JP4003760B2 - Image printing to improve image quality - Google Patents

Description

  The present invention relates to a printing technique for printing an image by discharging a plurality of inks onto a printing medium.

  In recent years, inkjet printers have been widely used as image printing apparatuses. Various types of print media are used according to user preferences. For example, so-called glossy paper having relatively high gloss, so-called plain paper, matte paper, etc. having relatively low gloss are often used as print media.

  The amount of ink ejected to the print medium is determined by the image data to be printed. In a low lightness area, the amount of ink ejected increases, and in a high lightness area, the amount of ink ejected decreases.

  When printing on a relatively strong glossy print medium, the gloss tends to increase as the amount of ejected ink increases. For example, when an image with a person on a white background is printed, the area of a person with a large amount of ink ejection has a high gloss, and the background area with a small amount of ink ejection has a low gloss. For this reason, there is a problem that a person who sees an image feels a sense of incongruity that gloss is different depending on a region even in the same image.

  When printing on a print medium having relatively low gloss, the ejected ink is easily absorbed by the print medium. For this reason, the ink color material remaining on the surface of the print medium is reduced, and the portion of the print medium that is originally desired to be hidden in the ink appears on the surface, and it is difficult to obtain the required color of the ink. This phenomenon (color unevenness) is very conspicuous particularly in a region where the amount of ink discharged is large, for example, a region where ink is discharged to almost all pixels. For example, when an image with a person on a white background is printed, there is a problem that this phenomenon occurs in an area of a person with a large ink ejection amount, and the image becomes rough.

  As described above, there is a problem in that sufficient image quality may not be obtained in normal ink printing.

  The present invention has been made to solve the above-described problems in the prior art, and an object thereof is to provide a printing technique that stably improves image quality.

  In order to solve at least a part of the above problems, a first printing apparatus according to the present invention is a printing apparatus that prints an image by ejecting ink onto a printing medium, and includes at least one kind including a coloring material. In at least a part of the total range that can be taken by the discharge amount of the colored ink, a print head capable of discharging the colored ink, and an improved ink for improving the image quality of the printed image, An adjustment unit that adjusts the discharge amount of the improvement ink based on the discharge amount of the colored ink so that the discharge amount of the improvement ink becomes a variable value that is not zero.

  Since the first printing apparatus adjusts the ejection amount of the improved ink for improving the image quality of the image based on the ejection amount of the colored ink, the improved ink is ejected without excess or deficiency to improve the image quality. There is an advantage that you can.

  In the first printing apparatus, a first print medium having a relatively high gloss and a second print medium having a relatively low gloss can be used, and the adjustment unit uses the first print medium. In this case, the first discharge amount of the improved ink in the region where the colored ink is discharged to almost all the pixels is smaller than the second discharge amount of the improved ink in the region where the colored ink is not discharged. It is preferable to have the first adjustment mode for improving the uneven glossiness of the printed image by setting so as to be.

  By doing so, the gloss in the region where the ejection amount of ink other than the improved ink is small can be enhanced by the improved ink. Therefore, there is an advantage that the difference in gloss between the area where the ejection amount of ink other than the improved ink is large and the area where the ink is small can be reduced, and uneven gloss can be improved.

  In the first printing apparatus, it is possible to use a first print medium having a relatively high gloss and a second print medium having a relatively low gloss, and the adjustment unit uses the second print medium. In such a case, the first discharge amount of the improved ink in a region where the colored ink is discharged to almost all pixels is larger than the second discharge amount of the improved ink in a region where the colored ink is not discharged. It is preferable to have a second adjustment mode for improving unevenness in color development of a printed image by setting so as to be.

  By doing so, there is an advantage that unevenness in coloring of the discharged ink can be improved by the improved ink.

  In the first printing apparatus, the adjustment unit is represented by a second color system composed of ink usable in the printing unit from the first image data represented by the first color system. It is preferable to include an ink amount data conversion unit that performs conversion into the second image data that has been performed using a lookup table.

  By doing so, there is an advantage that the process of converting the image data into the ink amount data can be quickly performed by referring to the lookup table.

  In the first printing apparatus, the adjustment unit includes a plurality of lookup tables prepared in advance corresponding to a plurality of adjustment modes of the adjustment unit, and the ink amount data conversion unit includes the adjustment unit. It is preferable to use a lookup table corresponding to the adjustment mode to be used.

  By doing so, there is an advantage that printing that realizes an improvement in desired image quality can be performed.

  In the first printing apparatus, it is preferable that the improvement ink is a transparent liquid not containing a coloring material.

  By doing so, there is an advantage that the image quality can be improved using the improved ink without modifying the image reproduced with the colored ink.

  A second printing apparatus of the present invention is a printing apparatus that prints an image by ejecting ink onto a printing medium, and improves at least one kind of colored ink including a coloring material and the image quality of the printed image. A print head capable of ejecting the improved ink, and an adjustment unit that adjusts the ejection amount of the improved ink based on the ejection amount of the colored ink. The first print medium having a high gloss and the second print medium having a relatively low gloss can be used, and the adjustment unit can use colored ink for almost all pixels when the first print medium is used. Is set so that the first discharge amount of the improved ink in the region where the ink is discharged is smaller than the second discharge amount of the improved ink in the region where the colored ink is not substantially discharged. Glossy When the second print medium is used in the first adjustment mode for improving color, the first discharge amount of the improvement ink in the area where the color ink is discharged to almost all pixels is And a second adjustment mode for improving unevenness in coloring of the printed image by setting the second ink to be larger than the second discharge amount of the improved ink in a region where there is almost no discharge.

  This second printing apparatus has an advantage that it is possible to improve gloss unevenness and color unevenness of a printed image using an improvement ink that improves the image quality of the image.

  A third printing apparatus of the present invention is a printing apparatus that prints an image by ejecting ink onto a print target area of a print medium, and includes at least one type of colored ink including a coloring material, and the image quality of the printed image. A print head capable of ejecting an improved ink for improving the ink, and an ink ejection amount determination unit that determines an ejection amount of each ink ejected from the print head. The portion of the improved ink is formed so that the ink dots of the improved ink are substantially uniformly dispersed in an area within the print target area where the colored ink is discharged at least in a predetermined discharge amount range that is not zero. Determine the discharge rate.

  Since the ink dots of the improved ink are formed almost uniformly in the area on the print medium where the discharge amount of the colored ink is within a predetermined range, the image quality can be improved uniformly with the improved ink for that area. Further, since the ink dots of the improved ink are arranged in a dispersed manner, it is possible to suppress the possibility that the image quality is deteriorated due to excessive ejection of the improved ink.

