JP2012040866A - Fluid jetting apparatus and fluid jetting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a background image of high image quality.SOLUTION: This fluid jetting apparatus includes a main image nozzle group which has a predetermined number of nozzles for jetting a fluid for forming a main image; a background image nozzle group which has nozzles in a number greater than the predetermined number for jetting a fluid for forming the background image, and has a first nozzle group located on one side in a predetermined direction and a second nozzle group located on the other side; and a control part for forming dots by jetting the fluid from the main image nozzle group to pixels belonging to a first region on which the main image is formed on a medium, and forming dots by jetting the fluid from the first nozzle group and dots by jetting the fluid from the second nozzle group, one on top of the other, to pixels belonging to a second region on which the image is formed using the fluid for forming the background image on the medium but the main image is not formed.

Description

  The present invention relates to a fluid ejecting apparatus and a fluid ejecting method.

As one of fluid ejecting apparatuses, an ink jet printer (hereinafter referred to as a printer) having a head that ejects ink from nozzles onto a medium is known. Some printers
There is a printer that prints a main image and a background image as a background. For example, in the case of a printer that uses white ink in addition to color ink, a main image using color ink and a background image using white ink can be overlaid and printed (see, for example, Patent Document 1). As a result, an image with good color development can be printed without being affected by the background color of the medium.

JP 2002-38063 A

Normally, ink is applied without any gap in the background image. Therefore, for example, in a printer that repeats a dot forming operation for forming an image while the head moves relative to the medium and an operation for conveying the medium, the number of nozzles for printing the background image is set to print the main image. If the number is the same as the number of nozzles, the density of the background image may be insufficient.
Accordingly, an object of the present invention is to form a background image with high image quality.

A main invention for solving the above problems is that a main image nozzle group, which is a predetermined number of nozzles for ejecting a fluid for forming a main image on a medium, and a fluid for forming a background image of the main image on the medium. A background image nozzle group which is a number of nozzles greater than the predetermined number, and has a first nozzle group located on one side in a predetermined direction and a second nozzle group located on the other side in the predetermined direction. A nozzle group and a control unit that forms an image by ejecting fluid from the nozzle to each pixel defined on the medium to form an image, wherein the first region forms the main image on the medium A dot is formed by ejecting a fluid from the main image nozzle group to the pixels belonging to the area, and an image is formed on the medium by a fluid that forms the background image, and the main image is not formed. A control unit that overlaps and forms dots formed by ejecting fluid from the first nozzle group and dots formed by ejecting fluid from the second nozzle group on the pixels belonging to the second region; A fluid ejecting apparatus characterized by comprising:
Other features of the present invention will become apparent from the description of this specification and the accompanying drawings.

1 is an overall configuration block diagram of a printer. It is a perspective view of a printer. It is a figure which shows the arrangement | sequence of the nozzle provided in the lower surface of a head. It is a figure explaining the printing mode which a printer has. 5A and 5B are diagrams for explaining the overlapping area and the background single area. It is explanatory drawing of the printing pattern 1 in surface printing mode. 7A to 7C are diagrams illustrating the positions of dots formed in the background single region and the overlap region, respectively. 8A and 8B are diagrams showing another method of forming the toning dots of the background image. It is a figure explaining the reserve area | region around an overlap area | region. It is explanatory drawing of the printing pattern 1 in back printing mode. It is explanatory drawing of the printing pattern 2 in surface printing mode. It is explanatory drawing of the printing pattern 3 in surface printing mode. It is explanatory drawing of the printing pattern 4 in surface printing mode. It is explanatory drawing of the printing pattern 5 in surface printing mode. It is sectional drawing of a printer different from the above-mentioned embodiment. 16A and 16B are diagrams for describing a modification example of an image to be printed on a medium.

=== Summary of disclosure ===
At least the following will become apparent from the description of the present specification and the accompanying drawings.

That is, a main image nozzle group that is a predetermined number of nozzles that eject a fluid that forms a main image on a medium, and a number of nozzles that is greater than the predetermined number that ejects a fluid that forms a background image of the main image on the medium A background image nozzle group having a first nozzle group located on one side in a predetermined direction and a second nozzle group located on the other side in the predetermined direction, and defined on the medium A control unit that forms an image by ejecting fluid from the nozzle to each pixel to form an image, wherein the main image nozzle is applied to the pixel belonging to a first region that forms the main image on the medium. A dot is formed by ejecting fluid from a group, and the pixel belonging to a second region that forms an image by the fluid that forms the background image on the medium and does not form the main image, A fluid jet comprising: a control unit that forms dots formed by jetting fluid from the first nozzle group and dots formed by jetting fluid from the second nozzle group. Device.
According to such a fluid ejecting apparatus, it is possible to form an image of the fluid that forms the background image of the second region with a high density, and it is possible to form the background image with high image quality.

In such a fluid ejecting apparatus, in the case where the main image and the background image are overlapped and formed on the medium, in order to form a background image portion that is the background image of the first region and overlaps the main image, Forming dots by ejecting fluid from one of the first nozzle group and the second nozzle group to the pixels belonging to the first region.
According to such a fluid ejecting apparatus, the main image and the background image can be formed to overlap each other.

In this fluid ejecting apparatus, the first nozzle array in which the nozzles that eject the fluid forming the main image are arranged in the predetermined direction, the first nozzle array having the main image nozzle group, and the background image The nozzles that eject the fluid forming the second nozzle array are arranged in the predetermined direction, and are aligned with the first nozzle array in a moving direction that is a direction intersecting the predetermined direction.
A second nozzle array having a nozzle group and the second nozzle group, and fluid is ejected from the nozzle while relatively moving the first nozzle array, the second nozzle array, and the medium in the movement direction. By repeating the dot forming operation and the transport operation of transporting the relative position of the medium to the other side in the predetermined direction with respect to the first nozzle row and the second nozzle row,
The dot forming operation for forming an image and ejecting fluid from the first nozzle group to form dots on the pixels belonging to the second region; and ejecting fluid from the second nozzle group and the second region And the dot forming operation for forming dots in the pixels belonging to.
According to such a fluid ejecting apparatus, it is possible to suppress image quality deterioration due to a transport error.

In the fluid ejecting apparatus, when the main image and the background image are formed on the medium so as to overlap each other, the first background image is formed on the predetermined area of the medium before the main image.
In the mode, the main image is formed by the main image nozzle group which is the nozzle of the first nozzle row aligned with the second nozzle group in the moving direction, and the first region is formed by the first nozzle group. In the second mode in which the background image is formed and the main image is formed prior to the background image with respect to a predetermined area of the medium, the first nozzle row aligned with the first nozzle group in the moving direction. Forming the main image with the main image nozzle group being the nozzle; and
Forming the background image of the first region by the second nozzle group;
According to such a fluid ejecting apparatus, the main image and the background image can be formed in the order according to the mode, and the dot forming operation for forming the main image and the background image of the first region are formed. The dot forming operation can be varied and the drying time can be extended.

