JP2005091267A - Quality control system for printed matter and apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a matching of color tones of not only a halftone section but also a highlight section and a shadow section, an advance approval from a customer for a printed matter by providing objective standards with the customer without showing proofs to the customer, and reproduction of the color tones approved by the customer in advance without showing the proofs or a printing sample to an operator. <P>SOLUTION: A gray balance measuring patch for a highlight section, a gray balance measuring patch for a halftone section, and a gray balance measuring patch for a shadow section are printed to the printed matter as gray balance measurement sections. The color values (an L-value, an a-value, and a b-value) of theses patches are measured, and a color difference ΔE, the differences of chromaticness indexes Δa, Δb, and the difference of lightness indexes ΔL are displayed in a QC bird's eye view compared with reference chromatic values (L-values, a-values, and b-values) of the highlight section, halftone section, and shadow section. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a print quality control method and apparatus using gray balance.

  Conventionally, the management of the color tone of a printed material is a solid patch (mesh) for each color actually printed on the printed material (sumi (black), cyan (eye), magenta (red), yellow (ki)). By measuring the density value of a patch with a dot area ratio of 100% with a colorimeter or densitometer, and adjusting the ink supply amount of the printing press so that the measured density value of each color becomes the reference density value of each color (See Patent Document 1).

  However, since most of the actual printed matter is halftone dots and not solid, changes in the printing environment, changes in printing materials, etc., or changes in dot gain or ink trapping due to differences in printing machines occur. However, even if the density values of the solid portions of the respective colors are the same, the tone of the halftone portion where the colors are mixed is not necessarily the same. Therefore, even if the ink supply amount of the printing press is adjusted so that the density value of the solid patch of each color becomes the reference density value, the color tone of the printed matter remains the same as that of the proofreader or DDCP (Direct Digital Color Proofer: Direct Digital Color Proofer). There was a problem that the color tone was different from the color tone of the proof printed by Proofer.

  For this reason, there is a problem that trouble occurs between the customer and the printing company as “the proof printed in advance is different from the actual printed matter”. In order to avoid such problems, recently, after adjusting the ink supply amount of each color so that the density value of the solid patch of each color becomes the reference density value, the same as the majority of many printed materials, A gray balance measurement patch in which three reference colors of cyan, magenta, and yellow (hereinafter referred to as reference three colors) are mixed is printed on a printed matter so that the tone of the gray balance measurement patch is the same as the sample. In addition, an operator has come to adjust the ink supply amount of the reference three colors.

JP 2002-86688 A

  However, in the past, the only gray balance measurement patch of the halftone portion was provided, and the ink supply amount of the reference three colors was adjusted only by the color tone of the only gray balance measurement patch of the halftone portion. Although the tone of the halftone portion can be adjusted, there has been a problem that the tone of the highlight portion having a small halftone dot area ratio of the three basic colors and the shadow portion having a large dot area ratio cannot be adjusted well. .

  Traditionally, prior confirmation of printed matter to a printing company customer shows the proof to the customer in advance, approves whether or not it is acceptable, and when printing the printed matter, the same color tone as the proof that received the approval. However, because the proof is approved only by the impression that the customer sees, even if the color of the proof and the printed material are the same, the proof and Customer impressions due to differences in the environment in which the printed material is actually viewed and the state of the customer itself (difference between what was seen before checking the physical condition and proof and what was seen before the actual printed material was seen) However, there is a problem that a trouble occurs between the customer and the printing company as “the proof printed in advance is different from the actual printed matter”.

The present invention has been made to solve such problems, and the object of the present invention is to provide a quality control method for printed matter that can match not only the halftone portion but also the color tone of the highlight portion and the shadow portion. And providing an apparatus.
In addition to the above-mentioned purpose, a quality control method for printed matter that allows the customer to obtain prior approval of the printed matter without providing a proof to the customer by setting an objective standard with the customer and To provide an apparatus.

  In order to achieve such an object, the present invention provides a highlight portion having a small dot area ratio of cyan, magenta and yellow, a shadow portion having a large dot area ratio of cyan, magenta and yellow, cyan, magenta and yellow. The halftone area ratio of yellow is larger than the highlight part and the halftone part smaller than the shadow part is printed on the printed matter as the gray balance measurement part, and the color values of the highlight part, halftone part and shadow part are measured, The quality of the printed matter is judged from the measured color values of the highlight portion, halftone portion and shadow portion.

In the present invention, as a gray balance measurement unit, a highlight part and a shadow part are printed on a printed matter in addition to a halftone part. For example, a gray balance measurement patch for a halftone portion, a gray balance measurement patch for a highlight portion, and a gray balance measurement patch for a shadow portion are printed on the margin of the printed material. Then, the color value of each gray balance measurement patch is measured with a colorimeter. As the color value, for example, it is defined by JISZ8729 of the Japanese Industrial Standard (JIS standard), and is represented by an L ^* a ^* b ^* color system which is a color display method recommended by the International Lighting Commission (CIE). “L ^* value, a ^* value, b ^* value” or “L ^* value, u ^* value, v ^* value” expressed in the L ^* u ^* v ^* color system can be used. Then, the quality of the printed matter is judged from the measured color values of the highlight portion, halftone portion and shadow portion. Based on the determination result, by adjusting the ink supply amounts of the three basic colors, it is possible to adjust the color tone of not only the halftone portion but also the highlight portion and the shadow portion.

[Adjustment of difference in chromaticness index]
For example, the chromaticness index (L ^* a ^* b ^* color system) of the highlight section in the color system is determined from the color value (measured value) of the highlight section and the reference color value of the highlight section ^. ”,“ B ^* ”, L ^* u ^* v ^* “ u ^* ”in the color system , "V ^* " ) Difference. Also, the difference in chromaticness index of the halftone part in the color system is obtained from the color value (measured value) of the halftone part and the reference color value of the halftone part, and the color value (measured value) of the shadow part and its The difference of the chromaticness index of the shadow part in the color system is obtained from the reference color value of the shadow part. The ink supply amounts of the three basic colors are adjusted so that the difference between the obtained chromaticness index of the highlight portion, halftone portion, and shadow portion is close to the target difference of the chromaticness index.

[Adjustment of brightness index difference]
For example, from the color value (measured value) of the highlight portion and the reference color value of the highlight portion, the brightness index (L ^* a ^* b ^* color system or L ^* u ^* v ^* ) of the highlight portion in the color system In other words, the difference of “L ^* ”) is obtained. Also, the difference in brightness index of the halftone part in the color system is obtained from the color value (measured value) of the halftone part and the reference color value of the halftone part, and the color value (measured value) of the shadow part and its shadow are obtained. The difference in brightness index of the shadow part in the color system is obtained from the reference color value of the part. The reference ink supply amounts of the three colors are adjusted so that the difference in brightness index between the obtained highlight part, halftone part, and shadow part approaches the target difference in brightness index.

(Adjust color difference)
For example, the color difference (L ^* a ^* b ^* color system in the color system (“ΔE ^* _ab ”) from the color value (measured value) of the highlight area and the reference color value of the highlight area. L ^* u ^* v ^{* In the} color system, “ΔE ^* _uv ” is obtained, and the halftone in the color system is obtained from the color value (measured value) of the halftone part and the reference color value of the halftone part. The color difference of the shadow part is obtained from the color value (measured value) of the shadow part and the reference color value of the shadow part, and the color difference of the shadow part in the color system is obtained. Adjust the ink supply amount of the three basic colors so that the color difference is close to the target color difference: ΔE ^* _ab or L ^* u ^* v ^* color system of L ^* a ^* b ^* color system ΔE ^* _uv is specified in JISZ8730 of the Japanese Industrial Standard (JIS standard). According to this rule, ΔE ^* _ab is determined as ΔE ^* _ab = [(ΔL ^* ) ² + (Δa ^* ) ² + (Δb ^* ) ² )] ^1/2 , and ΔE ^* _uv is ΔE ^* _Uv = [(ΔL ^* ) ² + (Δu ^* ) ² + (Δv ^* ) ² )] ^1/2 )

  In the present invention, the reference color value of the highlight portion is the color value of one of the gray color charts of the Munsell color system having a relatively high brightness index (for example, N8), and the reference color value of the shadow portion is Munsell. The color value of one of the gray color charts of the color system with a relatively small brightness index (for example, N4) is used, and the reference color value of the halftone portion is a highlight of the gray color chart of the Munsell color system. One (for example, N6) color value is smaller than the lightness index of the reference color value of the portion and larger than the lightness index of the reference color value of the shadow portion. In the Munsell color solid, the central axis is the achromatic color axis, and there are 10 steps (N0 to N10) on a constant rate scale. In this achromatic axis, N0 is “black”, N10 is “white”, and in the meantime, it becomes “gray” which becomes darker from N0 toward N10. N0 to N10 are gray color charts of the Munsell color system and are called lightness indexes. N4 is a relatively dark gray, N8 is a relatively light gray, and N6 is a lighter gray than N4 and a darker gray than N8.