  The ink discharge amount determination unit determines that the improvement ink discharge amount is zero in the first region where the color ink discharge amount is zero, and the color ink discharge amount is not zero in the second region. The ejection amount of the improved ink may be determined so that the ink dots of the improved ink are formed in a substantially uniform manner.

  An image area where the discharge amount of colored ink is zero may not require image quality improvement. In the above configuration, unnecessary ink is not ejected in such a region, so that the ink can be saved.

  Alternatively, the ink discharge amount determination unit sets the discharge amount of the improvement ink so that the ink dots of the improvement ink are substantially uniformly dispersed in the print target region regardless of the discharge amount of the colored ink. It may be determined.

  According to this configuration, since the dots of the improved ink are uniformly distributed in the print target area regardless of the discharge amount of the color ink, the boundary between the area where the color ink is discharged and the area where the color ink is not discharged becomes conspicuous. Can be prevented.

  The ink dots of the improved ink are preferably formed substantially uniformly at a predetermined dot recording rate within a range of about 1% to about 20%.

  If the ink discharge amount is within this range, it is possible to prevent the colored ink from spreading due to the excessive improvement ink discharge, the time required for the discharged ink to dry, or the printing medium from undulating. it can. Further, it is possible to achieve a certain level of image quality improvement effect.

  The present invention can be realized in various forms, for example, a printing method and a printing apparatus, a printing control method and a printing control apparatus, a computer program for realizing the functions of these methods or apparatuses, The present invention can be realized in the form of a recording medium that records a computer program, a data signal that includes the computer program and is embodied in a carrier wave, and the like.

Next, embodiments of the present invention will be described in the following order based on examples.
A. Device configuration:
B. Example of first adjustment mode:
C. Example of second adjustment mode:
D. Variation:

A. Device configuration:
FIG. 1 is a block diagram showing the configuration of a printing system as an embodiment of the present invention. This printing system includes a computer 90 as a print control device and a printer 20 as a printing unit. The printer 20 and the computer 90 can be referred to as a “printing apparatus” in a broad sense.

  In the computer 90, an application program 95 operates under a predetermined operating system. The operating system incorporates a video driver 91 and a printer driver 96 that functions as an adjustment unit or an ink discharge amount determination unit of the present invention, and transfers from the application program 95 to the printer 20 via these drivers. Print data PD for output is output. The application program 95 that performs image retouching or the like performs desired processing on the image to be processed, and displays an image on the CRT 21 via the video driver 91.

  When the application program 95 issues a print command, the printer driver 96 of the computer 90 receives the image data from the application program 95 and converts it into print data PD to be supplied to the printer 20. In the example shown in FIG. 1, the printer driver 96 includes a resolution conversion unit 97, an ink amount data conversion unit 98, a halftone processing unit 99, a print data generation unit 100, a lookup table 102, And an adjustment mode selection unit 103.

  The resolution converter 97 plays a role of converting the resolution of the color image data formed by the application program 95 (that is, the number of pixels per unit length) into the print resolution. The image data thus converted in resolution is still image information composed of three color components of RGB. The ink amount data conversion unit 98 refers to the look-up table 102 and converts the RGB image data (first image data) of each pixel into multi-gradation data corresponding to a plurality of ink amounts that can be used by the printer 20. (Second image data).

  When there are a plurality of adjustment modes that can be used, the user can select an adjustment mode to be used by using the adjustment mode selection unit 103. When there is only one adjustment mode that can be used, the process by the adjustment mode selection unit 103 or the adjustment mode selection unit 103 itself can be omitted.

  The lookup table 102 is prepared corresponding to the adjustment modes that can be selected by the adjustment mode selection unit 103. The ink amount data conversion unit 98 selects and refers to a lookup table corresponding to the selected adjustment mode. The types of adjustment modes, the ink amount data conversion unit 98, and the lookup table 102 will be described later.

  The ink amount data has, for example, 256 gradation values. The halftone processing unit 99 performs so-called halftone processing to generate halftone image data from the ink amount data. The halftone image data is rearranged in the order of data to be transferred to the printer 20 by the print data generation unit 100, and is output as final print data PD. The print data PD includes raster data indicating the dot recording state during each main scan and data indicating the sub-scan feed amount.

  The printer driver 96 corresponds to a program for realizing a function for generating the print data PD. A program for realizing the function of the printer driver 96 is supplied in a form recorded on a computer-readable recording medium. Such recording media include flexible disks, CD-ROMs, magneto-optical disks, IC cards, ROM cartridges, punch cards, printed matter on which codes such as bar codes are printed, computer internal storage devices (such as RAM and ROM). A variety of computer-readable media such as a memory) and an external storage device can be used.

  FIG. 2 is a schematic configuration diagram of the printer 20. The printer 20 includes a sub-scan feed mechanism that transports the printing paper P in the sub-scan direction by the paper feed motor 22, and a main scan feed mechanism that reciprocates the carriage 30 in the axial direction (main scan direction) of the platen 26 by the carriage motor 24. A head drive mechanism that drives the print head unit 60 mounted on the carriage 30 to control ink ejection and dot formation, the paper feed motor 22, the carriage motor 24, the print head unit 60, and the operation panel 32. And a control circuit 40 that manages the exchange of the above signals. The control circuit 40 is connected to the computer 90 via the connector 56.

  The sub-scan feed mechanism for transporting the printing paper P includes a gear train (not shown) that transmits the rotation of the paper feed motor 22 to the platen 26 and a paper transport roller (not shown). Further, the main scanning feed mechanism for reciprocating the carriage 30 has an endless drive belt 36 between the carriage motor 24 and a slide shaft 34 that is installed in parallel with the axis of the platen 26 and slidably holds the carriage 30. And a position sensor 39 for detecting the origin position of the carriage 30.

  FIG. 3 is a block diagram showing the configuration of the printer 20 with the control circuit 40 as the center. The control circuit 40 is configured as an arithmetic and logic circuit including a CPU 41, a programmable ROM (PROM) 43, a RAM 44, and a character generator (CG) 45 that stores a dot matrix of characters. The control circuit 40 further includes an I / F dedicated circuit 50 dedicated to interface with an external motor and the like, and a head that is connected to the I / F dedicated circuit 50 and drives the print head unit 60 to eject ink. A drive circuit 52 and a motor drive circuit 54 for driving the paper feed motor 22 and the carriage motor 24 are provided. The I / F dedicated circuit 50 incorporates a parallel interface circuit and can receive print data PD supplied from the computer 90 via the connector 56. The circuit built in the I / F dedicated circuit 50 is not limited to the parallel interface circuit, but can be determined in consideration of the ease of connection with the computer 90 such as a universal serial bus interface circuit. The printer 20 executes printing according to the print data PD. The RAM 44 functions as a buffer memory for temporarily storing raster data.