In the fluid ejecting apparatus, in the first mode, a background image of the second region is formed by the first nozzle group, the second nozzle group, and the main image nozzle group, and the second mode
In the mode, a background image of the second area is formed by the first nozzle group, the second nozzle group, and the nozzles of the first nozzle row aligned with the second nozzle group in the movement direction.
According to such a fluid ejecting apparatus, a background image of a desired color can be formed.

In the fluid ejecting apparatus, the pixels that form the background image, and the pixels around the pixels belonging to the first region include the first nozzle group and the second nozzle group. Injecting fluid from one nozzle group.
According to such a fluid ejecting apparatus, it is possible to prevent the main image dots and the background image dots from being mixed, and to prevent bleeding of the image.

Further, a main image nozzle group which is a predetermined number of nozzles for ejecting a fluid for forming a main image on the medium, and a number of nozzles larger than the predetermined number for ejecting a fluid for forming a background image of the main image on the medium. A fluid ejection device having a background image nozzle group including a first nozzle group located on one side in a predetermined direction and a second nozzle group located on the other side in the predetermined direction. A fluid ejection method for ejecting a fluid from the nozzle to each pixel defined on the medium, wherein the fluid is ejected from the main image nozzle group to the pixels belonging to a first region that forms the main image on the medium. Forming dots on the medium, and forming pixels on the pixels belonging to a second region that forms an image by a fluid that forms the background image on the medium and that does not form the main image. And dots formed by ejecting a fluid from the nozzle group, and dots formed by ejecting fluid from said second nozzle group, a fluid ejection method and having a be overlaid form, a.
According to such a fluid ejecting method, it is possible to form an image of the fluid that forms the background image of the second region with a high density, and it is possible to form the background image with high image quality.

=== About the printing system ===
Hereinafter, an embodiment will be described with an example of a printing system in which a fluid ejecting apparatus is an inkjet printer (hereinafter referred to as a printer) and a printer and a computer are connected.

FIG. 1 is a block diagram of the overall configuration of the printer 1. FIG. 2 is a perspective view of the printer 1. The computer 60 is communicably connected to the printer 1, and the printer 1
Print data for causing the printer 1 to print an image. The computer 60 is installed with a program (printer driver) for converting image data output from the application program into print data. The printer driver is a CD-ROM or other storage medium (computer-readable storage medium)
Or can be downloaded to a computer via the Internet.

The controller 10 is a control unit for controlling the printer 1. The interface unit 11 is for transmitting and receiving data between the computer 60 and the printer 1. The CPU 12 is an arithmetic processing unit for controlling the entire printer 1. The memory 13 is for securing an area for storing a program of the CPU 12, a work area, and the like. The CPU 12 controls each unit by the unit control circuit 14. The detector group 50 monitors the situation in the printer 1, and the controller 10 controls each unit based on the detection result.

The transport unit 20 feeds the medium S to a printable position, and transports the medium S by a predetermined transport amount in the transport direction during printing.

The carriage unit 30 is for moving the head 41 in a movement direction that intersects the conveyance direction, and includes a carriage 31.

The head unit 40 is for ejecting ink onto the medium S and has a head 41. The head 41 is moved in the movement direction by the carriage 31. A plurality of nozzles, which are ink ejecting portions, are provided on the lower surface of the head 41, and each nozzle is provided with a pressure chamber (not shown) containing ink.

FIG. 3 is a diagram illustrating an arrangement of nozzles provided on the lower surface of the head 41. In addition, the figure is the figure which looked at the nozzle virtually from the upper surface of the head 41. FIG. On the lower surface of the head 41, five nozzle rows in which 180 nozzles are arranged at a predetermined interval D in the transport direction are formed. As shown in the figure, black nozzle row K for ejecting black ink, cyan nozzle row C for ejecting cyan ink, magenta nozzle row M for ejecting magenta ink, yellow nozzle row Y for ejecting yellow ink, and white ink are ejected. White nozzle rows W are arranged in the movement direction. Note that the 180 nozzles in each nozzle row are numbered sequentially from the nozzles on the downstream side in the transport direction (# 1 to # 180).

In such a printer 1, a dot forming operation in which ink droplets are intermittently ejected from the head 41 moving in the movement direction to form dots on the medium, and the medium is conveyed in the conveyance direction with respect to the head 41. The conveyance operation is repeated. By doing so, a dot can be formed by a subsequent dot forming operation at a position on the medium different from the position of the dot formed by the previous dot forming operation, and a two-dimensional image is printed on the medium. can do. The operation in which the head 41 moves once in the moving direction while ejecting ink droplets (one dot forming operation) is referred to as “pass”.

=== About print mode ===
FIG. 4 is a diagram illustrating a printing mode that the printer 1 of the present embodiment has. The printer 1 according to this embodiment has a main image (color image or monochrome image) printed using at least one of the nozzle rows (YMCK) of four colors ink and a white background printed using the white nozzle row W. A printed material is formed on the image. By providing a white background image as the background of the main image, it is possible to print an image with good color development, particularly when the medium is not white. In addition, when the medium is transparent, it is possible to prevent the opposite side of the printed matter from being seen through by printing the main image and the background image in an overlapping manner.

Note that when a background image is printed using only white ink, the color of the white ink itself becomes the color of the background image. However, even in the case of ink called white ink, the color of white is slightly different depending on the ink material. Therefore, a background image having a color different from the color desired by the user may be printed depending on the white ink used. In addition, a background image having a slight chromatic color instead of simple white may be desired. Accordingly, the printer 1 of the present embodiment prints a desired white background image (adjusted white background image) by appropriately using a small amount of four-color ink (YMCK) together with white ink. By doing so, conversely, when the white ink has a slight color, the background image can be printed together with the ink that cancels the color, and the background image can be brought close to an achromatic color. When the printer has light ink (light cyan or light magenta), light ink may be used to adjust the color of the background image.

Then, the printer 1 may store the print data for causing the printer 1 to print a background image using the four colors of ink together with the white ink in advance.
When the user selects a desired background image color by looking at the monitor or computer screen, the printer driver may generate background image print data according to the selected color. .

When the printer 1 forms a printed material in which the main image and the background image are overlaid, the printer 1 forms the printed material in one of the “front printing mode” and the “back printing mode”. The front printing mode is a mode for printing an image so that the main image is viewed from the printing surface side. for that reason,
In the front printing mode, the background image is printed first on a predetermined area of the medium, and the main image is printed on the background image. On the other hand, the reverse printing mode is a mode in which an image is printed so that the main image is viewed from the surface opposite to the printing surface through the medium, and the reverse printing mode is performed when the medium has transparency. . In the reverse printing mode, the main image is printed first on a predetermined area of the medium, and the background image is printed on the main image.