  When printing the gray balance measurement part (highlight part, halftone part, shadow part) on printed matter, one of the color values of the highlight part with a relatively high brightness index among the Munsell color system gray color charts The halftone dot area ratios of cyan, magenta, and yellow in the highlight portion are determined so that the color value is close to the color value (for example, N8), and the color value in the shadow portion is the one of the Munsell color system gray color chart The halftone dot area ratio of cyan, magenta, and yellow in the shadow portion is determined so that the color value is near one of the color values having a relatively small brightness index (for example, N4), and the color value in the halftone portion is the Munsell table. Colors in the vicinity of the color value of one of the gray color charts of the color system that are smaller than the lightness index of the reference color value of the highlight portion and larger than the lightness index of the reference color value of the shadow portion (for example, N6) So as to define cyan halftone area, the halftone dot area ratio of magenta and yellow.

(Chromaticness index difference, brightness index difference, color difference display)
In the present invention, the quality of the printed matter from the measured color values of the highlight portion, the halftone portion, and the shadow portion may be automatically determined by the apparatus. . In this case, by displaying “difference in chromaticness index”, “difference in lightness index”, and “color difference” on the graph, the operator can easily judge the quality of the printed matter. For example, the color difference in the highlight part, the color difference in the halftone part, and the color difference in the shadow part are displayed in a line graph, and the difference in the chromaticness index in the highlight part, the difference in the chromaticness index in the halftone part, and the chromaticness in the shadow part. The difference in the exponent is displayed on the two-dimensional color coordinates, and the difference in the brightness index in the highlight portion, the difference in the brightness index in the halftone portion, and the difference in the brightness index in the shadow portion are displayed in a line graph.

In addition, a display unit (for example, a hue) is displayed outside a two-dimensional color coordinate that displays a difference in chromaticness index in a highlight portion, a difference in chromaticness index in a halftone portion, and a difference in chromaticness index in a shadow portion. If a (hue ring) is provided, the display becomes intuitive and easy to understand. In addition, a display section (gray light and dark band) representing brightness is provided beside the line graph displaying the difference in brightness index in the highlight area, the difference in brightness index in the halftone area, and the difference in brightness index in the shadow area. Intuitive and easy-to-understand display.
In addition, by showing the customer the graphs of “Chromaticness Index Difference”, “Brightness Index Difference”, and “Color Difference” of the printed material after the color tone of the highlight, halftone, and shadow areas are matched, Even without showing a proof, it is possible to obtain pre-approval of the printed matter from the customer.

According to the present invention, as the gray balance measurement unit, in addition to the halftone part, the highlight part and the shadow part are printed on the printed matter, and the color values of the highlight part, the halftone part and the shadow part are measured and measured. By judging the quality of the printed matter from the color values of the highlight part, the halftone part and the shadow part, not only the halftone part but also the highlight part and the shadow part can be matched.
In addition, as a difference from each reference color value of the highlight part, the halftone part and the shadow part, for example, `` difference in chromaticness index '', `` difference in lightness index '', `` color difference '' etc. are displayed on the graph, The operator can easily judge the quality of the printed matter, and an objective standard can be set with the customer so that the customer can obtain prior approval of the printed matter without showing the proof to the customer.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of a quality control apparatus for printed matter showing an embodiment of the present invention. In the figure, 1 is a main control device (hereinafter referred to as a main control device), 2 is a colorimeter control device (hereinafter referred to as color measurement) that controls a colorimeter (described later) under the control of the main control device 1. 3 is an ink supply amount control device for controlling the ink supply amount of the printing press under the control of the main control device 1, and 4 is a printing plate printing device.

  In the main controller 1, 1-1 is a CPU, 1-2 is a RAM, 1-3 is a ROM, 1-4 is an input device, 1-5 is a display, 1-6 is an output device such as a printer, 1- 7 to 1-9 are input / output interfaces (I / O, I / F), and 1-10 to 1-32 are memories. The CPU 1-1 obtains various input information given through the interfaces 1-7 to 1-9, and accesses the RAM 1-2 and the memories 1-10 to 1-32, and stores the programs stored in the ROM 1-3. Works according to.

  FIG. 2 shows the internal configuration of the colorimeter control device 2. In the colorimeter control device 2, 2-1 is a CPU, 2-2 is a RAM, 2-3 is a ROM, 2-4 is a colorimeter, 2-5 is a motor for moving the colorimeter, and 2-6 is a rotary. Encoder, 2-7 is a motor driver, 2-8 is a counter, 2-9 is an A / D converter, 2-10 to 2-12 are interfaces (I / O, I / F), 2-13, 2- Reference numeral 14 denotes a memory. The CPU 2-1 obtains various input information given through the interfaces 2-10 to 2-12 and accesses the RAM 2-2 and the memories 2-13 and 2-14 while storing the programs stored in the ROM 2-3. Works according to. The rotary encoder 2-6 generates a rotation pulse at every predetermined number of rotations (angle) of the colorimeter moving motor 2-5 and outputs the rotation pulse to the counter 2-8.

  In the colorimeter controller 2, the colorimeter 2-4 is attached to a ball screw (feed screw) 2-17 provided between the columns 2-15 and 2-16, as shown in FIG. The ball screw 2-17 is rotated forward / reversely by the colorimeter moving motor 2-5. By the forward / reverse rotation of the ball screw 2-17, the colorimeter 2-4 moves between the columns 2-15 and 2-16 while being guided by the ball screw 2-17. The head portion 2-4a of the colorimeter 2-4 is directed to the surface 2-18a on which the measurement target of the measurement table 2-18 is placed.

  FIG. 3 shows an internal configuration of the ink supply amount control device 3. In the ink supply amount control device 3, 3-1 is a CPU, 3-2 is a RAM, 3-3 is a ROM, 3-4 (3-41 to 3-4n) is an ink fountain key opening amount adjusting device, 3-5 (3 −51 to 3-5n) and 3-6 are interfaces (I / O, I / F), and 3-71 to 3-76 are memories. The CPU 3-1 obtains various input information given via the interfaces 3-51 to 3-5 n and 3-6 and accesses the ROM 3-3 while accessing the RAM 3-2 and the memories 3-71 to 3-76. Operates according to the stored program.

  The ink fountain key opening adjustment devices 3-41 to 3-4 n are provided for the respective ink fountain keys of the printing units for each color (in this embodiment, four colors of sumi, cyan, magenta, and yellow). The ink fountain key opening amount adjusting devices 3-41 to 3-4n adjust the opening amounts of the ink fountain keys arranged in parallel in the axial direction of the plate cylinder to the ink fountain rollers.

  The ink fountain key opening adjustment device 3-4 includes an ink fountain key motor 3-4A, an ink fountain key motor driver 3-4B, a rotary encoder 3-4C, and a counter 3-4D. The rotary encoder 3-4C generates a rotation pulse at every predetermined number of rotations of the ink fountain key motor 3-4A and outputs the rotation pulse to the counter 3-4D.

[Gray balance patch]
In the present embodiment, as a gray balance measurement unit, a highlight part and a shadow part are printed on a printed matter in addition to a halftone part. That is, as a gray balance measurement unit, a gray balance measurement patch PH of a highlight unit, a gray balance measurement patch PM of a halftone unit, and a gray balance measurement of a shadow unit as shown in FIG. The patch PS for printing is printed.