  The print head unit 60 has a print head 28 and can be mounted with an ink cartridge of available ink. The print head unit 60 is attached to and detached from the printer 20 as one component. That is, when the print head 28 is to be replaced, the print head unit 60 is replaced. On the lower surface of the print head 28, nozzles for ejecting usable ink are provided.

  In the printer 20 having the hardware configuration described above, the carriage 30 is reciprocated by the carriage motor 24 while the printing paper P is transported by the paper feed motor 22 and simultaneously the piezo elements of the print head 28 are driven, so that each ink A droplet is ejected to form an ink dot, and a print image with improved image quality is formed on the print paper P.

  FIG. 4 is an explanatory diagram showing the arrangement of the nozzles Nz on the lower surface of the print head 28. On the lower surface of the print head 28, nozzle groups for ejecting black ink K, cyan ink C, light cyan ink LC, magenta ink M, light magenta ink LM, yellow ink Y, and improvement ink CL are formed. . The ink that can be used in addition to the improvement ink CL is not limited to the six inks K, C, LC, M, LM, and Y, and can be arbitrarily set according to the preference of the image quality of the print image. be able to. For example, four inks K, C, M, and Y may be used, or only the black ink K may be used. Further, a combination of dark yellow ink having a lightness lower than that of the yellow ink Y, gray ink having a lightness higher than that of the black ink K, a blue ink, a red ink, and a green ink may be used. .

  As the improvement ink CL, it is preferable to use a colorless and transparent ink that has the same gloss as other inks and improves the color developability of the other inks. As such an improved ink, for example, the ink described in JP-A-8-60059 can be used. By doing so, the image quality of the printed image can be improved without readjusting the ejection amount of other ink. Further, by using an ink that improves water resistance and light resistance, the water resistance and light resistance of a printed image can be improved. In this case, it is possible to improve the water resistance and light resistance of the print medium by using the first adjustment mode in which more improved ink is discharged in a region where the discharge amount of the colored ink is small. Further, by using the second adjustment mode in which more improved ink is discharged in a region where the amount of colored ink discharged is large, the water resistance and light resistance of the region where ink is discharged can be improved.

  FIG. 5 is an explanatory diagram for explaining the outline of the two adjustment modes in the embodiment. In this example, a person is printed on a white background. 5A shows a first adjustment mode applied when printing on glossy paper GP, and FIG. 5B shows a second adjustment mode applied when printing on non-glossy paper NP. The adjustment mode is shown. These adjustment modes are automatically set by the printer driver 96 by setting the adjustment mode selection unit 103 to use plain paper or glossy paper from a user setting screen (not shown) of the printer driver 96. Selected.

  In the first adjustment mode shown in FIG. 5A, in the person region, inks K, C, LC, M, LM, and Y (hereinafter, colored inks) other than the improvement ink CL are used to reproduce the person color. Are called one or more types. Since the background region is a white background, colored ink is not ejected. The improvement ink CL is ejected in a background area where colored ink is not ejected, and is hardly ejected in a person area where colored ink is ejected. When the improvement ink is not used, since the ink is not ejected to the background area, the gloss of the background area becomes weaker than that of the person area. However, in the first adjustment mode, the improvement ink is ejected to the background area where the colored ink is not ejected, so that the gloss of the background area can be increased. As a result, the difference in gloss between the person area and the background area can be reduced, and uneven gloss can be improved. Furthermore, since the improvement ink is hardly ejected to the person area, the printing medium is prevented from undulating and the time required for the discharged ink to dry is prevented, and the use amount of the improvement ink is saved. be able to.

  The ejection amount of the improvement ink is preferably changed according to the ejection amount of the colored ink that varies depending on the image data. By so doing, uneven glossiness in the image can be improved more finely. Details will be described later.

  In the second adjustment mode shown in FIG. 5B, colored ink is ejected onto the person area in order to reproduce the person's color. Since the background region is a white background, colored ink is not ejected. The improvement ink CL is also ejected in the person area where the colored ink is ejected, and is hardly ejected in the background area where the colored ink is not ejected. When the improvement ink is not used, the color ink discharged to the person area is absorbed by the print medium, resulting in uneven coloring. However, in the second adjustment mode, since the improvement ink is ejected to the person area where the colored ink is ejected, the color unevenness in the person area can be improved. Furthermore, since almost no improved ink is ejected to the background area, the amount of improved ink used can be saved.

  The ejection amount of the improvement ink is preferably changed according to the ejection amount of the colored ink that varies depending on the image data. By so doing, uneven coloring in the image can be improved more finely. Details will be described later.

B. Example of first adjustment mode:
B1. Example 1 of the first adjustment mode 1:
FIG. 6 is a graph for explaining the relationship between the discharge amount of the colored ink and the discharge amount of the improvement ink. 6A shows the relationship between the discharge amount VS of colored ink and the discharge amount VCL of improved ink, and FIG. 6B shows the total value of the discharge amount VS of colored ink and the discharge amount of colored ink and improved ink. The relationship with VT (= VS + VCL) is shown. The horizontal axis is the discharge amount VS of colored ink, and the vertical axis is the discharge amount of ink indicated in the legend.

  As the ejection amount, a recording rate is used in which any ink is ejected to all pixels at 100%. When dots of different sizes can be formed in one pixel area, it is preferable to set the relationship between the ejection amounts using the volume of the ejected ink as the ejection amount. The discharge amount VS of colored ink is a total value of discharge amounts of ink that can be used as colored ink. Therefore, when a plurality of types of ink are ejected at the same pixel position, the colored ink ejection amount VS and the total ejection amount VT are larger than 100%. When the gloss differs for each ink, it is preferable to calculate the total value by applying a weight with a different coefficient for each ink.

  The improved ink ejection amount VCL is a value when the colored ink ejection amount VS is approximately 0% (second ejection amount), and a value when the colored ink ejection amount VS is approximately 100% (first ejection amount). ) Is set to be larger than. Therefore, the gloss of the area where the discharge amount VS of the colored ink is small can be enhanced by the improved ink, and the difference in gloss from the area where the discharge amount VS of the color ink is large can be reduced. Further, in a region where the discharge amount VS of colored ink is large, the discharge amount VCL of the improvement ink is reduced so as not to discharge unnecessary improvement ink. Therefore, it is possible to prevent the printing medium from undulating, to prevent the time required for the discharged ink to dry, or to save the amount of improved ink used. Further, in the first embodiment, the value of the improved ink discharge amount VCL is set so that the value of the total discharge amount VT is not less than the first predetermined value A that is not 0 regardless of the color ink discharge amount VS. . That is, the ejection amount of the improved ink is set so that the total amount of all ejected inks is equal to or greater than the first predetermined value A in the entire area of the print image. As a result, gloss over a predetermined intensity can be maintained in the entire area of the printed image, and the low gloss area can be prevented from being noticeable. In the example of FIG. 6, the first predetermined value A is 30%, but this value A can be determined according to the type of ink used and the type of print medium.

