a green patch group 116G, and a violet patch group 116V.

[0105] The orange patch group 116O consists of multiple orange patches 114O. The green patch group 116G consists of multiple green patches 114G. The violet patch group 116V consists of multiple violet patches 114V.

[0106] The gradation correction chart 102 includes a first white patch group 120 and a second white patch group 122. The first white patch group 120 includes multiple first white patches 124. The second white patch group 122 includes multiple second white patches 126.

[0107] The multiple first white patches 124 constituting the first white patch group 120 have increasing grayscale values ​​from the downstream side to the upstream side in the substrate transport direction. The first white patch 124 at the downstream end in the substrate transport direction is applied to the minimum grayscale value. The first white patch 124 at the upstream end in the substrate transport direction is applied to the maximum grayscale value.

[0108] The first white patch group 120 shown in Figure 5 consists of 16 first white patches 124. For example, if the grayscale value is represented by a number from 0 to 255, the grayscale values ​​of the 16 first white patches 124 are set with a minimum value of 0 and a maximum value of 255, increasing by 17 each time.

[0109] Multiple first white patches 124 constituting the second white patch group 122 are to which the same gradation value as the second white patch 126 is applied. That is, the first white patches 124 and the second white patch 126 that are in the same position in the substrate transport direction are to which the same gradation value is applied.

[0110] The first white patch group 120 and the second white patch group 122 are positioned at different locations in the substrate width direction, which is perpendicular to the substrate transport direction. Note that "perpendicular" here may include situations where the angle between the two directions is less than 90 degrees or greater than 90 degrees, but where the same effects and advantages as a 90-degree angle are obtained.

[0111] The process color patch group 112 and the spot color patch group 116 are applied to the same gradation values ​​as the first white patch group 120. The process color patch group 112 and the spot color patch group 116 are positioned at different locations in the substrate width direction.

[0112] Each of the patch groups of each color constituting the process color patch group 112 is positioned at a different location in the substrate width direction. Similarly, each of the patch groups of each color constituting the spot color patch group 116 is positioned at a different location in the substrate width direction.

[0113] The gradation correction chart 102 has patches of each color arranged in order of gradation values ​​along the substrate transport direction, and patches of different colors arranged along the substrate width direction have the same gradation value. Here, "identical" is not limited to strict identicalness, but may include substantially identical values.

[0114] The gradation correction chart 102 has a first measurement start position mark 106 and a second measurement start position mark 108 printed on it. The first measurement start position mark 106 is printed using black ink. The second measurement start position mark 108 is printed using white ink.

[0115] The first measurement start position mark 106 represents the measurement start position for the process color patch group 112, the spot color patch 114, and the first white patch group 120 in the gradation correction chart 102. The second measurement start position mark 108 represents the measurement start position for the second white patch group 122.

[0116] The gradation correction chart 102 has a black measurement background image 130 printed on it using black ink. The black measurement background image 130 is the area where the second white patch group 122 is printed, and the process color patch group 112 and the spot color patch group 116 are placed in areas that are not printed. An example of black ink is ink containing carbon black particles. Further details of the black measurement background image 130 will be described later.

[0117] The black measurement background image 130 described in the embodiment is an example of a first measurement background image. The second white patch 126 described in the embodiment is an example of a first patch. The second white patch group 122 described in the embodiment is an example of a first patch group containing one or more first patches. The first white patch 124 described in the embodiment is an example of a second patch. The first white patch group 120 described in the embodiment is an example of a second patch group containing one or more second patches.

[0118] Furthermore, the patch 110 constituting the process color patch group 112 and the patch 110 constituting the spot color patch group 116 described in the embodiment are other examples of the second patch. The process color patch group 112 and the spot color patch group 116 described in the embodiment are other examples of the second patch group. The white ink constituting the second white patch 126 described in the embodiment is an example of the coloring material for the first color.

[0119] The printing of the first white patch 124 described in the embodiment is an example of forming one or more second patches. The printing of the patch 110 constituting the process color patch group 112 and the patch 110 constituting the spot color patch group 116 described in the embodiment is an example of forming one or more patches included in the second patch group. The process color and spot color described in the embodiment are examples of second colors.

[0120] [Example of background configuration applied to the measurement of a tone correction chart] Figure 6 is a plan view of the background, showing an example of its configuration. The white background 202 shown in this figure is applied to the measuring instrument 12 shown in Figure 1. When measuring the gradation correction chart 102 printed on the substrate 100 shown in Figure 5, the substrate 100 is supported using the stage 201.

[0121] The substrate support surface 201A that supports the substrate 100 of the stage 201 has a white background 202 formed on it. For example, the formation of the white background 202 on the substrate support surface 201A can be achieved by attaching a sheet with the white background 202 printed on it to the substrate support surface 201A. The formation of the white background 202 on the substrate support surface 201A can also be achieved by applying a surface treatment such as painting.

[0122] [Measurement of gradation correction chart and calculation of gradation correction data] Figure 7 is a schematic diagram of the gradation correction chart in the measurement state. Note that in Figure 7, some of the symbols shown in Figure 5 are omitted. The same applies to Figures 17 and 18. As shown in the figure, the gradation correction chart 102 is aligned with the white background 202, and the measurement of the gradation correction chart 102 is performed.

[0123] Specifically, for each of the plurality of first white patches 124 that constitute the first white patch group 120, the Y value in the CIEXYZ color space system is acquired. Similarly, for each of the plurality of second white patches 126 that constitute the second white patch group 122, the Y value in the CIEXYZ color space system is acquired.

[0124] The measured value of the first white patch 124 is affected by the density of the white background 202. Similarly, the measured value of the second white patch 126 is affected by the density of the black measurement background image 130. For the purpose of avoiding the influence of the white background 202 on the measured value of the first white patch 124 and the influence of the black measurement background image 130 on the second white patch 126, the measured values of the first white patch 124 and the second white patch 126 are normalized using the density value of the white background 202 and the density value of the black measurement background image 130. <000>

[0125] Let the Y value of the observation light source be Y L and the Y value of the black measurement background image 130 be Y bk When the measured value obtained with the black measurement background image 130 as the background is Y mk the normalized Y value Y nb is expressed as Y nb =(Y mk -Y bk ) / (Y L -Y bk ). In other words, the measured value Y mb which is an absolute value, is converted to the relative Y value Y nb with the black measurement background image 130 as the reference.

[0126] When using the white background 202, let the Y value of the white background 202 be Y wh and the measured value obtained with the white background 202 as the background be Y mw the normalized Y value Y nw is expressed as Y nw =(Y mw -Y wh ) / (Y L -Y wh ). The Y value Y whThe Y value obtained by measuring the non-formed area of ​​the gradation correction chart 102 on the substrate 100 can be applied. Y value of black measurement background image 130 bk The same applies to this matter.

[0127] Y value based on measurement data from the first white patch 124 nw And the Y value based on measurement data from the second white patch 126. nb Using this, the opacity Y for each grayscale value in white ink nb / Y nw This is calculated.