  The reference color value of the gray balance measurement patch PH in the highlight portion is the color value of one of the Munsell color system gray color charts having a relatively high brightness index (N8 in this example), and the shadow portion The reference color value of the gray balance measurement patch PS is the color value of one of the Munsell color system gray color charts having a relatively low brightness index (N4 in this example), and the gray balance measurement of the halftone portion The standard color value of the patch PM for the Munsell color system is one of the gray color charts of the Munsell color system which is smaller than the lightness index of the reference color value of the highlight portion and larger than the lightness index of the reference color value of the shadow portion (in this example, , N6).

  FIG. 6 shows an arrangement of lightness and saturation on the equi-hue surface of the Munsell color system. In the Munsell color solid, the central axis is the achromatic color axis, and there are 10 steps (N0 to N10) on a constant rate scale. In this achromatic axis, N0 is “black”, N10 is “white”, and in the meantime, it becomes “gray” that becomes darker from N10 toward N0. N0 to N10 are gray color charts of the Munsell color system and are called lightness indexes. N4 is a relatively dark gray, N8 is a relatively light gray, and N6 is a lighter gray than N4 and a darker gray than N8. In the present embodiment, the lightness index of the reference color value of the gray balance measurement patch PH in the highlight portion is N8, the lightness index of the reference color value of the gray balance measurement patch PM in the halftone portion is N6, and the gray color in the shadow portion. The lightness index of the reference color value of the balance measurement patch PS is N4.

  Then, the color values of the gray balance measurement patches PH, PM, PS actually printed on the printed matter are measured, and the differences between the color values of the gray balance measurement patches PH, PM, PS and the respective reference color values are obtained. The difference between the obtained gray balance measurement patches PH, PM, and PS and the reference color value is displayed in a QC bird's-eye view (FIG. 15) described later. The operator determines the quality of the printed matter based on the difference from the reference color values of the gray balance measurement patches PH, PM, and PS displayed in the bird's eye view of QC, and adjusts the ink supply amount of the reference three colors. To do. As a result, not only the halftone portion but also the color tone of the highlight portion and the shadow portion can be adjusted.

[Create patch for gray balance measurement]
In order to print the gray balance measurement patches PH, PM, PS on the printed matter, the halftone dot area ratio of each color of the gray balance measurement patches PH, PM, PS is determined, and the determined halftone dot area ratio of each color is determined. Therefore, it is necessary to make a printing plate for each color by printing the gray balance measurement patches PH, PM, and PS. In this embodiment, the gray balance measurement patch creation print 5 as shown in FIG. 7 is used to determine the halftone dot area ratio of each color of the gray balance measurement patches PH, PM, and PS.

  This gray balance measurement patch creation printed matter 5 is printed by a printing machine (not shown) to be managed. For example, a strip-shaped color chart 5-1 and a color bar 5-2 are provided on the holding side. It is printed. The color chart 5-1 and the color bar 5-2 may be printed on the bottom side of the printed material 5 or may be printed in the center of the printed material 5.

  The color chart 5-1 has 5%, 10% cyan, 10% magenta, 10% yellow, or 5%, 20% cyan, 10% magenta, and 20% yellow (sumi, cyan, (Magenta, yellow) is composed of a large number of patches 5a each having a different dot area ratio.

  The color bar 5-2 includes areas S1 to Sn including solid, cyan, magenta, and yellow solid patches (density measurement patches) 5b1, 5b2, 5b3, and 5b4. The regions S1 to Sn correspond to key zones of ink fountain keys arranged in parallel in the axial direction of the plate cylinder in the printing unit of each color in the printing press.

In this embodiment, the color value is defined by JISZ8729 of the Japanese Industrial Standard (JIS standard) and is a color display method recommended by the International Lighting Commission (CIE) L ^* a ^* b ^* color specification. “L ^* , a ^* , b ^* ” expressed in the system is used. Hereinafter, “L ^* ” is abbreviated as “L”, “a ^* ” as “a”, and “b ^* ” as “b”.

[Density adjustment before determining halftone dot area ratio of patch for gray balance measurement (Fig. 9)]
The printed matter 5 (FIG. 7) is printed by the printing machine. A color chart 5-1 and a color bar 5-2 are printed on the printed matter 5. The color chart 5-1 includes a large number of patches 5a in which the dot area ratio (%) of each color is determined in advance. The color bar 5-2 includes areas S1 to Sn including solid patches 5b (5b1, 5b2, 5b3, 5b4) of the respective colors.

  First, the operator sets the printed matter 5 immediately after printing by the printing machine on the measurement table 2-18 (FIG. 4) provided with the colorimeter 2-4 as a measurement target. In this set state, the color bar 5-2 printed on the printed matter 5 is located on the lower surface of the head portion 2-4a of the colorimeter 2-4.

  Next, the operator inputs a reference density value and an allowable density value for the solid patch 5b of each color of the color bar 5-2 from the input device 1-4 (step 101 shown in FIG. 9). Further, the position of the solid patch 5b of each color in the color bar 5-2 is input from the input device 1-4 (step 102). The CPU 1-1 stores the reference density value and the allowable density value for the solid patch 5b of each color of the input color bar 5-2 in the memories 1-10 and 1-11, and each color in the input color bar 5-2. The position of the solid patch 5b is stored in the memory 1-12. Then, the position (measurement position) of the solid patch 5b of each color to be measured by the colorimeter 2-4 is calculated, and the calculated measurement position is stored in the memory 1-26 (step 103).

  Next, the operator turns on a color bar measurement start switch (not shown) of the input device 1-4. When the start switch is turned on (YES in step 104), the CPU 1-1 transfers the position (measurement position) of the solid patch 5b of each color to be measured, stored in the memory 1-26, to the colorimeter controller 2. (Step 105).

  When the position of the solid patch 5b of each color to be measured is transferred from the main control device 1 (YES in step 201 shown in FIG. 10), the CPU 2-1 of the colorimeter control device 2 transfers the measurement that has been transferred. The position of the solid patch 5b for each color to be stored is stored in the memory 2-13 (step 202). Then, the colorimeter moving motor 2-5 is rotated forward (step 203).

  The ball screw 2-17 is rotated forward by the normal rotation of the colorimeter moving motor 2-5, and the column 2 is guided from the origin position where it is guided by the ball screw 2-17 and contacts the column 2-16. Move in the 15 direction. The CPU 2-1 monitors the moving position of the colorimeter 2-4 via the rotary encoder 2-6 (Step 204), and the colorimeter 2-4 is the first stored in the memory 2-13. When the measurement position is reached, the color data of the solid patch 5b located at the measurement position is collected by the colorimeter 2-4 (step 205). Then, the CPU 2-1 stores the color data (colorimetric data) from the colorimeter 2-4 in the memory 2-14 (step 206).

  Similarly, every time the CPU 2-1 reaches the measurement position stored in the memory 2-13, the color data of the solid patch 5b located at the measurement position is collected by the colorimeter 2-4. The color data is stored in the memory 2-14. That is, the CPU 2-1 collects the color data of the solid patches 5b of each color of the color bar 5-2 printed on the printed matter 5 one after another by automatically scanning the colorimeter 2-4.

  The CPU 2-1 determines whether or not the color data collection of all the solid patches 5b of the color bar 5-2 is completed (step 207), and the colorimeter moving motor 2-5 is rotated forward by the completion of the collection. Stop (step 208). Next, the CPU 2-1 reverses the colorimeter moving motor 2-5 (step 209), returns the colorimeter 2-4 to the origin position, and then moves the colorimeter moving motor 2-5. The reverse rotation is stopped (steps 210 and 211).

  Then, the CPU 2-1 transfers the color measurement data of the solid patches 5b of the respective colors in the areas S1 to Sn stored in the memory 2-14 to the main control device 1 (step 212). The transferred colorimetric data of the solid patches 5b of the respective colors in the areas S1 to Sn are stored in the memory 1-27 of the main control device 1 (steps 106 and 107). The CPU 1-1 of the main control device 1 calculates the density value of the solid patch 5b of each color of the regions S1 to Sn from the colorimetric data of the solid patch 5b of each color of the regions S1 to Sn from the colorimeter control device 2, and the memory 1 -14 (step 108).