  Next, the ink amount data conversion unit 98 (FIG. 1) in this embodiment will be described. The ink amount data conversion unit 98 selects and refers to the look-up table 102 corresponding to the adjustment mode selected by the adjustment mode selection unit 103 from the prepared look-up table 102, while referring to the RGB data (first data) of the image. 1 image data) is converted into multi-gradation data (second image data) corresponding to the amount of each ink. The look-up table 102 is a table that stores the gradation values of the respective ink amounts for the respective gradation values of RGB. By referring to this table, the other than the improvement ink and the improvement ink can be determined from the three gradation values of RGB. The ink amount gradation value with ink can be determined. By performing data conversion with reference to the lookup table 102 in this way, printing that improves image quality can be performed quickly. Here, the gradations of RGB and ink amount are subdivided into 256 levels, and take values of 0 or more and 255 or less. In this way, high-quality printing can be performed. The RGB gradation and the ink amount gradation are not limited to 256 levels. A higher number of steps, for example, 512 steps, enables higher-quality printing, and a smaller number of steps, for example, 128 steps, reduces the number of recording media required to record the look-up table. The size can be reduced. Note that the first image data is not limited to image data composed of three color components of RGB, and image data of various color systems such as the L * a * b * color system and the XYZ color system. Can be used as the first image data.

  Next, the relationship between the adjustment mode and the lookup table will be described. The lookup table 102 is prepared in correspondence with selectable adjustment modes. For example, when the adjustment mode of the first adjustment mode according to the first embodiment can be selected, a lookup table in which the discharge amounts of the colored ink and the improvement ink have a relationship as shown in FIG. prepare. When the first adjustment mode is selected by the adjustment mode selection unit 103, gloss unevenness can be improved by selecting and referring to the above lookup table. When the normal mode that does not use the improved ink can be selected, a lookup table that has no data about the improved ink or that has a discharge amount of improved ink of 0 can be prepared and used. Further, the same lookup table as that in the first adjustment mode can be used by operating a control unit (not shown) that stops the ejection of the improved ink.

B2. Example 2 of the first adjustment mode:
FIG. 7 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 2 of the first adjustment mode. The meanings of VS, VCL, and VT in FIG. 7 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so that the total discharge amount VT is not less than the first predetermined value A that is not zero. Further, in a region where the value of the colored ink discharge amount VS is larger than the first predetermined value A, the value of the improved ink discharge amount VCL is set to be a value equal to or greater than the second predetermined value B which is not 0. Has been. That is, the total ejection amount VT of all ejected inks in the entire area of the print image is equal to or greater than the first predetermined value A, and the improved ink ejection amount VCL is the second amount in all areas of the print image. It becomes a predetermined value B or more. As a result, even when the gloss of the improved ink and the gloss of the colored ink are different, the difference in gloss can be reduced by ejecting the improved ink over the entire area of the printed image. In the example of FIG. 7, the first predetermined value A is 40% and the second predetermined value B is 5%. These values A and B are the type of ink used and the printing medium. It can be decided according to the type.

B3. Example 3 of the first adjustment mode:
FIG. 8 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 3 of the first adjustment mode. The meanings of VS, VCL, and VT in FIG. 8 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so that the total discharge amount VT is not less than the first predetermined value A that is not zero. Further, in a region where the value of the colored ink discharge amount VS is almost zero, the value of the total discharge amount VT is greater than the first predetermined value A that is not 0 and equal to or less than the third predetermined value C that is not 0. The value of the improved ink discharge amount VCL is set so that The third predetermined value C is a value larger than the first predetermined value A. In a region where the value of the colored ink discharge amount VS is small, particularly in a region where the value of the color ink discharge amount VS is close to 0, the gloss of the print image is determined by the gloss of the print medium. When the gloss of the print medium is weak, the difference in gloss is not sufficiently reduced even if the first ink is ejected by the first predetermined value A in a region where the value of the colored ink ejection amount VS is close to 0%. There is. In such a case, the value of the total discharge amount VT is greater than the first predetermined value A in a region where the value of the color ink discharge amount VS is small, particularly in a region where the value of the color ink discharge amount VS is nearly 0%. The gloss difference can be reduced by setting the improved ink discharge amount VCL so as to be large and less than or equal to the third predetermined value C. In the example of FIG. 8, the first predetermined value A is 20% and the third predetermined value C is 40%. These values A and C are the type of ink used and the print medium. It can be decided according to the type.

B4. Example 4 of the first adjustment mode:
FIG. 9 is a graph illustrating the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 4 of the first adjustment mode. The meanings of VS, VCL, and VT in FIG. 9 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so that the total discharge amount VT is not less than the first predetermined value A that is not zero. Further, in at least a part of the region where the value of the colored ink discharge amount VS is smaller than the first predetermined value A, the value of the total discharge amount VT is larger than the first predetermined value A which is not 0, and 0 The value of the improved ink discharge amount VCL is set so as to be equal to or less than the third predetermined value C. The third predetermined value C is a value larger than the first predetermined value A. Therefore, even when the gloss of the print medium is weak, the value of the total ejection amount VT is larger than the first predetermined value A and smaller than or equal to the third predetermined value C in the region where the colored ink ejection amount VS is small. By setting the improved ink discharge amount VCL, the difference in gloss can be stably reduced. In the example of FIG. 9, the first predetermined value A is 30% and the third predetermined value C is 40%. These values A and C are the type of ink used and the printing medium. It can be decided according to the type.

B5. Example 5 of the first adjustment mode:
FIG. 10 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 5 of the first adjustment mode. The meanings of VS, VCL, and VT in FIG. 10 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so that the total discharge amount VT is not less than a third predetermined value C that is not zero. Therefore, even when the gloss of the print medium is weak, the difference in gloss can be stably reduced regardless of the value of the colored ink discharge amount VS. Furthermore, the value of the improved ink discharge amount VCL is set so that there is no region where the value of the total discharge amount VT decreases as the value of the colored ink discharge amount VS increases. Accordingly, even in a region where the value of the color ink discharge amount VS continuously increases in the printed image, for example, in a gradation region, uneven glossiness can be improved so that boundaries with different glossiness are not noticeable. In the example of FIG. 10, the third predetermined value C described above is 30%, but this value C can be determined according to the type of ink used and the type of print medium.