[0128] The target opacity for each grayscale value in the white ink is obtained, and the target opacity representing the density of the target white ink is compared with the opacity calculated from the measurement data of each patch. The difference between the calculated opacity and the target opacity is then calculated. Based on the calculated difference in opacity, a grayscale correction LUT is generated to be applied to the white ink.

[0129] Specifically, following the procedure of the tone correction LUT generation process S16 in Figure 3, which will be explained using Figure 4, the density value is replaced with the opacity, and a tone correction LUT applied to the white ink is generated. The tone correction LUT is stored in the LUT storage unit 28 shown in Figure 1.

[0130] The LUT applied to the white ink represents the relationship between the signal value representing the gradation value and the opacity rate, which is an evaluation index value for the white patch. For the white ink, the signal value that achieves the target opacity rate is derived, enabling printing that reproduces the target density value. It also allows for adjustment of the white ink density value to correspond to the target opacity rate when the density value is changed.

[0131] For example, in printing a white image where the opacity of the white ink is set to 53 percent, if the opacity of the white is changed to 51 percent for the purpose of reducing the cost of the white ink, the signal value representing the gradation value for which the opacity is 51 percent can be obtained by referring to the white gradation correction LUT.

[0132] In this way, when the opacity of the white ink is changed, it is not necessary to derive a signal value representing the gradation value corresponding to the changed opacity of the white ink based on the printing and measurement of the gradation correction chart 102.

[0133] For process color inks such as cyan and spot color inks such as orange, the LUTs for each color stored in the LUT storage unit 28 shown in Figure 1 are corrected based on the Y values ​​of the CIEXYZ color system for each patch 110 for each color obtained in the measurement of the gradation correction chart 102.

[0134] For process inks other than white, such as cyan, the Y value of the observation light source is also used in LUT correction. L and Y on a white background 202 Value Y wh Y value normalized using n The above applies. Note that the normalization of measured values ​​using the density of a white background (202) is not limited to the above example. Other methods may be applied if it is possible to convert absolute measured values ​​to relative values ​​based on the background color.

[0135] When converting absolute values ​​to relative values, the higher the relative density contrast between patch 110 and the white background 202, the more likely the correction accuracy of the LUT can be improved. Therefore, it is preferable to have a configuration in which the density of the white background 202 is measured, and a warning is issued when the measured density value is below a specified threshold.

[0136] An example of a warning is to display text information representing the content of the warning on the display device 16 shown in Figure 1, prompting the user to replace the white background 202, etc. The Y value of the white background 202 can be obtained by measuring the non-formed area of ​​the gradation correction chart 102 on the substrate 100.

[0137] When single-pass printing is applied to the printer 14, the arrangement direction of multiple patches 110 of the same color is preferably parallel to the substrate transport direction. When multiple patches 110 of the same color are arranged parallel to the substrate transport direction, the uniformity of density within the plane of each patch 110 is relatively improved, and the correction accuracy of the LUT may be relatively improved. Note that the term "parallel" here may include substantially parallel lines that intersect but produce the same effect as parallel lines.

[0138] When the grayscale correction chart 102 is measured, if the density uniformity within the white background 202 is relatively high, the correction accuracy of the LUT may be relatively improved. Therefore, it is preferable to measure the density unevenness within the white background 202 and issue a warning if the measured density unevenness exceeds a specified threshold. The warning may be implemented in the manner exemplified above. Upon seeing the warning, the user can replace and clean the white background 202 to suppress the density unevenness within the white background 202.

[0139] [Drive voltage applied to printing the grayscale correction chart] Figure 8 is an explanatory diagram of the drive voltage applied to printing the grayscale correction chart. Figure 8 uses a graph format to illustrate the drive voltage supplied to the piezoelectric inkjet head equipped in the printer 14 shown in Figure 1 for one ejection cycle.

[0140] In the graph shown in Figure 8, the horizontal axis represents time, and the unit of the horizontal axis is microseconds. The vertical axis of the graph shown in the same figure represents voltage, and the unit of the vertical axis is volts. Note that the values ​​shown in Figure 8 are examples and can be appropriately specified according to the printing conditions and the specifications of the piezoelectric element equipped in the inkjet head.

[0141] The inkjet head employs a continuous firing drive system, and one or more ejection drive pulses corresponding to the ejection volume are supplied from among the multiple ejection drive pulses that make up the drive waveform 300 shown in Figure 8. This allows the inkjet head to eject large, medium, and small droplets, each with a different volume.

[0142] For example, when dispensing a small droplet, the dispensing drive pulse 312 is applied. When dispensing a medium-sized droplet, the dispensing drive pulses 306, 308, 310, and 312 are applied.

[0143] When dispensing large droplets, the dispensing drive pulses 302, 304, 306, 308, 310, and 312 are applied.

[0144] The drive waveform element following the ejection drive pulse 312 is the reverberation suppression waveform element 314. The reverberation suppression waveform element 314 can be added in all cases, including large, medium, and small ink droplets, for the purpose of suppressing the vibration of the ink immediately after the ink droplet is ejected.

[0145] The same printing conditions as for normal printing are applied to the printing of the tone correction chart 102 shown in Figure 5. That is, for each color, at least one of the patches that make up the patch group that constitutes the tone correction chart 102 is printed by combining multiple sizes of dots.

[0146] For example, patch 110, which has a relatively small gradation value, will only have small dots corresponding to small droplets applied, while patch 110, which has a relatively small gradation value, will have both small dots and medium dots corresponding to medium droplets applied.

[0147] [Example configuration of an inkjet printing system according to an embodiment] Figure 9 is an overall configuration diagram of an inkjet printing system according to an embodiment. The inkjet printing system 400 includes a digital printing device 406 that applies a single-pass printing method to print a color image onto a transparent substrate 401.

[0148] In this embodiment, flexible packaging such as plastic film is exemplified as the base material 401. The base material 401 may be a single layer or multiple layers stacked together. The base material 401 may be in a roll-to-roll continuous form or in the form of a sheet cut to a specified length. The base material 401 may also be called a medium, media, sheet, film, or substrate. The base material 401 shown in Figure 9 corresponds to the base material 100 shown in Figure 5.

[0149] The inkjet printing system 400 includes a substrate supply device 402, a first intermediate transport device 404, a printing device 406, a second intermediate transport device 408, a measuring device 410, a drying device 412, and an accumulation device 414. Each part will be described in detail below.

[0150] [Base material supply device] When the substrate 401 is in a continuous form, the substrate supply device 402 includes a roll storage section for accommodating the roll on which the substrate 401 is wound. When the substrate 401 is in a single-sheet form, the substrate supply device 402 includes a tray for accommodating the substrate 401. The substrate supply device 402 supplies the substrate 401 to the first intermediate transport device 404 in accordance with the printing control of the printing device 406. The substrate supply device 402 may include a correction mechanism for correcting the orientation of the substrate 401.