  In the present embodiment, a spectrometer is used as the colorimeter 2-4, and the transmittance of each wavelength of the filter used when measuring the solid patch of each color with the densitometer is used as the output value of each wavelength from the spectrometer. By multiplying them and summing them, the density value of each color is obtained.

  Then, the CPU 1-1 reads the reference density value of the solid patch of each color from the memory 1-10 (step 109), and the measured density value of the solid patch 5b of each color and the reference density value of each color stored in the memory 1-14. Is calculated and stored in the memory 1-15 (step 110). Further, the absolute value of the difference between the measured density value of the solid patch 5b for each color stored in the memory 1-14 and the reference density value of the solid patch for each color is calculated and stored in the memory 1-16 (step 111).

  Next, the CPU 1-1 reads the allowable density value of the solid patch of each color from the memory 1-11 (step 112), and calculates the measured density value of the solid patch 5b of each color calculated in step 111 and the reference density value of the solid patch of each color. The absolute value of the difference is compared with the allowable density value of each color (step 113).

  The processing in steps 109 to 113 is performed for the solid patches 5b of the respective colors in the areas S1 to Sn of the color bar 5-2, and the absolute value of the difference between the measured density value and the reference density value in one of the areas S1 to Sn. If there is a solid patch 5b exceeding the allowable density value (NO in step 113), the difference between the measured density value of each color solid patch 5b exceeding the allowable density value and the reference density value is transferred to the ink supply amount control device 3 ( In step 114), the opening amount (ink supply amount) of the key points in the printing unit of the color corresponding to the solid patch 5b is controlled so that the absolute value of the difference becomes equal to or less than the allowable density value. Then, the printed material 5 is printed again by the printing machine in which the ink supply amount is controlled, and the printed material 5 immediately after printing is set on the measurement table 2-18 as a measurement object, and the operator turns on the color bar measurement start switch. (YES at step 104), the processing after step 105 is repeated.

  FIG. 11 shows a processing operation in the ink supply amount control device 3. The CPU 3-1 of the ink supply amount control device 3 transfers the difference between the measured density value and the reference density value of the solid patch 5b of each color exceeding the allowable density value from the main control device 1 (YES in step 301). The difference between the measured density value and the reference density value of the solid patch 5b of each color exceeding the transferred allowable density value is stored in the memory 3-71 (step 302).

  Then, the density difference-ink fountain key opening amount correction amount conversion table stored in the memory 3-72 is read (step 303). Based on the read density difference-ink fountain key opening amount correction amount conversion table, the memory The difference between the measured density value and the reference density value of the solid patch 5b of each color stored in 3-71 is converted into a correction value for the opening degree of the ink fountain key (step 304).

  Then, the CPU 3-1 reads the value of the ink fountain key position detection counter 3-4D of the ink fountain key opening amount adjusting device 3-4 for each ink fountain key of each color (step 305), and reads the read ink fountain key position counter 3 The current ink fountain key opening amount is calculated from the value of -4D (step 306). Then, a correction opening amount of the ink fountain key is obtained from the obtained opening amount of the ink fountain key and the correction value of the opening amount of the ink fountain key obtained in step 304 (step 307). Output (step 308).

[Determination of halftone dot area ratio of patch for gray balance measurement (FIG. 12)]
In step 113 shown in FIG. 9, if the absolute value of the difference between the measured density value of each color solid patch 5b and the reference density value is equal to or less than the allowable density value for all the areas S1 to Sn of the color bar 5-2. The process proceeds to the determination process of the dot area ratio of the gray balance measurement patch shown in FIG.

  In this gray balance measurement patch halftone dot area ratio determination process, the operator first positions the color chart 5-1 printed on the printed matter 5 on the lower surface of the head portion 2-4a of the colorimeter 2-4. Then, the printed product 5 is reset. Next, the operator inputs the position of each patch 5a in the color chart 5-1 and the dot area ratio of each color of each patch 5a from the input device 1-4 (step 115 shown in FIG. 12). The CPU 1-1 stores the position of each patch 5a in the input color chart 5-1 and the dot area ratio of each color of each patch 5a in the memory 1-24.

  The halftone dot area ratio of each color of each patch 5a to be input is determined in advance for each patch 5a, not a measured value from the printing plate on which each patch 5a is printed or the printed matter 5 actually printed. This is the value of each color. That is, when a printing plate of each color of the printed matter 5 is created, a value actually input to the printing plate printing apparatus 4 corresponding to each patch 5a is set as a set value, and this set value is a halftone dot area of each color of each patch 5a. The rate is entered in step 115.

Next, the operator inputs color values (L value, a value, b value) of N8, N6, and N4 of the Munsell color system gray color chart (step 116). The CPU 1-1 stores the input color values N8, N6, and N4 in the memory 1-25.
Then, the CPU 1-1 and the colorimeter 2-4 calculate the position (measurement position) of each patch 5a in the color chart 5-1 to be measured, and store the calculated measurement position in the memory 1-26 (step 117). ).

  Next, the operator turns on a color chart measurement start switch (not shown) of the input device 1-4. When the start switch is turned on (YES in step 118), the CPU 1-1 transfers the position (measurement position) of each patch 5a to be measured stored in the memory 1-26 to the colorimeter controller 2 ( Step 119).

  When the position of each patch 5a to be measured is transferred from the main controller 1 (YES in step 201 shown in FIG. 10), the CPU 2-1 of the colorimeter controller 2 measures the transferred measurement. The position of the patch 5a for each color to be stored is stored in the memory 2-13 (step 202). Then, the colorimeter moving motor 2-5 is rotated forward (step 203).

  The ball screw 2-17 is rotated forward by the normal rotation of the colorimeter moving motor 2-5, and the column 2 is guided from the origin position where it is guided by the ball screw 2-17 and contacts the column 2-16. Move in the 15 direction. The CPU 2-1 monitors the moving position of the colorimeter 2-4 via the rotary encoder 2-6 (Step 204), and the colorimeter 2-4 is the first stored in the memory 2-13. When the measurement position is reached, the color data of the patch 5a located at the measurement position is collected by the colorimeter 2-4 (step 205). Then, the CPU 2-1 stores the color data (colorimetric data) from the colorimeter 2-4 in the memory 2-14 (step 206).

  Similarly, every time the CPU 2-1 reaches the measurement position stored in the memory 2-13, the color data of the patch 5a located at the measurement position is collected by the colorimeter 2-4. Color data is stored in the memory 2-14. That is, the CPU 2-1 collects color data of each patch 5a of the color chart 5-1 printed on the printed matter 5 one after another by automatically scanning the colorimeter 2-4.

  The CPU 2-1 determines whether or not the color data collection for all the patches 5a in the color chart 5-1 is completed (step 207), and when the collection is completed, the colorimeter moving motor 2-5 is rotated forward. Stop (step 208). Next, the CPU 2-1 reverses the colorimeter moving motor 2-5 (step 209), returns the colorimeter 2-4 to the origin position, and then moves the colorimeter moving motor 2-5. The reverse rotation is stopped (steps 210 and 211).

  In the case where the color chart 5-1 is composed of three rows of bands as shown in FIG. 7, the operator places the color chart of each row on the lower surface of the head portion 2-4a of the colorimeter 2-4. While the printed product 5 is reset so as to be positioned, the color chart measurement start switch in step 118 is turned on three times, and the color data of the patches 5a of all the color charts 5-1 are collected.

  Then, the CPU 2-1 transfers the color measurement data of each patch 5a of the color chart 5-1 stored in the memory 2-14 to the main control device 1 (step 212). The transferred colorimetric data of each patch 5b of the color chart 5-1 is stored in the memory 1-27 of the main control device 1 (steps 120 and 121). The CPU 1-1 of the main control device 1 calculates the color value (L value, a value, b value) of each patch 5a from the color measurement data of each patch 5a of the color chart 5-1 from the colorimeter control device 2. And stored in the memory 1-28 (step 122).