5A and 5B are diagrams for explaining the overlapping area and the background single area. The figure shows a main image and a background image printed in the front printing mode, FIG. 5A is a perspective view of the printed matter, and FIG. 5B is a cross-sectional view of the printed matter. For the following description, the area on the medium where the main image is formed, i.e.
A region formed by overlapping the main image and the background image is referred to as an “overlapping region (corresponding to the first region)”. A region where a background image (an image formed by a fluid forming the background image) is formed on the medium and a main image is not formed is referred to as a “background single region (corresponding to the second region)”. The background image is not limited to a substantially rectangular shape as shown in FIG. For example, a background image bordering the character A as the main image, that is, a range of about several millimeters around the character A may be used as the background image.

=== Print Pattern 1 ===
FIG. 6 is an explanatory diagram of the printing pattern 1 in the front printing mode. In the figure, for simplicity of explanation, the nozzle rows (YMCK) for ejecting the four color inks are collectively referred to as “color nozzle row Co”.
Call it. In the figure, for the sake of simplicity of explanation, the number of nozzles is reduced or the medium conveyance amount is reduced as compared with an actual printer. The number of nozzles belonging to each of the color nozzle row Co and the white nozzle row W is 8 (# 1 to # 8), and the interval between the nozzles arranged in the transport direction in the nozzle row is D.
And

The upper part of FIG. 6 is a diagram showing nozzles used for printing each image. In the front printing mode, the half nozzles # 1 to # 4 on the downstream side in the conveyance direction of the color nozzle row Co are set as “main image nozzle groups” (black circle nozzles) for printing the main image, and the color nozzles The half nozzles # 5 to # 8 on the upstream side in the transport direction of the row Co are set as “toning nozzle groups” (shaded triangular nozzles) for adjusting the white color of the background image. The downstream side of the white nozzle row W in the transport direction (
The half nozzles # 1 to # 4 corresponding to the other side in the predetermined direction are set as “second background nozzle group (corresponding to the second nozzle group)” (white circle nozzle) for printing the background image, “First background nozzle group (corresponding to the first nozzle group)” (white triangle nozzle) for printing the background image on the nozzles # 5 to # 8 on the upstream side in the transport direction of the white nozzle row W. And Therefore, the color nozzle row Co corresponds to the first nozzle row, and the white nozzle row W corresponds to the background image nozzle group and the second nozzle row. In FIG. 6, the number of nozzles (predetermined number) constituting the main image nozzle group is four, and the number of nozzles (more than the predetermined number) constituting the background image nozzle group is eight.

The lower diagram of FIG. 6 is a diagram showing the position of the nozzle in the transport direction in each pass. In the actual printer 1, the medium is transported downstream in the transport direction with respect to the head 41, but the lower diagram in FIG. 6 shows a state in which the head 41 is transported upstream in the transport direction. The printing method shown in FIG. 6 is band printing. Band printing is a printing method in which band images formed in a single pass are arranged in the transport direction. Raster is performed in another pass between raster lines (dot rows along the moving direction) formed in a certain pass. This is a printing method in which no line is formed. Therefore, in the band printing, one medium conveyance amount corresponds to the width of the band image formed in one pass in the conveyance direction.

In the print pattern 1, in the nozzle configuration shown in the upper diagram of FIG.
To form an image while moving in the moving direction, and the medium is half the length of the nozzle row (4D)
The operation of transporting only downstream in the transport direction is repeated. In doing so, for example, FIG.
The position A in the transport direction on the medium shown in the lower diagram first faces the toning nozzle group and the first background nozzle group in pass 1. Thereafter, the medium is transported to the downstream side in the transport direction by half the length (4D) of the nozzle row, so that the position A in the transport direction on the medium faces the main image nozzle group in pass 2. As a result, the main image can be printed on the background image at position A in the transport direction on the medium.

By the way, the position A in the transport direction on the medium faces not only the main image nozzle group (●) but also the second background nozzle group (◯) in pass 2. The main image is printed on the background image in the overlapping area, but the main image is not printed on the background image in the background single area. Therefore, it is possible to form a background image dot in the background single region by the second background nozzle group in pass 2.

Therefore, in the present embodiment, the main image is printed by the main image nozzle group, the background image that overlaps the main image (background image of the overlapping area) is printed by the first background nozzle group, and the background image that does not overlap the main image (background) A background image of a single area) is printed by the first background nozzle group and the second background nozzle group. That is, the number of nozzles per color for printing the main image (in FIG. 6, the color nozzle row Co
The number of white nozzles (FIG. 6) for printing the background image of the background single region rather than the nozzles # 1 to # 4 of FIG.
Then, the nozzles # 1 to # 8) of the white nozzle row W are increased. In addition, the number of white nozzles for printing the background image in the background single region is made larger than the number of white nozzles for printing the background image in the overlapping region (nozzles # 5 to # 8 in the white nozzle row W in FIG. 6).

A raster line constituting the main image is formed in one pass by one nozzle belonging to the main image nozzle group, and a raster line constituting the background image of the overlapping area is formed by one nozzle belonging to the first background nozzle group. The raster lines that form the background image of the background single region are formed by one pass and are formed by two passes by two nozzles belonging to the first background nozzle group and the second background nozzle group, respectively.

By the way, the background image is normally a solid image, and white ink is applied without any gap in order to print the background image. For this reason, if the raster lines constituting the background image of the background single region are formed by only one pass with one nozzle, the density of the background image may be insufficient. In particular, since the background image of the background single region is directly recognized without being superimposed on the main image, it needs to be printed with high density and high image quality.

Therefore, the number of passes for printing the background image of the background single region is made larger than the number of passes for printing the main image and the background image of the overlapping region. Then, the printer 1 of the present embodiment ejects ink from the main image nozzle group to the pixels belonging to the overlapping region in order to form the main image (
In order to form a single dot and to form a background image of the overlapping region, ink is ejected from the first background nozzle group to the pixels belonging to the overlapping region to form a (single) dot, and a background image of the background single region Printing method in which dots formed by ejecting ink from the first background nozzle group and dots formed by ejecting ink from the second background nozzle group are superimposed on pixels belonging to the background single region to form (Fluid ejection method) is performed.

As a result, the background image of the background single region can be printed darkly, and the background image of the background single region can be formed with higher image quality. Note that the background image of the overlapping area is printed so as to overlap the main image, so that it is only necessary to ensure the shielding of the main image, and it is not necessary to print at a higher density than the background image of the background single area.