[0151] [First Intermediate Conveying Device] The first intermediate transport device 404 transfers the substrate 401 supplied from the substrate supply device 402 to the printing device 406. The first intermediate transport device 404 can be configured with known configurations depending on the form of the substrate 401. The arrow line from the substrate supply device 402 to the first intermediate transport device 404 indicates the substrate transport direction.

[0152] [Printing device] The printing device 406 includes an inkjet head 420C, an inkjet head 420M, an inkjet head 420Y, an inkjet head 420K, and an inkjet head 420W.

[0153] The inkjet heads 420C, 420M, 420Y, 420K, and 420W are arranged in the order described above, from upstream to downstream, along the substrate transport direction.

[0154] Inkjet head 420C ejects cyan ink. Inkjet head 420M ejects magenta ink. Inkjet head 420Y ejects yellow ink. Inkjet head 420K ejects black ink. Inkjet head 420W ejects white ink.

[0155] The inkjet head 420C, etc., can be a line head in which multiple nozzles are arranged over a length exceeding the total length of the substrate 401 in the substrate width direction. The multiple nozzles provided in the inkjet head 420C, etc., are arranged in a two-dimensional configuration such as a matrix arrangement.

[0156] The inkjet head 420C and similar models can be fitted with a piezoelectric ejection system that includes a piezoelectric element as the ejection pressure element for generating ejection pressure. The inkjet head 420C and similar models can also be fitted with a thermal system that ejects ink by utilizing the film boiling phenomenon of the ink.

[0157] The printing apparatus 406 forms a color image on a transparent substrate 401 using color inks such as cyan ink, and then forms a white image to serve as the background image by overlaying it with white ink. The printed material produced using the substrate 401 allows the color image to be visible when the substrate 401 is viewed from a non-printed surface.

[0158] The printing apparatus 406 includes a printing drum 422. The printing drum 422 has a cylindrical shape. The printing drum 422 has a substrate support area on its circumferential surface for supporting the substrate 401. The substrate support area is not shown in the illustration.

[0159] The rotation axis of the printing drum 422 is connected to a motor (not shown) via a drive mechanism (not shown). When the motor rotates, the printing drum 422 rotates in the direction indicated by the arrow. When the printing drum 422 rotates, the substrate 401 supported on the circumferential surface of the printing drum 422 is conveyed along the direction of rotation of the printing drum 422.

[0160] The substrate support area has multiple suction holes formed therein. The multiple suction holes are arranged according to a predetermined pattern. The multiple suction holes communicate with an suction channel (not shown). The suction channel is connected to an suction pump (not shown). By operating the suction pump and generating negative pressure in the multiple suction holes, the substrate 401 is supported by suction on the circumferential surface of the printing drum 422.

[0161] The transport method for the substrate 401 in the printing apparatus 406 is not limited to a transport method using the printing drum 422. For example, a transport method using a transport belt and a transport method using multiple rollers can be applied.

[0162] [Second Intermediate Conveyor Device] The second intermediate conveying device 408 transfers the substrate 401 received from the printing drum 422 to the measuring device 410. The second intermediate conveying device 408 can be configured in the same way as the first intermediate conveying device 404. The arrow lines shown for the second intermediate conveying device 408 indicate the substrate conveying direction in the second intermediate conveying device 408.

[0163] [Measuring device] The measuring device 410 comprises a concentration meter 430, a plurality of reading and transport rollers 432, and a stage 434. The measuring device 410 is equipped with a lighting device. The illustration of the lighting device is omitted. The concentration meter 430 shown in Figure 9 corresponds to the measuring device 12 shown in Figure 1. The stage 434 shown in Figure 9 corresponds to the stage 201 provided in the measuring device 12 shown in Figure 1.

[0164] The density meter 430 shown in Figure 9 can measure the gradation correction chart printed on the substrate 401, similar to the meter 12 shown in Figure 1. The inkjet printing system 400 can generate gradation correction data for each color based on the measurement data of the gradation correction chart, and generate a gradation correction LUT for each color based on the gradation correction data for each color.

[0165] Figure 9 illustrates a roller transport method as the transport method for the substrate 401 in the measuring device 410, but other methods such as a belt transport method and a drum transport method can be applied to the transport method for the substrate 401 in the measuring device 410.

[0166] The measuring device 410 may include an imaging device that images a test pattern printed on the substrate 401. The inkjet printing system 400 can detect ejection abnormalities of the inkjet head 420C, etc., based on the imaging data of the test pattern.

[0167] [Drying equipment] The drying apparatus 412 performs a drying process on the printed substrate 401. The drying apparatus 412 may be equipped with a heater and a fan, and a configuration may be applied to blow hot air onto the printed substrate 401. The drying apparatus 412 includes a drying and conveying section for conveying the printed substrate 401. Known conveying methods such as drum conveying, belt conveying, and roller conveying may be applied as the conveying method for the printed substrate 401. The arrow lines shown in the drying apparatus 412 indicate the substrate conveying direction of the drying apparatus 412.

[0168] [Integration device] The stacking device 414 receives the substrate 401 from the drying device 412. If the substrate 401 is in a continuous form, the stacking device 414 includes a roll storage section for storing the roll on which the substrate 401 is wound. If the substrate 401 is in a single-sheet form, the stacking device 414 includes a tray for storing the substrate 401.

[0169] [Electrical configuration of an inkjet printing system] Figure 10 is a functional block diagram showing the electrical configuration of the inkjet printing system shown in Figure 9. The inkjet printing system 400 comprises a system control unit 460, a transport control unit 462, a printing control unit 466, a measurement control unit 468, a drying control unit 470, and an information acquisition unit 472.

[0170] The system control unit 460 comprehensively controls the overall operation of the inkjet printing system 400. The system control unit 460 transmits command signals to various control units. The system control unit 460 functions as a memory controller that controls the storage of data in memory 474 and the reading of data from memory 474.

[0171] The system control unit 460 acquires sensor signals transmitted from the sensor 476 and transmits command signals based on the sensor signals to various control units. The sensor 476 includes position detection sensors and temperature sensors provided in various parts of the inkjet printing system 400.

[0172] The transport control unit 462 sets transport conditions based on command signals transmitted from the system control unit 460 and controls the operation of the transport device 464 based on the set transport conditions. The transport device 464 shown in Figure 10 includes the first intermediate transport device 404, the printing drum 422, the reading transport roller 432, and the drying transport device provided in the drying device 412 shown in Figure 9. The transport device 464 may also include the substrate supply device 402 and the accumulation device 414.

[0173] The print control unit 466 sets printing conditions based on command signals transmitted from the system control unit 460 and controls the operation of the printing device 406 based on the set printing conditions. The print control unit 466 shown in Figure 10 has the functions of the printer control unit 22 shown in Figure 1.

[0174] The print control unit 466 includes an image processing unit that performs color separation processing, color conversion processing, correction processing for each process, and halftone processing on image data for printing to generate halftone data for each color.