  Next, the CPU 1-1 reads out the color values (L value, a value, b value) of N8, N6, and N4 of the Munsell color system gray color chart stored in the memory 1-25 (step 123). The position of the patch closest to the color value of N8 from the color value of each patch 5a of the color chart 5-1 obtained in step 122 is stored in the memory 1-29 (step 124). Further, the halftone dot area ratio of each color (cyan, magenta, yellow) of the patch is stored in the memory 1-30 as the halftone dot area ratio of each color of the gray balance measurement patch in the highlight portion (step 125).

  Further, the CPU 1-1 stores the position of the patch closest to the color value of N6 in the memory 1-29 from the color value of each patch 5a of the color chart 5-1 obtained in step 122 (step 126). Further, the halftone dot area ratio of each color (cyan, magenta, yellow) of the patch is stored in the memory 1-31 as the halftone dot area ratio of each color of the gray balance measurement patch of the halftone portion (step 127).

  Further, the CPU 1-1 stores in the memory 1-29 the position of the patch closest to the color value of N4 from the color value of each patch 5a of the color chart 5-1 obtained in step 122 (step 128). Further, the halftone dot area ratio of each color (cyan, magenta, yellow) of the patch is stored in the memory 1-32 as the halftone dot area ratio of each color of the gray balance measurement patch of the shadow portion (step 129).

  Then, the CPU 1-1 reads the halftone dot area ratios of the highlight portion, halftone portion, and shadow portion stored in the memories 1-30, 1-31, 1-32 (step 130), and the printing plate printing apparatus. 4 (step 131). For example, cyan “20%”, magenta “16%”, yellow “18%” as the halftone dot area ratio of each color in the highlight portion, and cyan “48%” as the halftone dot area ratio of each color in the halftone portion. As the halftone dot area ratio of each color of the magenta “38%”, yellow “41%”, and shadow portion, the highlight portion, halftone, cyan “76%”, magenta “67%”, yellow “71%”, etc. The halftone dot area ratio of each color of the color and shadow areas is output to the printing plate printing apparatus 4.

[Create plate]
The printing plate printing apparatus 4 creates printing plates of each color (sumi, cyan, magenta, yellow) for a printed matter including a pattern. At the time of creating this printing plate, for the cyan, magenta, and yellow printing plates, patches for gray balance measurement of the highlight portion, halftone portion, and shadow portion are formed on the color bar. When forming the gray balance measurement patch, the halftone dot area ratio of each color of the gray balance measurement patch in the highlight part, the halftone part, and the shadow part is set as the halftone dot area ratio determined by the main controller 1. Further, the gray balance measurement patches for the highlight portion, the halftone portion, and the shadow portion are provided only at one place for the whole, not for each region corresponding to the key zone of the ink fountain key. In the present embodiment, the color bar is provided almost in the center (hereinafter, this color bar is referred to as a color bar for density measurement & gray balance measurement).

  FIG. 8 is a diagram showing a printed matter printed by setting the printing plates of the respective colors (sumi, cyan, magenta, and yellow) created as described above in a management-target printing machine. On this printed matter 6, a strip-shaped color bar 6-2 for density measurement & gray balance measurement is printed in a blank portion avoiding the pattern portion 6-1. The color bar 6-2 for density measurement & gray balance measurement is composed of areas S1 to Sn including solid patches 6b1, 6b2, 6b3, 6b4 of sumi, cyan, magenta, and yellow. , Gray balance measurement patches PH, PM, and PS of the halftone portion and the shadow portion are printed.

[Density adjustment before quality judgment (Fig. 13)]
The printed material 6 is printed by a printing machine. A color bar 6-2 for density measurement & gray balance measurement is printed on the printed material 6. The color bar 6-2 includes areas S1 to Sn including solid patches 6b (6b1, 6b2, 6b3, 6b4) of the respective colors. Further, gray balance measurement patches PH, PM, and PS for the highlight portion, the halftone portion, and the shadow portion are printed at the center portion of the color bar 6-2.

  First, the operator sets the printed matter 6 immediately after printing by the printing machine as a measurement target on the measurement table 2-18 (FIG. 4) provided with the colorimeter 2-4. In this set state, the color bar 6-2 for density measurement & gray balance measurement printed on the printed material 6 is located on the lower surface of the head portion 2-4a of the colorimeter 2-4.

  Next, the operator inputs the reference density value and the allowable density value for the solid patch 6b of each color of the color bar 6-2 from the input device 1-4 (step 401). Also, the position of the solid patch 6b of each color in the color bar 6-2 is input from the input device 1-4 (step 402). In addition, the positions of the gray balance measurement patches PH, PM, and PS of the highlight portion, halftone portion, and shadow portion in the color bar 6-2 are input from the input device 1-4 (step 403).

  The CPU 1-1 stores the reference density value and the allowable density value for the solid patch 6b of each color of the input color bar 6-2 in the memories 1-10 and 1-11, and each color in the input color bar 6-2 is stored. The position of the solid patch 6b is stored in the memory 1-12, and the positions of the gray balance measurement patches PH, PM, PS in the highlight portion, halftone portion, and shadow portion in the input color bar 6-2 are stored in the memory 1-13. To remember. The CPU 1-1 calculates the position of each patch (solid patch 6b of each color, gray balance measurement patch PH, PM, PS) of the color bar 6-2 to be measured by the colorimeter 2-4. The measurement position is stored in the memory 1-26 (step 404).

  Next, the operator turns on the color bar measurement start switch of the input device 1-4. When the start switch is turned on (YES in step 405), the CPU 1-1 transfers the position (measurement position) of each patch to be measured stored in the memory 1-26 to the colorimeter control device 2 (step). 406). As a result, the colorimeter control device 2 measures the color data of each patch of the color bar 6-2 (solid patch 6b for each color, gray balance measurement patch PH, PM, PS) according to the flowchart shown in FIG. The

  The CPU 1-1 of the main control device 1 stores the color data of each patch (solid patch 6b, gray balance measurement patches PH, PM, PS) sent from the colorimeter control device 2 in the memory 1. -27 (steps 407 and 408). The CPU 1-1 calculates the density value of each color patch 6b of the areas S1 to Sn from the colorimetric data of the solid patch 6b of each color of the areas S1 to Sn from the colorimeter control device 2, and stores it in the memory 1-14. (Step 409).

  Then, the CPU 1-1 reads the reference density value of the solid patch of each color from the memory 1-10 (step 410), and the measured density value of the solid patch 6b of each color stored in the memory 1-14 and the reference density of the solid patch of each color. The difference from the value is calculated and stored in the memory 1-15 (step 411). Also, the absolute value of the difference between the measured density value of each color solid patch 6b stored in the memory 1-14 and the reference density value of each color solid patch is calculated and stored in the memory 1-16 (step 412).

  Next, the CPU 1-1 reads the permissible density value of the solid patch of each color from the memory 1-11 (step 413), and calculates the difference between the measured density value of the solid patch 6b of each color calculated in step 412 and the reference density value of each color. The absolute value is compared with the allowable density value of the solid patch of each color (step 414).

  The processing in steps 410 to 414 is performed for the solid patches 6b of the respective colors in the areas S1 to Sn of the color bar 6-2, and the absolute value of the difference between the measured density value and the reference density value in any one of the areas S1 to Sn. If there is a solid patch 6b exceeding the allowable density value (NO in step 414), the difference between the measured density value of the solid patch 6b of each color exceeding the allowable density value and the reference density value is transferred to the ink supply amount control device 3 ( In step 415), the opening amount (ink supply amount) of the key points in the printing unit of the color corresponding to the solid patch 6b is controlled so that the absolute value of the difference becomes equal to or less than the allowable density value. Then, the printed material 6 is printed again by the printing machine in which the ink supply amount is controlled, the printed material 6 immediately after printing is set on the measurement table 2-18 as a measurement object, and the operator turns on the color bar measurement start switch. (YES at step 405), the processing after step 406 is repeated.

[Quality judgment: QC bird's-eye view display processing (FIG. 14)]
In step 414, if the absolute value of the difference between the measured density value of each color solid patch 6b and the reference density value is equal to or less than the allowable density value for all the areas S1 to Sn of the color bar 6-2, the QC shown in FIG. The process proceeds to a bird's eye view display process.