In addition, when the ink used for printing is, for example, water-based ink (ink containing at least water as a solvent) and the medium used for printing is a medium having water-based ink absorbability, the ink can be ejected per unit area of the medium. The ink amount is limited. If ink is ejected in excess of the amount of ink that can be ejected per unit area of the medium, ink that cannot be absorbed inside the medium overflows on the medium, and ink droplets of different colors that land near the medium are mixed. In combination, bleeding (bleeding) or the like occurs.

The background image of the background single region is not printed over the main image. Therefore, the amount of ink that can be ejected per unit area of the medium to print the background image of the background single area is the amount of ink that can be ejected per unit area of the medium to print the background image of the main image or the overlapping area Can be more. Therefore, even if the background image of the background single region is formed by overlapping the dots from the first background nozzle group and the dots from the second background nozzle group, the ink is ejected in excess of the amount of ink that can be ejected per unit region of the medium. Can be prevented.

Also, assuming that the raster line constituting the background image of the background single area is formed in one pass, if a transport error occurs in the transport operation before that pass, the position of the raster line in the transport direction Will shift. If it does so, the space | interval of the conveyance direction of the raster line formed in the different path | pass will shift | deviate, and the stripe along a moving direction will generate | occur | produce on a background image.

In the present embodiment, in order to form a background image of the background single region, dots are formed by ejecting ink from the first background nozzle group and ink is ejected from the second background nozzle group. Different from the path. Therefore, the background image of the background single region is formed by two passes including the transport operation in between. As a result, even if the position in the transport direction of the dots formed in one pass is shifted due to a transport error, the image quality deterioration of the background image can be suppressed if the positions in the transport direction of the dots formed in the other pass are equal. .

In summary, in the printer 1 of the present embodiment, when the background image is printed before the main image in a predetermined area of the medium as in the front printing mode (corresponding to the first mode), the main image is printed. The first background nozzle group that prints the background image from the main image nozzle group to be used is the nozzle on the upstream side in the transport direction. That is, the main image is formed by the main image nozzle group which is the nozzle of the color nozzle row Co aligned in the moving direction with the second background nozzle group on the downstream side in the transport direction, and the first image on the upstream side in the transport direction.
A background image of the overlapping region is formed by the background nozzle group. By doing so, the pass in which the background image is printed by the first background nozzle group and the pass in which the main image is printed by the main image nozzle group can be made different for a predetermined area of the medium. As a result, for a given area of the medium,
The drying time from when the background image is printed to when the main image is printed can be made relatively long, and bleeding of the image can be prevented.

Then, the second background nozzle group arranged in the moving direction of the main image nozzle group and the head 41 is used for printing the background image of the background single region that does not overlap the main image. As a result, the background image of the background single region can be printed with a high density. That is, in the present embodiment, the background image of the background single region is printed by effectively using the second background nozzle group arranged in the movement direction with the main image nozzle group. Second
The white nozzle row W is printed by printing the background image of the background single region using the background nozzle group.
All the nozzles belonging to the above are used for printing, and deviation in the usage frequency of the nozzles is suppressed, and as a result, the life of the head 41 can be extended. In addition, it is possible to prevent clogging of ink due to the non-use of the nozzle for a long period of time and sedimentation of the color material that is the ink composition, and it is possible to suppress deterioration in the image quality of the background image.

In this embodiment, in order to adjust the white color of the background image, the first background nozzle group and the toning nozzle group aligned in the moving direction of the head 41 are used for printing. Therefore, since all the nozzles are used for printing in the color nozzle row Co as well as the white nozzle row W, it is possible to prevent uneven use of nozzles, clogging, and ink color material settling.

Further, the ratio of the color ink constituting the background image is smaller than the ratio of the white ink. However, in order to reduce the graininess of the color ink in the background image, it is preferable to disperse the dots of the color ink as uniformly as possible on the background image. That is, the color ink density (dot density) per unit area of the background image is made smaller than the white ink density (dot density) per unit area of the background image. Therefore, as shown in FIG. 6, it is preferable to make the number of nozzles belonging to the first background nozzle group equal to the number of nozzles belonging to the toning nozzle group, so that the dots by the toning nozzle group have a small size. However, the present invention is not limited to this, and the number of nozzles belonging to the toning nozzle group may be smaller than the number of nozzles belonging to the first background nozzle group.

Moreover, in order to lengthen the drying time of the image printed previously with respect to the predetermined area | region of a medium, you may provide an unused nozzle between the 1st background nozzle group and the main image nozzle group. By doing so,
A path where the image is not printed (pass where the unused nozzle faces the medium) can be provided between the path where the background image is printed on the predetermined area of the medium and the path where the main image is printed. The time can be further increased. In addition, the length in the transport direction of the region to which the unused nozzle belongs is preferably an integral multiple of the medium transport amount. By doing so, the number of passes between the pass for printing the background image and the pass for printing the main image can be made constant throughout the entire image, and uneven density of the image can be prevented.

Hereinafter, a specific dot forming method will be described.
7A to 7C are diagrams illustrating the positions of dots formed in the background single region and the overlap region, respectively. In the figure, the dotted squares are “pixels” which are unit areas on the medium on which one dot is formed. As a horizontal position, a smaller number (1 from the left pixel in the moving direction)
2, 3,..., And the column number is a smaller number (L 1) in order from the downstream pixel in the transport direction.
, L2, L3 ...). The horizontal position of pixels 1 to 4 and 8 to 11 are “background single region”.
And pixels having horizontal positions 5 to 7 are pixels belonging to the “overlapping region”. Also,
The pixels whose column numbers are L1 to L4 are pixels belonging to the region of the position A in the transport direction, and the column numbers are L5 to L5.
Let L8 be a pixel belonging to the region at position B in the transport direction.

In FIG. 7, it is assumed that the print data instructs to form dots in all the pixels. In addition, it is assumed that the background image of the overlapping area is formed only by white ink without adjusting the white color by the four-color ink. Therefore, it is assumed that dots by the toning nozzle group are formed only in the background single region. In FIG. 7, the dots formed by the first background nozzle group are indicated by “Δ (open triangle)”, and the dots formed by the second background nozzle group are indicated by “◯ (open circle)”. The dots formed by the main image nozzle group are indicated by “● (
It is assumed that the dots formed by the toning nozzle group are not shown.

First, in pass 1 shown in FIG. 7A, the first background nozzle group and the toning nozzle group face the region at position A in the transport direction on the medium. The first background nozzle group is a pixel belonging to the region of the position A, and forms dots (Δ) in all pixels belonging to the background single region and the overlapping region. Also,
The toning nozzle group is a pixel belonging to the region of the position A, and forms dots (not shown) in all the pixels belonging to the background single region.