B6. Example 6 of the first adjustment mode:
FIG. 11 is a graph illustrating the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 6 of the first adjustment mode. The meanings of VS, VCL, and VT in FIG. 11 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so that the total discharge amount VT is not less than the first predetermined value A that is not zero. Further, in a region where the value of the colored ink discharge amount VS is smaller than the first predetermined value A, the improved ink discharge amount VCL is set so that the total discharge amount VT becomes a third predetermined value C which is not zero. Value is set. The third predetermined value C is a value larger than the first predetermined value A. Therefore, even when the gloss of the print medium is weak, by setting the improved ink discharge amount VCL so that the value of the total discharge amount VT becomes the third predetermined value C in the region where the color ink discharge amount VS is small, The difference in gloss can be reduced stably. In the example of FIG. 11, the first predetermined value A is 20% and the third predetermined value C is 40%. These values A and C are the type of ink used and the printing medium. It can be decided according to the type.

B7. Example 7 of the first adjustment mode:
FIG. 12 is a graph illustrating the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 7 of the first adjustment mode. The meanings of VS, VCL, and VT in FIG. 12 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so that the total discharge amount VT is not less than the first predetermined value A that is not zero. Further, in a region where the value of the colored ink discharge amount VS is smaller than the first predetermined value A, the value of the improved ink discharge amount VCL is set to be a fourth predetermined value D that is not zero. The fourth predetermined value D is a value larger than the first predetermined value A. Therefore, even when the gloss of the print medium is weak, the gloss difference is stably reduced by setting the value of the improved ink discharge amount VCL to the fourth predetermined value D in the region where the colored ink discharge amount VS is small. be able to. In addition, in a region where the value of the colored ink discharge amount VS is smaller than the first predetermined value A, the control of the improvement ink discharge amount can be simplified by setting the value of the improvement ink discharge amount VCL to a constant value. You can also In the example of FIG. 12, the first predetermined value A is 20% and the fourth predetermined value D is 40%. These values A and D are the type of ink used and the print medium. It can be decided according to the type.

C. Example of second adjustment mode:
C1. Example 1 of the second adjustment mode 1:
FIG. 13 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 1 of the second adjustment mode. The meanings of VS, VCL, and VT in FIG. 13 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG. The discharge amount of the colored ink is a total value of the discharge amounts of ink that can be used as the colored ink. If the color unevenness varies from ink to ink, the total value can be calculated by applying a weight with a different coefficient for each ink.

  The improved ink ejection amount VCL is a value when the colored ink ejection amount VS is approximately 0% (second ejection amount), and a value when the colored ink ejection amount VS is approximately 100% (first ejection amount). ) Is set to be smaller than. Therefore, uneven color development in a region where the discharge amount of colored ink is large can be improved by the improvement ink. In addition, in a region where the discharge amount VS of colored ink is small and the amount of improvement ink necessary for improving color development is small, the improvement ink discharge amount VCL is reduced so that unnecessary improvement ink is not discharged. ing. Therefore, it is possible to prevent the printing medium from undulating, to prevent the time required for the discharged ink to dry, or to save the amount of improved ink used. Further, the value of the improved ink discharge amount VCL is set so as not to decrease as the value of the colored ink discharge amount VS increases. Therefore, it is possible to eject an appropriate amount of improved ink according to the amount of colored ink.

C2. Example 2 of second adjustment mode:
FIG. 14 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 2 of the second adjustment mode. The meanings of VS, VCL, and VT in FIG. 14 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so as to increase as the value of the colored ink discharge amount VS increases. Further, in a region where the color ink discharge amount VS is smaller than a predetermined value, the improvement ink is set not to be discharged. By avoiding the use of improved ink in areas where the discharge amount VS of colored ink is small and the color unevenness of the ink is inconspicuous, the printing medium undulates and the time required for the discharged ink to dry increases. Can be prevented, and the amount of improved ink used can be saved.

C3. Example 3 of second adjustment mode:
FIG. 15 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 3 of the second adjustment mode. The meanings of VS, VCL, and VT in FIG. 15 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  The value of the improved ink discharge amount VCL is set so that the improved ink is not discharged in a region where the value of the colored ink discharge amount VS is smaller than a predetermined value. By avoiding the use of improved ink in areas where the discharge amount VS of colored ink is small and the color unevenness of the ink is inconspicuous, the printing medium undulates and the time required for the discharged ink to dry increases. Can be prevented, and the amount of improved ink used can be saved. Furthermore, the value of the improved ink discharge amount VCL is set to be a value equal to or greater than the fifth predetermined value E that is not 0 in a region where the value of the colored ink discharge amount VS is greater than the predetermined value. Therefore, when the discharge amount of the improved ink necessary for improving the color development is almost constant regardless of the colored ink discharge amount VS, the color development of the ink can be improved without using an unnecessary improvement ink. it can. Note that the value of the improved ink discharge amount VCL preferably changes smoothly from 0% to the fifth predetermined value E based on the colored ink discharge amount VS. By doing so, it is possible to prevent the boundary between the area where the improved ink is discharged and the area where the improved ink is not discharged from being noticeable. In the example of FIG. 15, the fifth predetermined value E is 5%, but this value E can be determined according to the type of ink used and the type of print medium.

C4. Example 4 of second adjustment mode:
FIG. 16 is a graph for explaining the relationship between the discharge amount of the colored ink and the discharge amount of the improvement ink in Example 4 of the second adjustment mode. The meanings of VS, VCL, and VT in FIG. 16 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  In the range where the colored ink discharge amount VS is equal to or less than the predetermined value F, the improved ink discharge amount VCL is set to zero. In the range where the colored ink discharge amount VS is larger than the predetermined value F, the improved ink discharge amount VCL is set to a constant value E which is not zero. Also by this setting, substantially the same effect as that of the third embodiment shown in FIG. 15 described above can be achieved. However, while the improved ink discharge amount VCL changes stepwise in the fourth embodiment, it gradually increases in the third embodiment of FIG. As a result, depending on the type of print medium, the boundary between the image area in which the improved ink is ejected and the image area in which the improved ink is not ejected may be less noticeable in the third embodiment. In such a case, the third embodiment is more preferable than the fourth embodiment.

  FIG. 17 shows a specific example of the fourth embodiment. Here, the improved ink discharge amount VCL is set to zero only when the colored ink discharge amount VS is 0. When the colored ink discharge amount VS is not 0, the improved ink discharge amount VCL is a constant value E (= 5). %). In the image area where the colored ink ejection amount VS is zero, the improvement of ink coloring is not required, and therefore the improved ink can be saved with the setting shown in FIG.