  The CPU 1-1 of the main control device 1 reads the positions of the gray balance measurement patches PH, PM, PS in the highlight portion, halftone portion, and shadow portion of the color bar 6-2 stored in the memory 1-13. (Step 416 shown in FIG. 14), the color measurement data corresponding to the position of the read gray balance measurement patches PH, PM, PS is read from the memory 1-27, and the gray balance measurement data is read from the read color measurement data. The color values (L value, a value, b value) of the patches PH, PM, and PS are calculated and stored in the memory 1-17 (step 417).

  Further, the CPU 1-1 reads out the color values (L value, a value, b value) of N8, N6, and N4 of the Munsell color system gray color chart stored in the memory 1-25 (step 418). Then, the difference (Δa, Δb) between the chromaticness index (a value, b value) of the color value of the gray balance measurement patch PH in the highlight portion and the N8 chromaticness index (a value, b value) of the gray color chart. ), And Δa and Δb are stored in the memory 1-18 as a difference of the chromaticness index of the highlight portion (step 419). Further, a difference (ΔL) between the lightness index (L value) of the color value of the gray balance measurement patch PH in the highlight portion and the N8 lightness index (L value) of the gray color chart is obtained, and this ΔL is determined as the highlight portion. Is stored in the memory 1-18 as a difference in brightness index (step 420).

  Similarly, the difference (Δa) between the chromaticness index (a value, b value) of the color value of the gray balance measurement patch PM of the halftone portion and the N6 chromaticness index (a value, b value) of the gray color chart , Δb), and the Δa, Δb are stored in the memory 1-19 as the difference of the chromaticness index of the halftone part (step 421). Further, the difference (ΔL) between the lightness index (L value) of the color value of the gray balance measurement patch PM of the halftone portion and the N6 lightness index (L value) of the gray color chart is obtained, and this ΔL is determined as the halftone portion. Is stored in the memory 1-19 as a difference in brightness index (step 422).

  Similarly, the difference (Δa, b) between the chromaticness index (a value, b value) of the color value of the gray balance measurement patch PS in the shadow portion and the N4 chromaticness index (a value, b value) of the gray color chart. Δb) is obtained, and Δa and Δb are stored in the memory 1-20 as the difference of the chromaticness index of the shadow portion (step 423). Also, the difference (ΔL) between the lightness index (L value) of the color value of the gray balance measurement patch PS in the shadow part and the N4 lightness index (L value) of the gray color chart is obtained, and this ΔL is used as the lightness of the shadow part. The difference between the exponents is stored in the memory 1-20 (step 424).

Next, the CPU 1-1 determines ΔE = [(ΔL) ² + (Δa) ² + in accordance with the provisions of JISZ8730 based on the difference Δa, Δb in the chromaticness index in the highlight part and the difference ΔL in the brightness index in the highlight part. (Δb) ² )] The color difference of the highlight portion is obtained as ^½ and stored in the memory 1-21 (step 425).

Similarly, ΔE = [(ΔL) ² + (Δa) ² + (Δb) ² )] ^1/2 from the difference Δa, Δb of the chromaticness index of the halftone part and the difference ΔL of the lightness index of the halftone part. Then, the color difference of the halftone portion is obtained and stored in the memory 1-22 (step 426).

Similarly, from the difference Δa, Δb between the chromaticness index in the shadow part and the difference ΔL between the lightness index in the shadow part, ΔE = [(ΔL) ² + (Δa) ² + (Δb) ² )] ^1/2 The color difference of each part is obtained and stored in the memory 1-23 (step 427).

  Then, the CPU 1-1 displays the color difference ΔE of the highlight part, halftone part, and shadow part obtained in Steps 425, 426, and 427 as a line graph in the area 7-1 of the bird's eye view 7 shown in FIG. 15 (Step 428). ). In this line graph, “●” indicates ΔE in the highlight portion, “×” indicates ΔE in the halftone portion, and “Δ” indicates ΔE in the shadow portion.

  Further, the CPU 1-1 determines the difference Δa, Δb of the highlight portion, halftone portion, and shadow portion obtained in Steps 419, 421, 423 in the area 7-2 of the bird's eye view 7 in two-dimensional color coordinates. It is displayed (step 429). In the two-dimensional color coordinates, “●” indicates the coordinate positions of Δa and Δb of the highlight portion, “×” indicates the coordinate positions of Δa and Δb of the halftone portion, and “Δ” indicates Δa of the shadow portion. , Δb coordinate positions are shown. In addition, a hue ring 7a (see FIG. 16) is provided outside the two-dimensional color coordinates as a display unit representing the hue, so that the coordinate positions of Δa and Δb are easily understood intuitively. The hue ring is described in JISZ8721 as a hue display method.

  Further, the CPU 1-1 displays the difference ΔL in the brightness index of the highlight part, the halftone part, and the shadow part obtained in Steps 420, 422, and 424 as a line graph in the area 7-3 of the bird's eye view 7 (Step 430). . In this line graph, “●” indicates ΔL of the highlight portion, “×” indicates ΔL of the halftone portion, and “Δ” indicates ΔL of the shadow portion. In addition, a gray light and dark band 7b is provided beside the line graph as a display unit representing lightness, so that the value of ΔL can be intuitively easily understood.

  This bird's-eye view 7 is displayed on the screen of the display 1-5 or is launched from the output device 1-5. The operator looks at this bird's eye view 7 so that the color difference ΔE of the highlight portion, halftone portion, and shadow portion approaches the target color difference, and the chromaticness index of the highlight portion, halftone portion, and shadow portion. Difference Δa, Δb is made closer to the difference between the target chromaticness indices, and difference ΔL between the highlight part, halftone part, and shadow part is made closer to the difference between the target brightness indices. As described above, the ink supply amounts of the three basic colors are adjusted.

  Basically, the ink supply amount of the three basic colors is adjusted. If the adjustment of the ink supply amount of the three basic colors is not successful, a printing machine such as a printing pressure when printing is performed. And the conditions of the image printing apparatus (such as output calibration for adjusting the output of the image printing apparatus) when printing the pattern on the printing plate.

In this way, by adjusting the ink supply amounts of the three basic colors, it is possible to adjust not only the halftone portion but also the highlight portion and the shadow portion.
Further, by showing the customer a bird's eye view 7 of the printed matter after the color tone of the highlight portion, the halftone portion, and the shadow portion is matched, that is, the difference Δa, Δb in the chromaticness index of the highlight portion, the halftone portion, and the shadow portion. By disclosing the graphs of the lightness index difference ΔL and the color difference ΔE to the customer, it becomes possible to obtain the prior approval of the printed matter from the customer without showing the proof to the customer. In addition, it is possible to reproduce the color tone approved in advance by the customer without showing the proof or print sample to the printing operator.

In the above-described embodiment, “L ^* , a ^* , b ^* ” represented by the L ^* a ^* b ^* color system is used as the color value, but the L ^* u ^* v ^* color system is used. “L ^* , u ^* , v ^* ” represented may be used.
In the above-described embodiment, the gray balance measurement patches PH, PM, and PS are printed on the color bar 6-2 as the gray balance measurement unit. However, the gray balance measurement patches PH, PM, and PS are not necessarily printed on the color bar 6-2. Alternatively, it may be printed alone in the margin of the printed product 6.

Further, in the above-described embodiment, the chromaticness index differences Δa and Δb, the brightness index difference ΔL, and the color difference ΔE of the highlight portion, the halftone portion, and the shadow portion are automatically plotted in the QC bird's eye view 7. However, the operator may plot the QC bird's eye view 7.
In the above-described embodiment, the gray balance measurement units are the three gray balance measurement patches PH, PM, and PS of the highlight unit, the halftone unit, and the shadow unit. However, the number may be increased.