[0175] The print control unit 466 includes a drive voltage generation unit that generates a drive voltage to be supplied to the inkjet head 420C, etc., based on halftone data for each color. The print control unit 466 also includes a drive voltage output unit that supplies a drive voltage to the inkjet head 420C.

[0176] The print control unit 466 may use the inkjet head 420C shown in Figure 9 to print a gradation correction chart that includes cyan, magenta, yellow, black, and white patch groups based on gradation correction chart data.

[0177] When the print control unit 466 generates a halftone image for the gradation correction chart, it generates a multi-level halftone image and, based on the multi-level halftone image, combines multiple types of dots of different sizes to print the gradation correction chart.

[0178] When printing a gradation correction chart, the print control unit 466 arranges multiple patches that make up each color patch group along the substrate transport direction.

[0179] The print control unit 466 may have the functions of the tone correction LUT generation unit 26 and the correction processing unit 30 shown in Figure 1. The inkjet printing system 400 shown in Figure 10 may have a tone correction data generation unit having the same functions as the tone correction data generation device 10 shown in Figure 1, separate from the print control unit 466.

[0180] Of the print control unit 466 shown in Figure 10, the processing unit corresponding to the grayscale correction data generation device 10 shown in Figure 1 acquires measurement data for the grayscale correction chart from the measurement control unit 468 and generates a grayscale correction LUT based on the measurement data for the grayscale correction chart.

[0181] The measurement control unit 468 sets measurement conditions based on command signals transmitted from the system control unit 460 and controls the operation of the measuring device 410 based on the set measurement conditions. The measurement control unit 468 shown in Figure 10 may have the functions of the measuring instrument control unit 24 shown in Figure 1.

[0182] The measurement control unit 468 may issue a warning if the density value of the background formed on the stage 434 is below a specified threshold. The measurement control unit 468 may also issue a warning if the density unevenness within the background formed on the stage 434 is above a specified threshold.

[0183] The drying control unit 470 sets the processing conditions for the main drying process based on the command signals transmitted from the system control unit 460, and controls the operation of the drying apparatus 412 based on the set processing conditions.

[0184] The information acquisition unit 472 acquires various types of information applicable to the control of the inkjet printing system 400. The system control unit 460 transmits command signals to various control units based on the various types of information acquired using the information acquisition unit 472.

[0185] Memory 474 can store various data, parameters, and programs applied to the inkjet printing system 400. Memory 474 can function as the LUT storage unit 28 shown in Figure 1.

[0186] Figure 11 is a block diagram showing the hardware configuration of a control device applied to the inkjet printing system shown in Figure 9. The control device 500 provided in the inkjet printing system 400 comprises a processor 502, a computer-readable medium 504 which is a non-temporary tangible object, a communication interface 506, and an input / output interface 508.

[0187] The control device 500 is a computer. The computer may be a server, a personal computer, a workstation, or a tablet device.

[0188] The processor 502 includes a CPU (Central Processing Unit). The processor 502 may also include a GPU (Graphics Processing Unit). The processor 502 is connected to a computer-readable medium 504, a communication interface 506, and an input / output interface 508 via a bus 510. The input device 512 and the display device 514 are connected to the bus 510 via the input / output interface 508.

[0189] The processor 502 can function as a first processor that performs processing related to the generation of gradation correction data, a second processor that performs processing related to image formation, and a third processor that performs processing related to measurement.

[0190] The computer-readable medium 504 includes memory, which is the main memory, and storage, which is the auxiliary memory. The computer-readable medium 504 may include semiconductor memory, hard disk drives, and solid-state drives, etc. The computer-readable medium 504 may include any combination of multiple devices.

[0191] Furthermore, hard disk drives can be referred to as HDDs, which are abbreviations for Hard Disk Drives. Solid state drives can be referred to as SSDs, which are abbreviations for Solid State Drives.

[0192] The control device 500 is connected to a network via a communication interface 506 and is capable of communicating with external devices. The network may be a LAN (Local Area Network), etc. Note that the network diagram is omitted.

[0193] The computer-readable medium 504 stores a transport control program 520, a print control program 522, a measurement control program 524, a drying control program 526, and a gradation correction data generation program 528.

[0194] The transport control program 520 corresponds to the transport control applied to the transport device 464 shown in Figure 10. The print control program 522 corresponds to the print control applied to the print device 406. The print control program 522 includes a program for manufacturing the gradation correction chart 102 shown in Figure 6.

[0195] The measurement control program 524 corresponds to the measurement control applied to the measuring device 410. The drying control program 526 corresponds to the drying control applied to the drying device 412. The gradation correction data generation program 528 corresponds to the generation of correction data applied to the gradation correction process and the gradation correction process itself.

[0196] The various programs stored in the computer-readable medium 504 include one or more instructions. The computer-readable medium 504 stores various data and various parameters. Note that the memory 474 shown in Figure 10 is included in the computer-readable medium 504 shown in Figure 11.

[0197] The computer-readable medium 504 may function as a first memory device in which the gradation correction data generation program 528 is stored. The computer-readable medium 504 may function as a second memory device in which the transport control program 520, the print control program 522, and the drying control program 526 are stored. The computer-readable medium 504 may function as a third memory device in which the measurement control program 524 is stored.

[0198] The inkjet printing system 400 implements various functions by having the processor 502 execute various programs stored in the computer-readable medium 504. The term "program" is synonymous with the term "software."

[0199] The control device 500 performs data communication with an external device via the communication interface 506. The communication interface 506 can utilize various standards such as USB (Universal Serial Bus). The communication mode of the communication interface 506 may be either wired communication or wireless communication.

[0200] The control device 500 is connected to an input device 512 and a display device 514 via an input / output interface 508. Input devices such as a keyboard and mouse can be used as input devices for the input device 512. The display device 514 displays various information applicable to the control device 500.

[0201] The display device 514 can be a liquid crystal display, an organic EL display, a projector, etc. The display device 514 can be any combination of multiple devices. Note that EL in organic EL display is an abbreviation for Electro-Luminescence. The display device 514 shown in Figure 11 corresponds to the display device 16 shown in Figure 1.

[0202] Here, examples of the hardware structure of processor 502 include CPU, GPU, PLD (Programmable Logic Device), and ASIC (Application Specific Integrated Circuit). A CPU is a general-purpose processor that executes programs and acts as various functional units. A GPU is a processor specialized for image processing.

[0203] A PLD is a processor whose electrical circuit configuration can be changed after the device has been manufactured. An example of a PLD is an FPGA (Field Programmable Gate Array). An ASIC is a processor that has dedicated electrical circuits designed specifically to perform a particular task.

[0204] A single processing unit may be composed of one of these various processors, or it may be composed of two or more processors of the same or different type. Examples of various processor combinations include a combination of one or more FPGAs and one or more CPUs, and a combination of one or more FPGAs and one or more GPUs. Another example of various processor combinations is a combination of one or more CPUs and one or more GPUs.