C5. Example 5 of second adjustment mode:
FIG. 18 is a graph for explaining the relationship between the discharge amount of the colored ink and the discharge amount of the improvement ink in Example 5 of the second adjustment mode. The meanings of VS, VCL, and VT in FIG. 18 and the definitions of the horizontal and vertical axes are the same as those in the graph of FIG.

  In the fifth embodiment, regardless of the value of the colored ink discharge amount VS, the improved ink discharge amount VCL is set to a constant value E of less than 100% which is not zero. According to this setting, it is possible to prevent an undesirable boundary from being generated between the image area where the improved ink is ejected and the image area where the improved ink is not ejected while improving the image quality (particularly, improving the color development). There are advantages.

  FIG. 19 shows an arrangement example of ink dots of improved ink in the fifth embodiment. As described above, in Example 5, the ink dots CLD of the improved ink are uniformly dispersed in the print target area (printable area) on the print medium. In this example, the value E (FIG. 18A) of the improved ink discharge amount is 5%, and the ink dots CLD of improved ink are formed at a rate of one place for 20 pixels PX. As described above, in this specification, the unit of the ink discharge amount is the dot recording rate (the case where ink dots are formed in all pixels is 100%).

  If the ink dots CLD of improved ink are formed on almost all pixels, the color ink may bleed, the time required for the ejected ink to dry may increase, or the print medium may wave. May occur. On the other hand, if the ink dots CLD of the improved ink are uniformly dispersed and arranged in the image print target area as shown in FIG. 19, such a problem can be prevented. Further, one pixel PX at the time of printing is so fine that each pixel cannot be individually identified with the naked eye. Therefore, if the ink dots CLD of the improved ink are uniformly distributed, it is possible to achieve a sufficient image quality improvement effect (particularly, improvement in color development). In order to achieve such an effect, the value E of the improved ink ejection amount VCL may be set to a value within the range of about 1% to about 20%, but in the range of about 1% to about 10%. Values within the range are preferred, and values within the range of about 5% to about 10% are most preferred.

  The arrangement of the ink dots CLD of the improved ink is preferably completely uniformly dispersed as in the example of FIG. 19, but does not have to be completely uniform and may be almost uniform. Such an arrangement of the ink dots CLD of the improved ink is not limited to the fifth embodiment, and is preferably applied to all the other embodiments described above.

  As can be understood from the description of each of the embodiments described above, the range in which the improved ink is ejected may be a part of the entire range that can be taken by the ejection amount of the colored ink. In this way, improved ink can be saved. Further, the range in which the improved ink is ejected can be the entire range that the ejection amount of the colored ink can take. By doing so, it is possible to prevent the boundary between the area where the improved ink is discharged and the area where the improved ink is not from being noticeable.

D. Variation:
The present invention is not limited to the above-described embodiments, and can be implemented in various forms without departing from the gist thereof. For example, the following modifications are possible.

D1. Modification 1:
The printer driver 96 may selectively execute the first adjustment mode and the second adjustment mode described above, or may execute only one of them. However, if the first adjustment mode and the second adjustment mode can be selectively executed, it is possible to improve gloss unevenness and color unevenness with one type of improvement ink. Furthermore, each of the first adjustment mode and the second adjustment mode may be configured by a plurality of adjustment modes. By preparing a plurality of adjustment modes that can be selected in this way, it is possible to respond to user requests in detail and to improve convenience. Further, when there are a plurality of adjustment modes that can be used, it is preferable to prepare a plurality of lookup tables corresponding to the plurality of adjustment modes. By doing so, printing in the selected adjustment mode can be performed quickly.

D2. Modification 2:
The discharge amount of the improved ink can be adjusted based on the total discharge amount of some of the colored inks, not the total discharge amount of all the colored inks that can be used. For example, in the first adjustment mode, the color inks are ejected and the gloss is compared, and the ejection amount of the improved ink can be adjusted based on the ejection amount of only the color ink having a relatively strong gloss. Specifically, gloss unevenness can be improved by adjusting the discharge amount of the improvement ink based on the discharge amount of the K, C, M, and Y inks in the colored ink.

D3. Modification 3:
It is also possible to use an ink that suppresses the gloss of the ejected ink as the improvement ink. In this case, uneven glossiness of the printed image can be improved by using the second adjustment mode. The improved ink ejection amount VCL is a value when the colored ink ejection amount VS is approximately 0% (second ejection amount), and a value when the colored ink ejection amount VS is approximately 100% (first ejection amount). ) Is preferable to be set smaller. Therefore, the gloss of the region where the discharge amount of the colored ink is large can be weakened by the improvement ink, and the difference in gloss from the region where the discharge amount of the color ink is small can be reduced. Further, in a region where the discharge amount of the colored ink is small, the discharge amount of the improvement ink is reduced so that the improvement ink is not discharged more than necessary. Therefore, the usage amount of the improved ink can be saved.

D4. Modification 4:
The ejection amount of the improvement ink can be changed in a stepwise manner in a plurality of stages without being continuously changed according to the ejection amount of the other ink. By doing so, the control of the ejection amount of the improved ink can be simplified.

D5. Modification 5:
In each of the above-described embodiments, printing is performed using a lookup table. However, the present invention is also applicable to a printing method and a printing apparatus that do not use such a lookup table. In the above-described embodiment, the halftone process (dithering process and error diffusion) is also performed for the improved ink CL. However, the improved ink CL is not subjected to the halftone process, and according to the ejection amount VCL. Ink dots of the improved ink CL may be formed according to a predetermined dot arrangement pattern.

D6. Modification 6:
The present invention is also applicable to a drum scan printer. The present invention can be applied not only to a so-called ink jet printer but also to a printing apparatus that prints an image by ejecting ink from a print head. Examples of such a printing apparatus include a facsimile machine and a copying machine.

D7. Modification 7:
In the above embodiment, a part of the configuration realized by hardware may be replaced with software, and conversely, a part of the configuration realized by software may be replaced by hardware. For example, a part of the function of the printer driver 96 (FIG. 1) can be executed by the control circuit 40 (FIG. 3) in the printer 20.