Next, when the medium is transported to the downstream side in the transport direction by half the length of the nozzle row, as shown in FIG. 7B, the main image nozzle group and the second background nozzle group are located at the position A in the transport direction on the medium. The toning nozzle group and the first background nozzle group are opposed to the area at the position B in the transport direction on the medium. The toning nozzle group and the first background nozzle group that face the region of the position B in the transport direction form dots as in FIG. 7A. The main image nozzle group is a pixel belonging to the region of the position A in the transport direction and forms dots (●) in all the pixels belonging to the overlapping region. On the other hand, the second background nozzle group is a pixel belonging to the region of the position A in the transport direction, and forms dots (◯) in all the pixels belonging to the background single region. As a result, in the pixel belonging to the background single region at the position A in the transport direction, the dot (Δ) formed by the first background nozzle group in pass 1 and the dot (◯) formed by the second background nozzle group in pass 2 And overlap.

After that, when the medium is transported to the downstream side in the transport direction by half the length of the nozzle row, as shown in FIG. 7C, the main image nozzle group and the second background nozzle group are in the region of the position B in the transport direction on the medium. Opposite. Then, the main image nozzle group and the second background nozzle group have dots (•• ○) as in FIG. 7B.
). As a result, in the pixel belonging to the background single region at the position B in the transport direction, the dot (Δ) formed by the first background nozzle group in pass 2 and the dot (◯) formed by the second background nozzle group in pass 3 And overlap. In this way, the background image of the background single region at the positions A and B in the transport direction can be printed darkly, and the background image of the background single region can be formed with high image quality.

8A and 8B are diagrams showing another method of forming the toning dots of the background image. In the printing method of FIG. 7 described above, the nozzles of the color nozzle row Co on the upstream side in the transport direction from the second background nozzle group are used as the toning nozzle group. Therefore, after the toning dots are formed by the toning nozzle group, the white ink dots are formed on the toning dots. In this case, there is a possibility that the color tone of the toning dots is canceled and a background image of a desired color cannot be printed. Therefore, the main image nozzle group arranged in the movement direction with the second background nozzle group may play the role of the toning nozzle group. That is, in the front printing mode, the background image of the background single region is formed by the first background nozzle group, the second background nozzle group, and the main image nozzle group.

Specifically, as shown in FIG. 8A, first, in pass 1, the first background nozzle group forms white ink dots (Δ) on the pixels in the background single region. Next, after the medium is transported by half the length of the nozzle row, as shown in FIG. 8B, in pass 2, the second background nozzle group forms white ink dots (◯) on the pixels in the background single region. Meanwhile, the main image nozzle group forms toning dots (●) on pixels in the background single region.

By doing so, the white ink dots are not formed on top of the toning dots,
The color tone of the toning dots can be prevented from being canceled, and a background image of a desired color can be formed. Also, the white ink dot (◯) and the toning dot (●) that are formed last in the background single area can be formed in the same pass, so the white ink dot and the toning dot are mixed. In addition, it is possible to improve the graininess of dots in the background image of the background single region.

FIG. 9 is a diagram for explaining a spare area around the overlapping area. In the printing method of FIG.
The background is a single region from the pixels adjacent to the pixels on which the main image is printed (for example, the horizontal positions are the fourth and eighth pixels). That is, the overlapping area and the background single area are adjacent to each other. Then, dots are formed by the second background nozzle group (◯) aligned with the main image nozzle group in the moving direction in a pass in which the main image is printed on a pixel adjacent to the pixel on which the main image is printed. Usually, dots larger than the area of one pixel at the maximum are formed. In particular, since the background image is a solid image, dots larger than the area of one pixel are formed. Therefore, as in the printing method of FIG. 7, when dots are formed in the same pass on the pixels on which the main image is printed and on the pixels adjacent to the pixels on which the main image is printed, the dots for the background image and the main image As a result, the printed image (especially the outline of the main image) is blurred.

Therefore, a “preliminary area” is provided around the pixels on which the main image is printed, that is, around the pixels belonging to the overlapping area. Then, similarly to the background image of the overlapping area, the background image of the spare area is formed only by the first background nozzle group whose position in the transport direction is shifted from that of the main image nozzle group.
In other words, pixels that form a background image and that surround the pixels belonging to the overlapping region are filled with ink from one of the first background nozzle group and the second background nozzle group according to the print mode. To spray.

By doing so, dots for the background image are formed in pixels adjacent to the pixels on which the main image is printed, in a different path from the path in which the main image dots are formed. Therefore, it is possible to prevent the printed image from bleeding due to the color mixing of the background image dots and the main image dots. In FIG. 9, one pixel around the overlapping area is used as a spare area. However, the present invention is not limited to this, and a plurality of pixels around the overlapping area may be used as a spare area.

FIG. 10 is an explanatory diagram of the print pattern 1 in the reverse printing mode. In reverse printing mode,
Contrary to the front printing mode (FIG. 6), as shown in the upper diagram of FIG. 10, the half nozzles (# 1 to # 4) on the downstream side in the transport direction of the color nozzle row Co are used as the toning nozzle group, and the color The half nozzles (# 5 to # 8) on the upstream side in the transport direction of the nozzle row Co are defined as a main image nozzle group. As for the white nozzle row W, as in the front printing mode, half of the nozzles (# 1 to # 1 on the downstream side in the transport direction).
# 4) is the second background nozzle group, and the half nozzles (# 5 to # 8) on the upstream side in the transport direction are the first background nozzle group. That is, in the reverse printing mode (corresponding to the second mode), the main image is formed by the main image nozzle group which is the nozzle of the color nozzle row Co aligned with the first background nozzle group on the upstream side in the transport direction and the transport direction. A background image of the overlapping region is formed by the second background nozzle group on the downstream side.

By doing so, as shown in the lower diagram of FIG. 10, the position A in the transport direction on the medium first faces the main image nozzle group and the first background nozzle group in pass 1. At this time, the main image nozzle group forms dots for the main image on the pixels belonging to the overlapping area, and the first background nozzle group forms dots for the background image on all the pixels in the background single area. Thereafter, the medium is transported to the downstream side in the transport direction by half the length (4D) of the nozzle row, so that the position A in the transport direction on the medium is the toning nozzle group and the second background nozzle group in pass 2 Opposite. At this time, the toning nozzle group forms dots in pixels belonging to the background single region, and the second background nozzle group forms dots in pixels belonging to the background single region and the overlapping region. As a result, a background image is printed on the main image,
In the background image of the background single region, the dots by the first background nozzle group and the dots by the second background nozzle group are formed in an overlapping manner.

As described above, in this embodiment, in order to form a background image of the overlapping region, one of the first background nozzle group and the second background nozzle group is applied to the pixels belonging to the overlapping region according to the print mode. Ink is ejected from the nozzle group to form dots. By doing so, the main image and the background image can be formed in an overlapping manner. In addition, the background image and the main image of the overlapping area can be formed by different passes.