[0205] A single processor can be used to configure multiple functional units. An example of configuring multiple functional units using a single processor is to configure a single processor by applying a combination of one or more CPUs and software, such as a System on a Chip (SoC), which is representative of a computer such as a client or server, and then having this processor function as multiple functional units.

[0206] Another example of using a single processor to configure multiple functional units is the use of a single IC chip to implement the functions of an entire system, including multiple functional units. IC stands for Integrated Circuit.

[0207] Thus, each functional unit is configured using one or more of the aforementioned processors as its hardware structure. More specifically, the hardware structure of these various processors is an electrical circuit formed by combining circuit elements such as semiconductor elements.

[0208] The computer-readable medium 504 may include semiconductor elements such as ROM (Read Only Memory) and RAM (Random Access Memory). The computer-readable medium 504 may include magnetic storage media such as hard disks. The computer-readable medium 504 may comprise multiple types of storage media.

[0209] [Chart manufacturing method according to the first embodiment] Figure 12 is a flowchart showing the procedure of the chart manufacturing method according to the first embodiment. Figure 12 shows each step and procedure applied to the gradation correction chart printing process S12 shown in Figure 3. Figure 12 shows the procedure when the inkjet printing system 400 shown in Figure 9 is applied as the printer 14 shown in Figure 1.

[0210] In the chart data acquisition step S100, the print control unit 466 shown in Figure 10 acquires the gradation correction chart data to be applied when printing the gradation correction chart 102 shown in Figure 5. After the chart data acquisition step S100, the process proceeds to the color conversion step S102.

[0211] In the color conversion step S102, the print control unit 466 converts the gradation correction chart data into gradation correction chart data represented using ink colors. If the gradation correction chart data is represented using ink colors, the color conversion step S102 is omitted. After the color conversion step S102, the process proceeds to the color separation step S104.

[0212] In the color separation process S104, the print control unit 466 separates the gradation correction chart data, which is represented using ink colors, to generate gradation correction chart data for each ink color. After the color separation process S104, the process proceeds to the halftone processing process S106.

[0213] In the halftone processing step S106, the print control unit 466 applies halftone processing to each of the gradation correction chart data for each ink color to generate a halftone image of the gradation correction chart for each ink color. After the halftone processing step S106, the process proceeds to the drive voltage generation step S107.

[0214] In the drive voltage generation process S107, the print control unit 466 generates a drive voltage for each ink color based on the halftone image of the gradation correction chart for each ink color. In other words, the drive voltage generation process S107 generates a drive voltage for each inkjet head. S107 The process then proceeds to the CMY patch printing step S108.

[0215] In the CMY patch printing process S108, the print control unit 466 prints the cyan patch group 112C using the inkjet head 420C shown in Figure 9. In the same process, the print control unit 466 also prints the magenta patch group 112M using the inkjet head 420M and the yellow patch group 112Y using the inkjet head 420Y.

[0216] In the black printing process S110, the print control unit 466 uses the inkjet head 420K to print the first measurement start position mark 106, the process color patch group 112, and the black measurement background image 130.

[0217] In the white patch printing process S112, the print control unit 466 uses the inkjet head 420W to print the second measurement start position mark 108, the first white patch group 120, and the second white patch group 122.

[0218] The CMY patch printing process S108, the black printing process S110, and the white patch printing process S112 are performed at the timing when the substrate 401 passes through the inkjet heads of each color. After the processes shown in Figure 12 have been completed and the gradation correction chart 102 shown in Figure 5 has been printed, the gradation correction data generation method shown in Figure 3 transitions from the gradation correction chart printing process S12 to the gradation correction chart measurement process S14.

[0219] The order of the CMY patch printing process S108 and the black printing process S110 may be reversed depending on the arrangement of the inkjet heads for each color. For example, if the inkjet heads for each color are arranged in the order of black, cyan, magenta, yellow, and white from the upstream side in the substrate transport direction, the CMY patch printing process S108 is performed after the black printing process S110.

[0220] [Specific examples of charts for tone correction] Figure 13 is a schematic cross-sectional view showing a gradation correction chart manufactured by applying the chart manufacturing method according to the first embodiment. The figure shows a cross-sectional view of the position where the second white patch group 122 and the black measurement background image 130 are printed on the gradation correction chart 102 shown in Figure 5. Figure 13 also illustrates the measurement direction of the gradation correction chart 102.

[0221] The gradation correction chart 102 shown in Figure 13 has a black measurement background image 130 printed on the printed surface 401A of the substrate 401, and a second group of white patches 122 printed over the black measurement background image 130.

[0222] [Effects and Effects of the Chart Manufacturing Apparatus and Chart Manufacturing Method According to the First Embodiment] The chart manufacturing apparatus and chart manufacturing method according to the first embodiment can achieve the following effects.

[0223] [1] In the gradation correction chart 102 on which the first white patch group 120 and the second white patch group 122 are printed, a black measurement background image 130, which serves as the background for the second white patch group 122, is printed. This allows for the measurement of the first white patch group 120 and the second white patch group 122, which use two different colored backgrounds, using only the white background 202, without switching from the white background 202 to the black background.

[0224] [2] The gradation correction chart 102 is measured using a white background 202. This eliminates the need for high-precision alignment between the first white patch group 120 and the second white patch group 122 and the white background 202.

[0225] [Chart manufacturing apparatus according to the second embodiment] Figure 14 is a configuration diagram showing an example of the configuration of a printing apparatus applied to the chart manufacturing apparatus according to the second embodiment. The printing apparatus 406A shown in the figure has an inkjet head 420CL added to the printing apparatus 406 shown in Figure 9.

[0226] The inkjet head 420CL is positioned between the inkjet heads 420K and 420W. Clear ink is applied to the inkjet head 420CL.

[0227] An example of clear ink is ink from which colorant-related components have been removed from process ink. Clear ink may sometimes be referred to as transparent ink. Here, "transparent" does not mean that the transmittance of visible light is less than 100 percent. The transmittance of the clear ink does not need to be such that it reduces the visibility of the white and black inks printed on top of it to a certain extent.

[0228] Figure 15 is a schematic cross-sectional view showing a chart manufactured using the chart manufacturing apparatus according to the second embodiment. In the grayscale correction chart 102A shown in the figure, a clear ink image 140 is printed over a black measurement background image 130, and then a second group of white patches 122 is printed over the clear ink image 140.

[0229] The clear ink image 140 may be printed over the entire surface of the black measurement background image 130, or it may be printed only between the black measurement background image 130 and the second white patch group 122.

[0230] [Chart manufacturing method according to the second embodiment] Figure 15 shows the chart manufacturing method according to the second embodiment, in which a clear ink image printing step is performed after the black printing step S110 shown in Figure 12, in which a clear ink image is printed. Furthermore, a white patch printing step S112 is performed after the clear ink image printing step.

[0231] [Effects and Effects of the Chart Manufacturing Apparatus and Chart Manufacturing Method According to the Second Embodiment] The chart manufacturing apparatus and chart manufacturing method according to the second embodiment can obtain the same effects and advantages as the first embodiment. In addition, a clear ink image 140 is printed between the second white patch group 122 to which white ink is applied and the black measurement background image 130 to which black ink is applied.