1 is a block diagram showing the configuration of a printing system as an embodiment of the present invention. FIG. 3 is an explanatory diagram illustrating a configuration of a printer. FIG. 3 is a block diagram illustrating a configuration of a control circuit 40 in the printer 20. FIG. 4 is an explanatory diagram showing a nozzle arrangement on the lower surface of the print head. Explanatory drawing explaining the outline of 1st adjustment mode and 2nd adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 1 of the 1st adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 2 of 1st adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 3 of 1st adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of a colored ink and the discharge amount of improvement ink in Example 4 of 1st adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 5 of 1st adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 6 of 1st adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 7 of 1st adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 1 of a 2nd adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 2 of a 2nd adjustment mode. Explanatory drawing explaining the relationship between the discharge amount of colored ink and the discharge amount of improvement ink in Example 3 of 2nd adjustment mode. 14 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 4 of the second adjustment mode. The graph which shows the specific example of Example 4 of 2nd adjustment mode. 10 is a graph for explaining the relationship between the discharge amount of colored ink and the discharge amount of improved ink in Example 5 of the second adjustment mode. Explanatory drawing which shows the example of arrangement | positioning of the ink dot of improvement ink.

Explanation of symbols

20 ... Printer 21 ... CRT
DESCRIPTION OF SYMBOLS 22 ... Paper feed motor 24 ... Carriage motor 26 ... Platen 28 ... Print head 30 ... Carriage 32 ... Operation panel 34 ... Sliding shaft 36 ... Drive belt 38 ... Pulley 39 ... Position sensor 40 ... Control circuit 41 ... CPU
43 ... P-ROM
44 ... RAM
45 ... CG
DESCRIPTION OF SYMBOLS 50 ... Dedicated circuit 52 ... Head drive circuit 54 ... Motor drive circuit 56 ... Connector 60 ... Print head unit 90 ... Computer 91 ... Video driver 95 ... Application program 96 ... Printer driver 97 ... Resolution conversion part 98 ... Ink amount data Conversion unit 99 ... Halftone processing unit 100 ... Print data generation unit 102 ... Look-up table 103 ... Adjustment mode selection unit A ... First predetermined value B ... Second predetermined value C ... Third predetermined value D ... 4th predetermined value E ... 5th predetermined value GP ... Glossy paper NP ... Non-glossy paper

Claims (17)