It is a block diagram of the quality control apparatus of printed matter which shows one embodiment of this invention. It is a block diagram which shows the internal structure of the colorimeter control apparatus used for this quality control apparatus. It is a block diagram which shows the internal structure of the ink supply amount control apparatus used for this quality control apparatus. It is a side view which shows the installation condition of a colorimeter. It is a figure which shows the patch for gray balance measurement of the highlight part printed as a gray balance measurement part, the patch for gray balance measurement of a halftone part, and the patch for gray balance measurement of a shadow part. It is a figure which shows the arrangement | sequence of the brightness and saturation in the equi-hue surface of the Munsell color system. It is a top view which shows the outline of the printed matter printed by the printing machine. It is a top view which shows the outline of the printed matter (printed matter with which the color bar for printed matter density measurement & gray balance measurement was printed) printed by the printing machine. It is a flowchart for demonstrating the density adjustment before the halftone dot area rate of the patch for gray balance measurement by a main control apparatus. It is a flowchart for demonstrating the processing operation in a colorimeter control apparatus. It is a flowchart for demonstrating the processing operation in an ink supply amount control apparatus. It is a flowchart for demonstrating the halftone dot area rate determination of the patch for gray balance measurement by the main control apparatus. It is a flowchart for demonstrating the density adjustment before the quality judgment by a main control apparatus. It is a flowchart for demonstrating the display of QC bird's-eye view by the main control apparatus. It is a figure which illustrates QC bird's-eye view displayed. It is a figure which shows the hue ring provided in the outer side of the two-dimensional color coordinate where the difference of the chromaticness index of this QC bird's-eye view is displayed.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Main control apparatus (main control apparatus), 2 ... Colorimeter control apparatus (colorimeter control apparatus), 3 ... Ink supply amount control apparatus, 4 ... Printing plate printing apparatus, 1-1 ... CPU, 1 -2 ... RAM, 1-3 ... ROM, 1-3 ... input device, 1-5 ... display, 1-6 ... output device, 1-7 to 1-9 ... input / output interfaces (I / O, I / F), 1-10 to 1-32 ... Memory, 2-1 ... CPU, 2-2 ... RAM, 2-3 ... ROM, 2-4 ... Colorimeter, 2-5 ... Motor for moving the colorimeter, 2-6 ... Rotary encoder, 2-7 ... Motor driver, 2-8 ... Counter, 2-9 ... A / D converter, 2-10 to 2-12 ... Interface (I / O, I / F), 2 -13, 2-14 ... Memory, 3-1 ... CPU, 3-2 ... RAM, 3-3 ... ROM, 3-4 (3-41-3-4n) ... Ink Bokey opening adjustment device, 3-5 (3-51 to 3-5n), 3-6 ... interface (I / O, I / F), 3-71 to 1-36 ... memory, PH ... highlight section Gray balance measurement patch, PM: Gray balance measurement patch for halftone part, PS ... Gray balance measurement patch for shadow part, 5 ... Printed matter (print for making gray balance measurement patch), 5-1 ... Color chart 5-2 ... Color bar, 5a ... Patch, 5b1, 5b2, 5b3, 5b4 ... Solid patch, S1-Sn ... Area, 6 ... Printed matter, 6-1 ... Picture part, 6-2 ... Color bar (Density measurement & Gray (Color bars for balance measurement), 6b1, 6b2, 6b3, 6b4 ... solid patch, 7 ... QC bird's-eye view, 7-1 ... display area of ΔE, 7-2 ... display area of Δa, Δb, 7-3 ... display of ΔL region , 7a ... hue circle, 7b ... gray light and dark belt.

Claims (24)