[0232] This suppresses the mixing of white ink and black ink, and reduces light scattering caused by the mixing of white ink and black ink at the interface between the two inks, making it possible to print a gradation correction chart 102A with relatively high contrast.

[0233] Note that the clear ink described in the embodiment is an example of a transparent coloring material. The clear ink image 140 described in the embodiment is an example of a transparent image.

[0234] [Chart manufacturing apparatus according to the third embodiment] Figure 16 is a schematic cross-sectional view showing a chart manufactured by applying the chart manufacturing apparatus and chart manufacturing method according to the third embodiment. In the grayscale correction chart 102B shown in the figure, a second group of white patches 122 is printed on the printing surface 401A, which is one side of the substrate 401.

[0235] Furthermore, a black measurement background image 130 is printed on the other side of the substrate 401, which is the back surface 401B. The black measurement background image 130 is printed in the area on the back surface 401B that corresponds to the area on the printed surface 401A of the substrate 401 where the second group of white patches 122 is printed.

[0236] The chart manufacturing apparatus according to the third embodiment is a double-sided printing apparatus that prints on both sides of the substrate 401. The double-sided printing apparatus includes a substrate inversion mechanism that inverts the printed side 401A and the back side 401B of the substrate 401.

[0237] [Chart manufacturing method according to the third embodiment] In the chart manufacturing method according to the third embodiment, instead of the CMY patch printing process S108 shown in Figure 12, a process is performed in which a cyan patch group 112C, a magenta patch group 112M, a yellow patch group 112Y, and a black patch group 112K are printed.

[0238] The black printing process S110 is omitted, and the white patch printing process S112 is performed. Subsequently, a substrate inversion process is performed, and after the substrate inversion process, a process is performed in which the black measurement background image 130 is printed.

[0239] In the chart manufacturing method according to the third embodiment, a substrate inversion step may be performed after the step of printing the black measurement background image 130 has been performed, and a CMY patch printing step S108 and a white patch printing step S112 may be performed after the substrate inversion step has been performed.

[0240] [Effects and Effects of the Chart Manufacturing Apparatus and Chart Manufacturing Method According to the Third Embodiment] The chart manufacturing apparatus and chart manufacturing method according to the third embodiment can obtain the same effects as the first and second embodiments. Furthermore, the decrease in contrast of the second white patch group 122 is suppressed. In addition, the amount of white ink applied to the second white patch group 122 and the amount of black ink applied to the black measurement background image 130 can be relatively increased.

[0241] [Chart manufacturing apparatus and chart manufacturing method according to the fourth embodiment] Figure 17 is a schematic cross-sectional view showing a chart manufactured using the chart manufacturing apparatus according to the fourth embodiment. The chart manufacturing apparatus according to the fourth embodiment is the inkjet printing system 400 shown in Figures 9 and 10. The chart manufacturing method according to the fourth embodiment is the flowchart shown in Figure 12.

[0242] In the gradation correction chart 102C shown in Figure 17, the black measurement background image 130 is printed on the printed surface 401A of the substrate 401, in the area 401D opposite the second white patch group 122, with the fold line 401C in between. The black measurement background image 130 may also be printed on the back surface 401B of the substrate 401.

[0243] Figure 18 is a schematic diagram showing the measurement state of the chart shown in Figure 17. As shown in Figure 18, the black measurement background image 130 is printed in a position that overlaps with the second white patch group 122 when the substrate 401 is folded back at the folding line 401C.

[0244] [Effects of the chart manufacturing apparatus and chart manufacturing method according to the fourth embodiment] The chart manufacturing apparatus and chart manufacturing method according to the fourth embodiment is an apparatus capable of printing only on the printing surface 401A of the substrate 401. and methods Therefore, even if the black measurement background image 130 and the second white patch group 122 cannot be printed on top of each other, the second white patch group 122 and the black measurement background image 130 can be printed on the printing surface 401A of the substrate 401.

[0245] [Variations of the chart for tone correction] In the gradation correction chart 102, etc., the first white patch group 120 may be left unprinted. This embodiment applies when white ink patches are measured using only a black background, and patches of inks other than white are measured using a white background.

[0246] Furthermore, in the gradation correction chart 102, etc., color patch groups other than the first white patch group 120 and the second white patch group 122, such as the cyan patch group 112C, may be left unprinted.

[0247] The gradation correction chart 102, etc., may have a white measurement background image printed on it that functions as a white background. For example, a white measurement background image that is a different color from the black measurement background image 130 may be printed using white ink on the entire surface of the substrate 100, the non-printed area of ​​the black measurement background image 130 of the substrate 100, and the printed area of ​​the first white patch group 120.

[0248] According to this embodiment, there is no need to form a white background 202 on the stage 201 that supports the grayscale correction chart 102. Furthermore, even if the white background 202 becomes dirty or damaged, measurements can be performed in a way that suppresses the effects of the dirt on the white background 202. Note that the white measurement background image described in the embodiment is an example of a second measurement background image.

[0249] [Differences in background] The opacity rate applied to ink management is an indicator that represents how well the underlying layer and the substrate can be printed without the ink showing through when the substrate is covered with ink. The two different colored backgrounds used in the measurement to derive the opacity rate are not limited to a white background and a black background.

[0250] For a white background, a color similar to the ink color may be used instead of white. For a black background, the color of the substrate or the color of the support surface supporting the substrate may be used instead of black.

[0251] To derive the opacity rate of white ink printed on a transparent substrate, the first white patch group 120 shown in Figure 5 is measured against a background of the same color as the white ink applied to it. The second white patch group 122 is then measured against a black background, which is susceptible to the watermark of the background color. Based on the measurement results for the first and second white patch groups 122, the extent to which the white ink blocks the background color is derived.

[0252] As an example of ink for which it is confirmed how much the background color is blocked, cyan ink can be cited when printing an image such as a logo character using cyan ink on a substrate with a red surface color. As another example, cyan ink can be cited when a printed matter obtained by printing an image such as a logo character using cyan ink on a transparent substrate is attached to a support plate with a red surface color.

[0253] In the above example, when the color of the background is opaque and the color of the logo character is not printed, the visibility of the logo character decreases, degrading the quality of the printed matter. In the above example, a background of cyan ink or a background of the same color as cyan ink is applied to measure the cyan ink patch, and a background of red, which is the color of the substrate, or a background of the same color as red is applied to measure the cyan ink patch.

[0254] From the measurement result Y1 obtained by applying a background such as cyan ink and the measurement result Y2 obtained by applying a background such as red, Y2 / Y1 is derived as the hiding power, and the concentration of cyan ink is controlled so that the hiding power Y2 / Y1 becomes a value of a certain level or more.