Note that, in the reverse printing mode, the overlapping region is formed by the first background nozzle group, the second background nozzle group, and the nozzles of the color nozzle row Co aligned in the moving direction with the second background nozzle group (the toning nozzle group in FIG. 10). It is preferable to form a background image. By doing so, it is possible to prevent the color tone of the toning dots from being canceled, and a background image of a desired color can be formed. Also, since white ink dots and toning dots can be overlapped and formed in the same pass, the white ink dots and toning dots are mixed, resulting in the granularity of dots in the background image of the background single area. Sex can be improved.

=== Print pattern 2 ===
FIG. 11 is an explanatory diagram of the printing pattern 2 in the front printing mode. The print pattern 2 has the same nozzle configuration as that of the print pattern 1 (FIG. 6). That is, the half nozzles (# 1 to # 4) on the downstream side in the transport direction of the color nozzle row Co are set as the main image nozzle group, and the half nozzles (# 5 to # 8) on the upstream side in the transport direction are set as the toning nozzle group. To do. The half nozzles (# 1 to # 4) on the downstream side in the transport direction of the white nozzle row W are set as the second background nozzle group, and the half nozzles (# 5 to # 8) on the upstream side in the transport direction are the first background nozzles. A group.

The printing pattern 2 is a printing method (interlace printing) in which raster lines are formed in another pass between raster lines formed in a certain pass. For example, nozzle # in pass 1
A raster line for the background image is formed in pass 2 and pass 3 between the raster lines for the background image formed in 7, # 8. Therefore, in the printing pattern 2, the medium conveyance amount is shortened to 4D / 3 as compared with the printing pattern 1 (band printing) shown in FIG. In the printing pattern 2 that is interlaced printing, the printing resolution in the transport direction is higher than in the printing pattern 1 that is band printing.

Also in the print pattern 2, as in the print pattern 1, for the pixels belonging to the background single region, the dot (Δ) by the first background nozzle group and the dot (◯ by the second background nozzle group)
). By doing so, the background image of the background single region can be printed at a high density, and the background image of the background single region can be formed with high image quality.

=== Print Pattern 3 ===
FIG. 12 is an explanatory diagram of the printing pattern 3 in the front printing mode. The print pattern 3 has the same nozzle configuration as that of the print pattern 1 (FIG. 6). The printing pattern 3 is a printing method in which two nozzles of each nozzle group are opposed to one pixel, and is so-called overlap printing. Therefore, in the print pattern 3, the medium conveyance amount is shortened to 2D / 3 as compared with the print pattern 1 and the print pattern 2.

For example, on the raster line immediately below the print start position, nozzle # 7 of the first background nozzle group and the toning nozzle group in pass 2 and nozzle # 5 of the first background nozzle group and the toning nozzle group in pass 5 The nozzle # 3 of the main image nozzle group and the second background image nozzle group in pass 8 and the nozzle # 1 of the main image nozzle group and the second background image nozzle group in pass 11 are allocated.

Therefore, in the print pattern 3, not only the background image of the background single region but also the raster lines constituting the background image and the main image of the overlapping region can be formed by two nozzles. When dots are formed by overlapping two nozzles, the background image and main image of the overlapping area can be printed at a high density. When dots by two nozzles are formed at different positions in the moving direction, defective nozzles are printed. It is possible to suppress the image quality deterioration due to.

Further, the raster line constituting the background image of the background single region can be formed by four nozzles. For example, when all the dots by four nozzles assigned to the raster line constituting the background image of the background single region are overlapped, the background image of the background single region can be formed at a higher density. In addition, a dot formed by one of the two nozzles of the first background nozzle group and a dot formed by one of the two nozzles of the second background nozzle group may be formed on some of the pixels arranged in the moving direction. In another part of the pixels formed in an overlapping manner and arranged in the moving direction, a dot formed by the other of the two nozzles of the first background nozzle group and the other of the two nozzles of the second background nozzle group Alternatively, the dots formed by the nozzles may be overlapped.

As described above, in the print pattern 3, a maximum of four dots can be overlapped to form a background image of the background single region. However, when an ink-absorbing medium is used, the amount of ink that can be ejected per unit area of the medium is limited. Therefore, it is preferable to print the background image of the background single region so as not to exceed the amount of ink that can be ejected per unit region of the medium. When ink that is cured when irradiated with ultraviolet rays (UV ink) is used, the amount of ink that can be ejected per unit area of the medium is not limited, so that a background image of a single background area is formed by overlapping four dots. There is no problem.

=== Print Pattern 4 ===
FIG. 13 is an explanatory diagram of the printing pattern 4 in the front printing mode. In the print pattern 4, the number of nozzles belonging to the first background nozzle group shifted from the main image nozzle group in the transport direction is made smaller than the number of nozzles belonging to the main image nozzle group. In FIG. 13, the number of nozzles belonging to each of the color nozzle row Co and the white nozzle row W is six. In the color nozzle row Co, four nozzles (# 1 to # 4) on the downstream side in the transport direction are set as a main image nozzle group, and two nozzles (# 5 to # 6) on the upstream side in the transport direction are adjusted. Let it be a color nozzle group. In the white nozzle row W, four nozzles (# 1 to # 4) on the downstream side in the transport direction are set as the second background nozzle group, and two nozzles (# 5 to # 6) on the upstream side in the transport direction are set. A first background nozzle group is assumed.

In this case, for example, nozzle # 5 of the first background nozzle group and toning nozzle group in pass 2 and the main image nozzle group and second background image nozzle group in pass 5 are placed on the raster line immediately below the print start position. Nozzle # 3 and nozzle # 1 of the main image nozzle group and the second background image nozzle group of pass 8 are
Assigned. Therefore, in the print pattern 4, as in the print pattern 3 (FIG. 13), the raster line constituting the main image can be formed by the two nozzles (●), and the deterioration of the image quality of the main image is suppressed. Can do.

On the other hand, since the number of nozzles belonging to the first background nozzle group is reduced from the number of nozzles belonging to the main image nozzle group, the number of nozzles (Δ) of the first background nozzle group assigned to one raster line is one. However, the background image of the single background region can be formed using not only the nozzles of the first background nozzle group but also the nozzles (◯) of the second background nozzle group. Therefore, even if the number of nozzles belonging to the first background nozzle group is reduced from the number of nozzles belonging to the main image nozzle group, the raster line constituting the background image of the background single region is formed by three nozzles (Δ · ○). can do.

For example, when all the dots by three nozzles assigned to the raster line constituting the background image of the background single region are overlapped, the background image of the background single region can be printed at a higher density. In addition, dots formed by the nozzles of the first background nozzle group and dots formed by one nozzle of the second background nozzle group are formed on a part of the pixels arranged in the moving direction so as to overlap with another part of the pixels arranged in the moving direction. The dots by the other nozzle of the second background nozzle group may be formed.