Highlight portion with small dot area ratio of cyan, magenta and yellow, shadow portion with large dot area ratio of cyan, magenta and yellow, and dot area ratio of cyan, magenta and yellow are larger than the highlight area. And printing a halftone part smaller than the shadow part on a printed matter as a gray balance measuring part,
Measuring the color values of the highlight portion, halftone portion and shadow portion;
And determining the quality of the printed matter from the measured color values of the highlight portion, halftone portion and shadow portion. In the quality control method of the printed matter described in Claim 1,
Obtaining a difference in chromaticness index of the highlight portion in the color system from the measured color value of the highlight portion and the reference color value of the highlight portion;
Obtaining a difference in chromaticness index of the halftone part in the color system from the measured color value of the halftone part and the reference color value of the halftone part;
A quality control method for printed matter, comprising: obtaining a difference in chromaticness index of the shadow part in a color system from the measured color value of the shadow part and the reference color value of the shadow part. In the quality control method of the printed matter described in Claim 2,
Determining a difference in brightness index of the highlight portion in the color system from the measured color value of the highlight portion and the reference color value of the highlight portion;
Determining a difference in lightness index of the halftone part in the color system from the measured color value of the halftone part and the reference color value of the halftone part;
A quality control method for printed matter, comprising: calculating a difference in lightness index of the shadow portion in a color system from the measured color value of the shadow portion and a reference color value of the shadow portion. In the quality control method of the printed matter described in Claim 3,
Obtaining a color difference of the highlight portion in the color system from the measured color value of the highlight portion and the reference color value of the highlight portion;
Obtaining the color difference of the halftone part in the color system from the measured color value of the halftone part and the reference color value of the halftone part;
A quality control method for printed matter, comprising: obtaining a color difference of the shadow part in a color system from the measured color value of the shadow part and a reference color value of the shadow part. In the quality control method of the printed matter described in any one of Claims 2-4,
The reference color value of the highlight portion is one color value of a relatively large brightness index among gray color charts of the Munsell color system,
The reference color value of the shadow portion is one color value of a Munsell color system gray color chart having a relatively small brightness index,
The reference color value of the halftone part is smaller than the lightness index of the reference color value of the highlight part of the Munsell color system gray color chart and larger than the lightness index of the reference color value of the shadow part. A quality control method for printed matter, characterized by having one color value. In the quality control method of the printed matter described in any one of Claims 2-4,
The reference color value of the highlight portion is the color value of N8 in the gray color chart of the Munsell color system,
The reference color value of the shadow portion is the color value of N4 of the Munsell color system gray color chart,
A quality control method for printed matter, wherein a reference color value of the halftone portion is a color value of N6 of a Munsell color system gray color chart. In the quality control method of the printed matter described in Claim 1,
The highlight, cyan, magenta, and yellow meshes so that the color value of the highlight portion becomes a color value near one of the gray color charts of the Munsell color system having a relatively large brightness index. Point area ratio is determined,
The shaded area of cyan, magenta, and yellow in the shadow part so that the color value in the shadow part becomes a color value in the vicinity of one color value of the Munsell color system with a relatively small brightness index. Rate is determined,
One color in which the color value of the halftone portion is smaller than the lightness index of the reference color value of the highlight portion and greater than the lightness index of the reference color value of the shadow portion of the Munsell color system gray color chart A quality control method for printed matter, characterized in that the halftone dot area ratios of cyan, magenta, and yellow of the halftone part are determined so that the color value is close to the value. In the quality control method of the printed matter described in Claim 1,
The dot area ratios of cyan, magenta, and yellow of the highlight portion are determined so that the color value of the highlight portion becomes a color value near the N8 color value of the Munsell color system gray color chart,
The halftone dot area ratio of cyan, magenta, and yellow of the shadow portion is determined so that the color value of the shadow portion is a color value near the N4 color value of the Munsell color system gray color chart, The halftone dot area ratios of cyan, magenta, and yellow of the halftone part are determined so that the color value of the halftone portion becomes a color value in the vicinity of the N6 color value of the Munsell color system gray color chart Quality control method for printed materials. In the quality control method of the printed matter described in Claim 4,
Displaying the obtained color difference of the highlight part, the color difference of the halftone part and the color difference of the shadow part in a line graph;
Displaying the obtained difference in the chromaticness index of the highlight portion, the difference in the chromaticness index of the halftone portion, and the difference in the chromaticness index of the shadow portion on a two-dimensional color coordinate;
Displaying the difference in the brightness index of the highlighted portion, the difference in the brightness index of the halftone portion, and the difference in the brightness index of the shadow portion as a line graph. Management method. Highlight portion with small dot area ratio of cyan, magenta and yellow, shadow portion with large dot area ratio of cyan, magenta and yellow, and dot area ratio of cyan, magenta and yellow are larger than the highlight area. And printing a halftone part smaller than the shadow part on a printed matter as a gray balance measuring part,
Measuring the color values of the highlight portion, halftone portion and shadow portion;
A step of obtaining a difference in chromaticness index, a difference in lightness index and a color difference of the highlight portion in a color system from the measured color value of the highlight portion and a reference color value of the highlight portion;
Obtaining a difference in chromaticness index, brightness index and color difference of the halftone part in the color system from the measured color value of the halftone part and the reference color value of the halftone part;
A step of obtaining a difference in chromaticness index, brightness index and color difference of the shadow part in a color system from the measured color value of the shadow part and the reference color value of the shadow part;
Displaying the obtained color difference of the highlight part, the color difference of the halftone part and the color difference of the shadow part in a line graph;
Displaying the obtained difference in the chromaticness index of the highlight portion, the difference in the chromaticness index of the halftone portion, and the difference in the chromaticness index of the shadow portion on a two-dimensional color coordinate;
Displaying the difference in the brightness index of the highlighted portion, the difference in the brightness index of the halftone portion, and the difference in the brightness index of the shadow portion as a line graph. Management method. In the quality control method of the printed matter described in Claim 9 or 10,
A display unit representing a hue is provided outside a two-dimensional color coordinate for displaying a difference in chromaticness index in the highlight portion, a difference in chromaticness index in the halftone portion, and a difference in chromaticness index in the shadow portion. A quality control method for printed matter. In the quality control method of the printed matter described in Claim 9 or 10,
A printed matter, characterized in that a display unit representing brightness is provided beside a line graph displaying the difference in brightness index of the highlight part, the difference in brightness index of the halftone part, and the difference in brightness index of the shadow part. Quality control method. Highlight portion with small dot area ratio of cyan, magenta and yellow, shadow portion with large dot area ratio of cyan, magenta and yellow, and dot area ratio of cyan, magenta and yellow are larger than the highlight area. And means for printing a halftone part smaller than the shadow part on a printed matter as a gray balance measuring part,
A quality control apparatus for printed matter, comprising: means for measuring color values of the highlight portion, halftone portion, and shadow portion. In the quality control apparatus of the printed matter described in Claim 13,
Means for determining a difference in chromaticness index of the highlight portion in the color system from the measured color value of the highlight portion and the reference color value of the highlight portion;
Means for determining a difference in chromaticness index of the halftone part in the color system from the measured color value of the halftone part and the reference color value of the halftone part;
A quality control apparatus for printed matter, comprising: means for obtaining a difference in chromaticness index of the shadow part in a color system from the measured color value of the shadow part and the reference color value of the shadow part. In the quality control apparatus of the printed matter described in Claim 14,
Means for determining a difference in brightness index of the highlight portion in the color system from the measured color value of the highlight portion and the reference color value of the highlight portion;
Means for determining a difference in lightness index of the halftone part in the color system from the measured color value of the halftone part and the reference color value of the halftone part;
A quality control apparatus for printed matter, comprising: means for obtaining a difference in lightness index of the shadow part in a color system from the measured color value of the shadow part and a reference color value of the shadow part. In the quality control apparatus of the printed matter described in Claim 15,
Means for determining the color difference of the highlight portion in the color system from the measured color value of the highlight portion and the reference color value of the highlight portion;
Means for obtaining a color difference of the halftone part in the color system from the measured color value of the halftone part and the reference color value of the halftone part;
A quality control apparatus for printed matter, comprising: means for obtaining a color difference of the shadow portion in a color system from the measured color value of the shadow portion and a reference color value of the shadow portion. In the quality control apparatus of the printed matter described in any one of Claims 14-16,
The reference color value of the highlight portion is one color value of a relatively large brightness index among gray color charts of the Munsell color system,
The reference color value of the shadow portion is one color value of a Munsell color system gray color chart having a relatively small brightness index,
The reference color value of the halftone part is smaller than the lightness index of the reference color value of the highlight part of the Munsell color system gray color chart and larger than the lightness index of the reference color value of the shadow part. A quality control device for printed matter characterized by having one color value. In the quality control apparatus of the printed matter described in any one of Claims 14-16,
The reference color value of the highlight portion is the color value of N8 in the gray color chart of the Munsell color system,
The reference color value of the shadow portion is the color value of N4 of the Munsell color system gray color chart,
A quality control device for printed matter, wherein a reference color value of the halftone portion is a color value of N6 of the Munsell color system gray color chart. In the quality control apparatus of the printed matter described in Claim 13,
The highlight, cyan, magenta, and yellow meshes so that the color value of the highlight portion becomes a color value near one of the gray color charts of the Munsell color system having a relatively large brightness index. Point area ratio is determined,
The shaded area of cyan, magenta, and yellow in the shadow part so that the color value in the shadow part becomes a color value in the vicinity of one color value of the Munsell color system with a relatively small brightness index. Rate is determined,
One color in which the color value of the halftone portion is smaller than the lightness index of the reference color value of the highlight portion and greater than the lightness index of the reference color value of the shadow portion of the Munsell color system gray color chart A quality control apparatus for printed matter, wherein the halftone dot area ratios of cyan, magenta, and yellow of the halftone part are determined so that the color values are close to the value. In the quality control apparatus of the printed matter described in Claim 13,
The dot area ratios of cyan, magenta, and yellow of the highlight portion are determined so that the color value of the highlight portion becomes a color value near the N8 color value of the Munsell color system gray color chart,
The halftone dot area ratios of cyan, magenta and yellow of the shadow part are determined so that the color value of the shadow part becomes a color value near the N4 color value of the Munsell color system gray color chart, and the halftone part The halftone dot area ratios of cyan, magenta, and yellow of the halftone part are determined so that the color value of the halftone portion becomes a color value in the vicinity of the N6 color value of the Munsell color system gray color chart Print quality control device. In the quality control apparatus of the printed matter described in Claim 16,
Means for displaying the obtained color difference of the highlight portion, the color difference of the halftone portion, and the color difference of the shadow portion in a line graph;
Means for displaying on a two-dimensional color coordinate the difference in the chromaticness index of the highlighted portion, the difference in the chromaticness index of the halftone portion, and the difference in the chromaticness index of the shadow portion;
And a means for displaying the difference in the lightness index of the highlighted portion, the difference in the lightness index in the halftone portion, and the difference in the lightness index in the shadow portion in a line graph. Management device. Highlight portion with small dot area ratio of cyan, magenta and yellow, shadow portion with large dot area ratio of cyan, magenta and yellow, and dot area ratio of cyan, magenta and yellow are larger than the highlight area. And means for printing a halftone part smaller than the shadow part on a printed matter as a gray balance measuring part,
Means for measuring color values of the highlight portion, halftone portion and shadow portion;
Means for determining a difference in chromaticness index, a difference in lightness index and a color difference in the highlight portion in a color system from the measured color value of the highlight portion and the reference color value of the highlight portion;
Means for determining a difference in chromaticness index, a difference in lightness index and a color difference of the halftone part in a color system from the measured color value of the halftone part and the reference color value of the halftone part;
Means for determining a difference in chromaticness index, a difference in brightness index and a color difference of the shadow part in the color system from the measured color value of the shadow part and the reference color value of the shadow part;
Means for displaying the obtained color difference of the highlight portion, the color difference of the halftone portion, and the color difference of the shadow portion in a line graph;
Means for displaying on a two-dimensional color coordinate the difference in the chromaticness index of the highlighted portion, the difference in the chromaticness index of the halftone portion, and the difference in the chromaticness index of the shadow portion;
And a means for displaying the difference in the lightness index of the highlighted portion, the difference in the lightness index in the halftone portion, and the difference in the lightness index in the shadow portion in a line graph. Management device. In the quality control apparatus of the printed matter described in Claim 21 or 22,
A display unit representing a hue is provided outside a two-dimensional color coordinate for displaying a difference in chromaticness index in the highlight portion, a difference in chromaticness index in the halftone portion, and a difference in chromaticness index in the shadow portion. A quality control device for printed matter. In the quality control apparatus of the printed matter described in Claim 21 or 22,
A printed matter, characterized in that a display unit representing brightness is provided beside a line graph displaying the difference in brightness index of the highlight part, the difference in brightness index of the halftone part, and the difference in brightness index of the shadow part. Quality control equipment.

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