[0255] Here, cyan ink and red have been cited as examples for explanation, but the same applies to process inks such as magenta ink and spot inks such as green ink. That is, for any ink color, as the first background color corresponding to a black background, the color of the base material of the substrate, the same color as the color of the base material of the substrate, the color of the support surface supporting the substrate, or the same color as the color of the support surface supporting the substrate can be used, and as the second background color corresponding to a white background, the ink color or the same color as the ink color can be applied.

[0256] [Coverage rate of the measurement background image] When the ink coverage rate of the measurement background image is relatively low, the effect corresponding to the background color weakens, so the measurement background image requires a relatively high ink coverage rate. In the case of inkjet printing, the ink coverage rate does not reach 100 percent due to a slight deviation in the dot formation position.

[0257] Therefore, the measurement background image is less than 100 percent, and an ink coverage rate of a certain level or higher is allowed. For example, the ink coverage rate of the measurement background image can be 85 percent or higher. Note that the measurement background image is a general term for the black measurement background image 130 and the white measurement background image.

[0258] [Application Example to an Image Forming System] In the present embodiment, as an example of an image forming system, an inkjet printing system 400 including an inkjet printing device 406 is illustrated. However, the gradation correction data according to the embodiment can also be applied to an image forming system other than the inkjet method, such as an image forming system including an electrophotographic image forming device.

[0259] [Regarding Images] Images are interpreted in a broad sense and may include color images, black-and-white images, single-color images, gradation images, uniform density and solid images, etc. Images are used as a comprehensive term including not only photographic images but also patterns, characters, symbols, line drawings, mosaic patterns, color painting patterns, and other various patterns. Images may include the above appropriate combinations.

[0260] [Printing of Images] The printing of images may include concepts of terms such as formation, recording, printing, drawing, and printing of images.

[0261] The embodiments of the present invention described above can be appropriately modified, added, or deleted without departing from the spirit of the present invention. The present invention is not limited to the embodiments described above, and many modifications are possible by those with ordinary knowledge in the art within the technical idea of the present invention.

Explanation of Reference Numerals

[0262] 10 Gradation Correction Data Generation Device<C 12 Measuring Instrument 14 Printer 16 Display Device 16A Printer Operation Screen 20 Image Data Storage Unit 22 Printer Control Unit 24 Measuring Instrument Control Unit 26. Tone Correction LUT Generation Unit 28 LUT storage section 30 Correction Processing Unit 31 Tone Correction Processing Unit 52. In-plane unevenness correction processing unit 54 Non-discharge correction processing unit 60 straight line 62 curve 64 curve 66 curve 100 Base material 102-Color Correction Chart 102A Chart for tone correction 102B Chart for tone correction 102C Chart for Tone Correction 106 First measurement start position mark 108 Second measurement start position mark 110 Patch 110C Cyan Patch 110K Black Patch 110M Magenta Patch 110Y Yellow Patch 112 Process Color Patches 112C Cyan Patch Group 112K Black Patches 112M Magenta Patch Group 112Y Yellow Patch Group 114 Special Patches 114G Green Patch 114O Orange Patch 114V Violet Patch 120 First White Patch Group 122 Second White Patch Group 124 First White Patch 126 Second White Patch 130 Black Measurement Background Image 140 Clear Ink Images 201 Stages 201A Base material support surface 202 White background 300 Driving waveform 302 Discharge driving pulse 304 Discharge driving pulse 306 Discharge driving pulse 308 Discharge driving pulse 310 Discharge driving pulse 312 Discharge driving pulse 314 Reverberation suppression waveform element 400 Inkjet printing system 401 Substrate 401A Printing surface 401B Back surface 401C Fold line 401D Region 402 Substrate supply device 404 First intermediate conveyance device 406 Printing device 406A Printing device 408 Second intermediate conveyance device 410 Measuring device 412 Drying device 414 Integration device 420C Inkjet head 420CL Inkjet head 420K Inkjet head 420M Inkjet head 420W Inkjet head 420Y Inkjet head 422 Printing drum 430 Density measuring instrument 432 Reading conveyance roller 434 Stage 460 System control unit 462 Conveyance control unit 464 Conveyance device 466 Printing control unit 468 Measurement control unit 470 Drying control unit 472 Information acquisition unit 474 Memory 476 Sensor 500 Control device 502 Processors 504 Computer-readable media 506 Communication Interface 508 Input / Output Interfaces 510 Bus 512 Input device 514 Display device 520 Transport Control Program 522 Print control program 524 Measurement and Control Program 526 Drying control program 528-level tone correction data generation program S10~S18 Steps in the Tone Correction LUT Generation Method Steps S100-S112 in the gradation correction chart printing process

Claims

1. An image forming apparatus for forming a chart on a transparent substrate, which is measured by applying a first background color and a second background color that are different in color from each other, Processor and A storage device in which a program executed using the aforementioned processor is stored, A chart manufacturing apparatus comprising, The processor executes the instructions of the program, A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a first-color coloring material in which white is used. A chart manufacturing apparatus that forms a group of second patches, each containing one or more second patches using a coloring agent of a second color different from the first color, at a position on the transparent substrate where the first measurement background image is not formed.

2. The chart manufacturing apparatus according to claim 1, wherein the second background color used on the surface supporting the transparent substrate is a different color from the second color.

3. The chart manufacturing apparatus according to claim 1 or 2, wherein the first background color is a different color from the first color.

4. The chart manufacturing apparatus according to any one of claims 1 to 3, wherein the second background color is the same color as the first color.

5. The aforementioned processor, The first measurement background image is formed on one side of the transparent substrate. A chart manufacturing apparatus according to any one of claims 1 to 4, wherein the first patch group is formed by superimposing it onto the first measurement background image.

6. The aforementioned processor, A transparent image to which a transparent coloring material is applied is superimposed onto the first measurement background image to form a transparent image. A chart manufacturing apparatus according to any one of claims 1 to 5, wherein the first group of patches is superimposed on the transparent image to form the chart.

7. An image forming apparatus for forming a chart on a transparent substrate in which measurements are taken by applying a first background color and a second background color that are different in color from each other, Processor and A storage device in which a program executed using the aforementioned processor is stored, A chart manufacturing apparatus comprising, The processor executes the instructions of the program, A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a coloring agent of the first color. A second patch group, which includes one or more second patches, is formed in the transparent substrate at a location where the first measurement background image is not formed. A transparent image to which a transparent coloring material is applied is superimposed onto the first measurement background image to form a transparent image. A chart manufacturing apparatus for forming the first patch group by superimposing it onto the transparent image.

8. The aforementioned processor, The first group of patches is formed on one side of the transparent substrate. A chart manufacturing apparatus according to any one of claims 1 to 4, which forms the first measurement background image on the other surface of the transparent substrate corresponding to the position of the first patch group.

9. The aforementioned processor, The first group of patches is formed on one side of the transparent substrate. The chart manufacturing apparatus according to any one of claims 1 to 4, wherein the first measurement background image is formed at a position that overlaps with the first patch group when the transparent substrate is folded along the fold line.