A printing apparatus that prints an image by ejecting ink onto a print medium,
A print head capable of ejecting at least one kind of colored ink containing a colorant, and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance and light resistance of the printed matter;
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the ink amount to be ejected per one pixel area when printing on glossy paper;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. When the ink amount of the improved ink is set to be less than the predetermined value, and the ink amount of the colored ink is smaller than a predetermined value, the sum of the ink amount of the colored ink and the ink amount of the improved ink is A printing apparatus that sets the ink amount of the improved ink so as to be larger than a minimum value that is not zero of the sum. The printing apparatus according to claim 1,
The adjustment unit is configured so that when the ink amount of the colored ink is smaller than the predetermined value, the ink amount of the improved ink monotonously decreases in accordance with an increase in the ink amount of the colored ink. Set the printing device. The printing apparatus according to claim 1 or 2,
The adjustment unit is configured so that the ink amount of the colored ink and the ink amount of the improvement ink when the ink amount of the colored ink is within at least a part of the range including zero within a range smaller than the predetermined value. A printing apparatus that sets the ink amount of the improved ink so that the sum of the two maintains a predetermined constant value. A printing unit that prints an image by ejecting at least one type of colored ink containing a colorant and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance, and light resistance of the printed material onto a print medium A print control device for generating print data to be supplied to
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the amount of ink ejected per one pixel area when printing on glossy paper;
A print data generation unit that generates print data representing an ejection state of each ink in each pixel on the print medium in accordance with the ink amount of the ink adjusted by the adjustment unit;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. When the ink amount of the improved ink is set to be less than the predetermined value, and the ink amount of the colored ink is smaller than a predetermined value, the sum of the ink amount of the colored ink and the ink amount of the improved ink is A printing control apparatus that sets the ink amount of the improved ink so as to be larger than a minimum value that is not zero of the sum. Printing method for printing using printing apparatus capable of using at least one kind of colored ink containing coloring material and colorless and transparent improved ink for improving at least part of image quality, water resistance and light resistance of printed matter Because
With respect to the amount of ink ejected per area of one pixel when printing on glossy paper, the first ink amount of the improved ink in the area where the colored ink is ejected to almost all pixels is the ejection of the colored ink. When the ink amount of the improved ink is set to be smaller than the second ink amount of the improved ink in a region where there is substantially no ink, and when the ink amount of the colored ink is smaller than a predetermined value, the colored ink A method of printing, comprising: setting the ink amount of the improved ink so that the sum of the ink amount of the improved ink and the ink amount of the improved ink is larger than a non-zero minimum value of the sum. A printing unit that prints an image by ejecting at least one type of colored ink containing a colorant and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance, and light resistance of the printed material onto a print medium A computer program for generating print data to be supplied to
A function of adjusting the ink amount of the improved ink based on the ink amount of the colored ink with respect to the amount of ink discharged per one pixel area when printing on glossy paper;
A function of generating print data representing a discharge state of each ink in each pixel on the print medium in accordance with the adjusted ink amount;
Is a computer program that causes a computer to realize
The adjustment function is such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all the pixels is the second ink amount of the improved ink in a region where the colored ink is hardly ejected. When the ink amount of the improved ink is set to be less than the predetermined value, and the ink amount of the colored ink is smaller than a predetermined value, the sum of the ink amount of the colored ink and the ink amount of the improved ink is A computer program including a function of setting an ink amount of the improved ink so as to be larger than a minimum value that is not zero of the sum. A printing apparatus that prints an image by ejecting ink onto a print medium,
A print head capable of ejecting at least one kind of colored ink containing a colorant, and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance and light resistance of the printed matter;
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the ink amount to be ejected per one pixel area when printing on glossy paper;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. The ink amount of the improved ink is set so as to be less, and the sum of the ink amount of the colored ink and the ink amount of the improved ink does not decrease as the ink amount of the colored ink increases. A printing apparatus that sets the ink amount of the improvement ink to a smaller value as the ink amount of the colored ink is larger. A printing unit that prints an image by ejecting at least one type of colored ink containing a colorant and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance, and light resistance of the printed material onto a print medium A print control device for generating print data to be supplied to
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the amount of ink ejected per one pixel area when printing on glossy paper;
A print data generation unit that generates print data representing an ejection state of each ink in each pixel on the print medium in accordance with the ink amount of the ink adjusted by the adjustment unit;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. The ink amount of the improved ink is set so as to be less, and the sum of the ink amount of the colored ink and the ink amount of the improved ink does not decrease as the ink amount of the colored ink increases. A printing control apparatus that sets the ink amount of the improvement ink to a smaller value as the ink amount of the colored ink is larger. Printing method for printing using printing apparatus capable of using at least one kind of colored ink containing coloring material and colorless and transparent improved ink for improving at least part of image quality, water resistance and light resistance of printed matter Because
With respect to the amount of ink ejected per area of one pixel when printing on glossy paper, the first ink amount of the improved ink in the area where the colored ink is ejected to almost all pixels is the ejection of the colored ink. The ink amount of the improved ink is set to be smaller than the second ink amount of the improved ink in a region where there is almost no ink, and the sum of the ink amount of the colored ink and the ink amount of the improved ink is A printing method comprising a step of setting the ink amount of the improved ink to a smaller value as the ink amount of the colored ink is larger so as not to decrease with an increase in the amount of colored ink. A printing unit that prints an image by ejecting at least one type of colored ink containing a colorant and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance, and light resistance of the printed material onto a print medium A computer program for generating print data to be supplied to
A function of adjusting the ink amount of the improved ink based on the ink amount of the colored ink with respect to the amount of ink discharged per one pixel area when printing on glossy paper;
A function of generating print data representing a discharge state of each ink in each pixel on the print medium in accordance with the adjusted ink amount;
Is a computer program that causes a computer to realize
The adjustment function is such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all the pixels is the second ink amount of the improved ink in a region where the colored ink is hardly ejected. The ink amount of the improved ink is set so as to be less, and the sum of the ink amount of the colored ink and the ink amount of the improved ink does not decrease as the ink amount of the colored ink increases. A computer program comprising a function of setting the ink amount of the improvement ink to a smaller value as the ink amount of the colored ink is larger. A printing apparatus that prints an image by ejecting ink onto a print medium,
A print head capable of ejecting at least one kind of colored ink containing a colorant, and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance and light resistance of the printed matter;
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the ink amount to be ejected per one pixel area when printing on glossy paper;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. The ink amount of the improved ink is set to be less than the predetermined amount, and when the ink amount of the colored ink is smaller than a predetermined value, the ink amount of the improved ink is set to a predetermined constant value that is not zero, A printing apparatus that sets the ink amount of the improved ink to zero when the ink amount of the colored ink is equal to or greater than the predetermined value. A printing unit that prints an image by ejecting at least one type of colored ink containing a colorant and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance, and light resistance of the printed material onto a print medium A print control device for generating print data to be supplied to
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the amount of ink ejected per one pixel area when printing on glossy paper;
A print data generation unit that generates print data representing an ejection state of each ink in each pixel on the print medium in accordance with the ink amount of the ink adjusted by the adjustment unit;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. The ink amount of the improved ink is set to be less than the predetermined amount, and when the ink amount of the colored ink is smaller than a predetermined value, the ink amount of the improved ink is set to a predetermined constant value that is not zero, A print control apparatus that sets the ink amount of the improved ink to zero when the ink amount of the colored ink is equal to or greater than the predetermined value. Printing method for printing using printing apparatus capable of using at least one kind of colored ink containing coloring material and colorless and transparent improved ink for improving at least part of image quality, water resistance and light resistance of printed matter Because
With respect to the amount of ink ejected per area of one pixel when printing on glossy paper, the first ink amount of the improved ink in the area where the colored ink is ejected to almost all pixels is the ejection of the colored ink. When the ink amount of the improved ink is set to be smaller than the second ink amount of the improved ink in a region where there is substantially no ink, and the ink amount of the colored ink is smaller than a predetermined value, the improved ink And a method of setting the ink amount of the improved ink to zero when the ink amount of the colored ink is equal to or greater than the predetermined value. A printing unit that prints an image by ejecting at least one type of colored ink containing a colorant and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance, and light resistance of the printed material onto a print medium A computer program for generating print data to be supplied to
A function of adjusting the ink amount of the improved ink based on the ink amount of the colored ink with respect to the amount of ink discharged per one pixel area when printing on glossy paper;
A function of generating print data representing a discharge state of each ink in each pixel on the print medium in accordance with the adjusted ink amount;
Is a computer program that causes a computer to realize
The adjustment function is such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all the pixels is the second ink amount of the improved ink in a region where the colored ink is hardly ejected. The ink amount of the improved ink is set to be less than the predetermined amount, and when the ink amount of the colored ink is smaller than a predetermined value, the ink amount of the improved ink is set to a predetermined constant value that is not zero, A computer program comprising a function of setting the ink amount of the improved ink to zero when the amount of colored ink is equal to or greater than the predetermined value. A printing apparatus that prints an image by ejecting ink onto a print medium,
A print head capable of ejecting at least one kind of colored ink containing a colorant, and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance and light resistance of the printed matter;
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the ink amount to be ejected per region of one pixel when printing on glossy paper;
A halftone processing unit that performs halftone processing on the ink amount adjusted by the adjustment unit;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. When the ink amount of the improved ink is set to be less than the predetermined value, and the ink amount of the colored ink is smaller than a predetermined value, the sum of the ink amount of the colored ink and the ink amount of the improved ink is A printing apparatus that sets the ink amount of the improved ink so as to be larger than a minimum value that is not zero of the sum. A printing apparatus that prints an image by ejecting ink onto a print medium,
A print head capable of ejecting at least one kind of colored ink containing a colorant, and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance and light resistance of the printed matter;
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the ink amount to be ejected per region of one pixel when printing on glossy paper;
A halftone processing unit that performs halftone processing on the ink amount adjusted by the adjustment unit;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. The ink amount of the improved ink is set so as to be less, and the sum of the ink amount of the colored ink and the ink amount of the improved ink does not decrease as the ink amount of the colored ink increases. A printing apparatus that sets the ink amount of the improvement ink to a smaller value as the ink amount of the colored ink is larger. A printing apparatus that prints an image by ejecting ink onto a print medium,
A print head capable of ejecting at least one kind of colored ink containing a colorant, and a colorless and transparent improvement ink that improves at least part of the image quality, water resistance and light resistance of the printed matter;
An adjustment unit that adjusts the ink amount of the improved ink based on the ink amount of the colored ink with respect to the ink amount to be ejected per region of one pixel when printing on glossy paper;
A halftone processing unit that performs halftone processing on the ink amount adjusted by the adjustment unit;
With
The adjustment unit is configured such that the first ink amount of the improved ink in a region where the colored ink is ejected to almost all pixels is the second ink amount of the improved ink in a region where the colored ink is not ejected. The ink amount of the improved ink is set to be less than the predetermined amount, and when the ink amount of the colored ink is smaller than a predetermined value, the ink amount of the improved ink is set to a predetermined constant value that is not zero, A printing apparatus that sets the ink amount of the improved ink to zero when the ink amount of the colored ink is equal to or greater than the predetermined value.

Images