Further, since the background image of the overlapping area is formed only by the nozzles belonging to the first background nozzle group, the number of nozzles that can form a raster line constituting the background image of the overlapping area is one. However,
Since the background image of the overlapping area is formed so as to overlap with the main image, it is only necessary to ensure the shielding of the main image, and there is no problem even if it cannot be printed at a high density.

Thus, in the print pattern 4, the number of nozzles belonging to the first background nozzle group is reduced from the number of nozzles belonging to the main image nozzle group, so that the number of nozzles belonging to the nozzle row can be reduced.
In other words, the number of nozzles belonging to the main image nozzle group can be increased by the amount corresponding to the reduction of the number of nozzles belonging to the first background nozzle group.

=== Print Pattern 5 ===
FIG. 14 is an explanatory diagram of the printing pattern 5 in the front printing mode. FIG. 14 is a diagram illustrating a printing method when the nozzle interval D in the transport direction in the nozzle row is short. The print pattern 5 has the same nozzle configuration as that of the print pattern 1 (FIG. 6).

When printing using the head 41 having a short nozzle interval D, a raster line is formed in another pass between raster lines formed in a certain pass as in the print pattern 2 to the print pattern 4 (FIGS. 11 to 13). Can be printed without increasing the printing resolution in the transport direction. Further, in the printing pattern 5, the medium conveyance amount is shortened compared to the printing pattern 1 (FIG. 6). Therefore, similarly to the printing pattern 3, the raster lines constituting the main image and the background image can be formed by two nozzles, so that printing can be performed at a high density and image quality deterioration due to defective nozzles can be suppressed. it can.

The description of the print patterns 1 to 5 in which the main image and the background image are overprinted is finished. It is to be noted that an image is formed during the forward path in which the head 41 moves to one side of the moving direction,
It is assumed that bidirectional printing for forming an image may be performed even during the return pass when moving to the other side of the moving direction, or unidirectional printing for forming an image only during either the forward pass or the return pass.

In this embodiment, the printer driver ejects fluid from the main image nozzle group to the pixels in the overlapping region to form dots, and ejects fluid from the first background nozzle group to the pixels in the background single region. Printing data is created to overlap the dots to be formed and the dots formed by ejecting fluid from the second background nozzle group. Based on the print data, the controller 10 of the printer 1 controls the head unit 40 and the like. Accordingly, the controller 10 of the printer 1 and the computer 60 on which the printer driver is installed correspond to a “control unit”, and a printing system in which the printer 1 and the computer 60 are connected is a “fluid ejecting apparatus”.
It corresponds to. However, the present invention is not limited to this, and the controller 10 of the printer 1 may play the role of a printer driver. In this case, the controller 10 of the printer 1 corresponds to a “control unit”, and the printer 1 alone serves as a “fluid ejecting device”. Equivalent to.

=== Modification ===
FIG. 15 is a cross-sectional view of the printer 2 different from the above-described embodiment. Up to this point, as shown in FIG. 2, the printer 1 in which the operation of forming an image while the head 41 (FIG. 3) moves in the movement direction and the operation of conveying the medium in the conveyance direction are repeated alternately is taken as an example. However, it is not limited to this. As shown in FIG. 15, the transport roller 2 is placed under the fixed heads 41.
The printer 2 that transports the medium S by the transport belt 22 rotated by 1 may be used.

In the printer 2 of the modified example, the first white head 41 (W1) that ejects white ink, the yellow head 41 (Y) that ejects yellow ink, and the magenta head 41 that ejects magenta ink (in order from the upstream side in the transport direction). M) Cyan head 4 for ejecting cyan ink
1 (C), a black head 41 (K) for ejecting black ink, and a second white head 41 (W2) for ejecting white ink are arranged.

In such a printer 2, when the main image and the background image are overprinted in the surface printing mode, first, the first white head 41 (W1) first forms dots that constitute the background image of the background single region and the overlap region. . Thereafter, each head 41 of four-color ink forms all the dots constituting the main image. Finally, the dots formed by the second white head 41 (W2) are formed on the dots forming the background image of the background single region formed by the first white head 41 (W1).

On the contrary, when the main image and the background image are printed in the reverse printing mode, first, the first white head 41 (W1) forms dots constituting the background image of the background single region. Thereafter, each head 41 of four-color ink forms all the dots constituting the main image. Finally, the second white head 41 (W2) forms dots that constitute the background image of the overlapping area, and
The dots formed by the second white head 41 (W2) are formed on the dots constituting the background image of the background single region formed by the first white head 41 (W1).
By doing so, the main image and the background image can be overlaid and printed in the order according to the mode, and the background image of the background single region can be printed at a high density.

Further, in the above-described embodiment, an example is given in which a background image in which white color is adjusted by using four-color ink (YMCK) as appropriate for white ink is described. A background image may be printed. In addition, the background image is not limited to white, and the background image may be printed with color inks other than white ink (for example, metallic ink). In the above-described embodiment, the main image is printed using only four-color ink (YMCK). However, the present invention is not limited to this, and the main image is printed using white ink (ink for a background image) together with four-color ink. May be.
By printing the main image by adding the white ink to the four color inks, it is possible to print an image that reproduces the color with high brightness and high saturation.

In the above-described embodiment, the main image and the background image are overprinted, but the present invention is not limited to this. For example, the background image may be printed only around the main image. That is, only the background image is printed in the background single area shown in FIG. 5B, and only the main image is printed in the overlapping area. Also in this case, in order to print the background image of the background single region, the dots formed by the first background nozzle group positioned on the upstream side in the transport direction and the dots formed by the second background nozzle group positioned on the downstream side in the transport direction are overlapped. To do.
As a result, the background image can be printed at a high density, and the background image can be formed with high image quality.

16A and 16B are diagrams for describing a modification example of an image to be printed on a medium. In the above-described embodiment, an example in which an image (FIG. 5) in which a main image and a background image are overlaid is given.
Although white ink is used only for printing a background image, the present invention is not limited to this. For example, as shown in FIG. 16A, together with an image in which the main image and the background image are superimposed, an image using white ink (corresponding to an image using white characters and fluid forming the background image in the figure) may be printed on the medium. .
In particular, an image using white ink may be printed on a colored medium or a transparent medium.

Similarly to the background image of the background single region, this white ink image is not printed over the main image. Therefore, the main image nozzle group (for example, nozzles # 1 to # 4 of the color nozzle row Co in FIG. 6).
) And the first background nozzle group (for example, nozzles # 5 to # 5 in the white nozzle row W of FIG.
In addition to # 8), the second background nozzle group (for example, nozzles # 1 to # 4 in the white nozzle row W in FIG. 6) aligned with the main image nozzle group in the moving direction is used to print an image with white ink. be able to.