10. An image forming apparatus for forming a chart on a transparent substrate, which is measured by applying a first background color and a second background color that are different in color from each other, Processor and A storage device in which a program executed using the aforementioned processor is stored, A chart manufacturing apparatus comprising, The processor executes the instructions of the program, A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a coloring agent of the first color. A second patch group, which includes one or more second patches, is formed in the transparent substrate at a location where the first measurement background image is not formed. The first group of patches is formed on one side of the transparent substrate. A chart manufacturing apparatus that forms the first measurement background image at a position that overlaps with the first patch group when the transparent substrate is folded back along the fold line.

11. The chart manufacturing apparatus according to any one of claims 1 to 10, wherein the processor forms the second patch group which includes one or more second patches formed using the first coloring agent.

12. The chart manufacturing apparatus according to any one of claims 1 to 11, wherein the processor uses a black coloring agent as a coloring agent corresponding to the first background color to form the first measurement background image.

13. The chart manufacturing apparatus according to any one of claims 1 to 6, wherein the processor uses at least one process color colorant as the second colorant to form one or more of the second patches.

14. The chart manufacturing apparatus according to any one of claims 1 to 13, wherein the processor forms a second measurement background image at a position corresponding to the position of the second patch group using a coloring agent of a color corresponding to the second background color.

15. The chart manufacturing apparatus according to claim 14, wherein the processor uses a white coloring agent as a coloring agent corresponding to the second background color to form the second measurement background image.

16. The chart manufacturing apparatus according to claim 14 or 15, wherein the processor forms the second measurement background image having a coverage rate of 85 percent or more.

17. The chart manufacturing apparatus according to any one of claims 1 to 16, wherein the processor forms the first measurement background image having a coverage rate of 85 percent or more.

18. The chart manufacturing apparatus according to any one of claims 1 to 17, wherein the processor forms the second patch to which the same grayscale value as the first patch is applied.

19. The aforementioned processor, A group of first patches, each having different grayscale values, are arranged along the transport direction of the transparent substrate to form the first patch group. A chart manufacturing apparatus according to any one of claims 1 to 18, wherein a group of second patches of the same color but with different gradation values ​​are arranged along the transport direction of the transparent substrate to form the second patch group.

20. A chart manufacturing method for forming a chart on a transparent substrate, in which a chart is measured by applying a first background color and a second background color that are different in color from each other, Computers A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a first-color coloring material in which white is used. A chart manufacturing method for forming a second patch group containing one or more second patches using a second colorant different from the first color at a position on the transparent substrate where the first measurement background image is not formed.

21. A method for manufacturing a chart, wherein a chart is formed on a transparent substrate by applying a first background color and a second background color that are different in color from each other, Computers A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a coloring agent of the first color. A second patch group, which includes one or more second patches, is formed in the transparent substrate at a location where the first measurement background image is not formed. A transparent image to which a transparent coloring material is applied is superimposed onto the first measurement background image to form a transparent image. A method for manufacturing a chart, comprising superimposing the first group of patches onto the transparent image.

22. A method for manufacturing a chart, wherein a chart is formed on a transparent substrate by applying a first background color and a second background color that are different in color from each other, Computers A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a coloring agent of the first color. A second patch group, which includes one or more second patches, is formed in the transparent substrate at a location where the first measurement background image is not formed. The first group of patches is formed on one side of the transparent substrate. A chart manufacturing method in which the first measurement background image is formed at a position that overlaps with the first patch group when the transparent substrate is folded back along the fold line.

23. A program for producing a chart that is measured by applying a first background color and a second background color that are different in color from each other, On the computer, A function to form a first measurement background image on a transparent substrate using a coloring agent corresponding to the first background color. The function of forming a group of first patches, which includes one or more first patches, at a position on the transparent substrate corresponding to the first measurement background image, using a first-color coloring material in which white is used, and A program that enables the formation of a second patch group containing one or more second patches using a second coloring agent different from the first color at a position on the transparent substrate where the first measurement background image is not formed.

24. A program for producing a chart that is measured by applying a first background color and a second background color that are different in color from each other, On the computer, A function to form a first measurement background image on a transparent substrate using a coloring agent corresponding to the first background color. A function to form a group of first patches, each containing one or more first patches, at a position on the transparent substrate corresponding to the first measurement background image, using a coloring agent of a first color. The function of forming a second patch group, which includes one or more second patches, at a location on the transparent substrate where the first measurement background image is not formed. A function for forming a transparent image to which a transparent coloring material is applied by superimposing it onto the first measurement background image, and A program that enables the function of superimposing the first group of patches onto the transparent image.

25. A program for producing a chart that is measured by applying a first background color and a second background color that are different in color from each other, On the computer, A function to form a first measurement background image on a transparent substrate using a coloring agent corresponding to the first background color. A function to form a group of first patches, each containing one or more first patches, at a position on the transparent substrate corresponding to the first measurement background image, using a coloring agent of a first color. The function of forming a second patch group, which includes one or more second patches, at a location on the transparent substrate where the first measurement background image is not formed. The function of forming the first patch group on one side of the transparent substrate, and A program that enables the formation of the first measurement background image at a position that overlaps with the first patch group when the transparent substrate is folded along the fold line.

26. A non-temporary and computer-readable recording medium on which a program according to any one of claims 23 to 25 is recorded.

27. An image forming apparatus for forming a chart on a transparent substrate, which is measured by applying a first background color and a second background color that are different in color from each other, Processor and A storage device in which a program executed using the aforementioned processor is stored, Equipped with, The processor executes the instructions of the program, A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a first-color coloring material in which white is used. An image forming system that forms a second patch group containing one or more second patches using a coloring agent of a second color different from the first color at a position on the transparent substrate where the first measurement background image is not formed.

28. An image forming apparatus for forming a chart on a transparent substrate in which measurements are taken by applying a first background color and a second background color that are different in color from each other, Processor and A storage device in which a program executed using the aforementioned processor is stored, Equipped with, The processor executes the instructions of the program, A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a coloring agent of the first color. A second patch group, which includes one or more second patches, is formed in the transparent substrate at a location where the first measurement background image is not formed. A transparent image to which a transparent coloring material is applied is superimposed onto the first measurement background image to form a transparent image. An image forming system that superimposes the first group of patches onto the transparent image.

29. An image forming apparatus for forming a chart on a transparent substrate in which measurements are taken by applying a first background color and a second background color that are different in color from each other, Processor and A storage device in which a program executed using the aforementioned processor is stored, Equipped with, The processor executes the instructions of the program, A first measurement background image is formed on the transparent substrate using a coloring agent corresponding to the first background color. A group of first patches, each containing one or more first patches, is formed on the transparent substrate at a position corresponding to the first measurement background image using a coloring agent of the first color. A second patch group, which includes one or more second patches, is formed in the transparent substrate at a location where the first measurement background image is not formed. The first group of patches is formed on one side of the transparent substrate. An image forming system that forms the first measurement background image at a position that overlaps with the first patch group when the transparent substrate is folded back along the fold line.

Images