Therefore, similarly to the background image of the background single region, an image with white ink is formed in two passes, and pixels belonging to a region (corresponding to the second region) in which an image with white ink is formed are assigned to the first background. The dots of the nozzle group and the dots of the second background nozzle group are formed so as to overlap each other. That is, an image formed by the first background nozzle group and an image formed by the second background nozzle group are formed to overlap each other. By doing so, the image by white ink can be printed darkly. In addition, raster lines constituting an image with white ink can be formed by two different nozzles, and image quality degradation due to defective nozzles can be suppressed. That is, an image with white ink can be formed with high image quality.

In particular, when printing an image with white ink on a medium of dark color (eg, black), the image density (white density) is thin and the image visibility is reduced by only printing in one pass. There is a risk of it. Therefore, as in this modification, the white image by the first background nozzle group and the white image by the second background nozzle group are formed in an overlapping manner, thereby improving the visibility of the image.

Also, when the image that overlays the main image and the background image and the image with white ink are aligned in the movement direction,
That is, when two images are printed in the same pass, the amount of transport of the medium must be set to, for example, half the length of the nozzle row in accordance with the image that overlaps the main image and the background image.
However, as in this modification, by printing an image with white ink using the first background nozzle group and the second background nozzle group, the white nozzle row W can be used effectively, and the image has high image quality. Can be printed on.

In the above-described embodiment, the background image is larger than the main image (FIG. 5), that is,
Although the example which prints the image which has the site | part of the background image (background image of a background single area | region) which does not overlap with a main image is given, it is not restricted to this. As shown in FIG. 16B, an image in which the main image and the background image have the same size and an image using white ink may be printed on a medium.

=== Other Embodiments ===
Each of the above embodiments is described mainly for a printing system having an ink jet printer, but includes disclosure of a printing method and the like. The above-described embodiments are for facilitating understanding of the present invention, and are not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof.

<About white>
In the present specification, the term “white” is not limited to white in the strict sense that is the surface color of an object that reflects 100% of all wavelengths of visible light. It shall include a color called white. “White” means, for example, (1) Color measurement mode: Spot color measurement, Light source: D50, Backing: Black, Print medium: Measured with transparent film, using x-rite colorimeter eye-one Pro If it is colored, the label in the Lab system is on the a ^* b ^* plane within the circumference of the radius 20 and inside thereof, and L ^* is a color within the hue range represented by 70 or more, or (2) Minolta When using the colorimeter CM2022 manufactured by the company with color measurement in the measurement mode D502 ° field of view, SCF mode, and white background, the label in the Lab system is on the circumference of the radius 20 on the a ^* b ^* plane and inside it. And L ^* is a color within the hue range represented by 70 or more, or (3) the color of the ink used as the background of the image as described in JP-A-2004-306659, and used as the background If it is possible, it is not limited to pure white.

<About the printer>
In the above-described embodiment, the printer 1 that repeats the operation of forming an image on a medium while moving the head 41 in the movement direction and the operation of conveying the medium in the conveyance direction with respect to the head 41 is taken as an example. Not limited to this. For example, for continuous paper conveyed to the print area,
A medium in which an image is formed by repeating an operation of forming an image while moving a head unit having a plurality of heads in the medium conveyance direction and an operation of moving the head unit in the paper width direction, and the medium that has not yet been printed A printer that transports the portion to the printing area and forms an image again may be used.

Further, the fluid ejection method from the nozzle may be a piezo method in which a fluid is ejected by applying a voltage to the driving element (piezo element) to expand and contract the pressure chamber, or bubbles are generated in the nozzle using a heating element. It may be a thermal system in which the fluid is generated and the fluid is ejected by the bubbles.

<About fluid ejection device>
In the above-described embodiment, the printer 1 has been described. However, the present invention is not limited to this. Other fluids other than ink (liquids, liquids in which particles of functional materials are dispersed, fluids such as gels) Or a fluid ejecting apparatus that ejects the body). For example, color filter manufacturing apparatus, dyeing apparatus, fine processing apparatus, semiconductor manufacturing apparatus, surface processing apparatus, three-dimensional modeling machine, gas vaporizer, organic EL manufacturing apparatus (especially polymer EL manufacturing apparatus), display manufacturing apparatus, film formation You may apply the technique similar to the above-mentioned embodiment to the various apparatuses which applied inkjet technology, such as an apparatus and a DNA chip manufacturing apparatus. These methods and manufacturing methods are also within the scope of application.

<About ink and media>
As a (recording) medium used in the printer 1, an ink that cures when irradiated with ultraviolet rays (UV
Ink) may be used, and when UV ink is used, it is not necessary to be a medium having ink absorbability. However, an irradiator for irradiating ultraviolet rays is required.

In addition, examples of the (recording) medium used in the printer 1 include a medium having ink absorbability. Ink absorbed in a medium having ink absorbability includes “water-based ink” that contains at least water as a solvent. Examples of the color ink (YMC) and black ink (K) having such a composition include, for example, JP-A-2008-81693 and JP-A-2005-105135.
And inks described in JP-A No. 2003-292834. Examples of the white ink (W) include inks described in JP2009-138078A and JP2009-137124A.

The medium that absorbs water-based ink includes, for example, a medium using a base material that absorbs ink, such as paper and cloth, an ink absorption layer that absorbs ink on a base material that absorbs ink or a base material that does not absorb ink. There is a medium provided. Examples of the material of the base material include polyester film, polyolefin film, resin film such as polyvinyl chloride, paper such as plain paper, coated paper, or tracing paper, resin-coated paper, or synthetic paper. . In addition,
Examples of the medium having transparency include media described in JP-A-2009-925, JP-A-9-99634, and JP-A-9-208870.

1 printer, 2 printer,
10 controller, 11 interface section,
12 CPU, 13 memory, 14 unit control circuit,
20 transport unit, 30 carriage unit, 31 carriage,
40 head units, 41 heads, 50 detector groups,
60 computers

Claims (7)

A main image nozzle group that is a predetermined number of nozzles that eject a fluid that forms a main image on a medium;
A background image nozzle group, which is a number of nozzles greater than the predetermined number for ejecting a fluid that forms a background image of the main image on the medium, and the first nozzle group located on one side in a predetermined direction and the predetermined nozzle A background image nozzle group having a second nozzle group located on the other side of the direction;
A controller that forms an image by forming a dot by ejecting a fluid from the nozzle to each pixel defined on the medium,
Forming dots by ejecting fluid from the main image nozzle group to the pixels belonging to the first region forming the main image on the medium,
Dots formed by ejecting fluid from the first nozzle group onto the pixels belonging to a second region that forms an image by a fluid that forms the background image on the medium and that does not form the main image. , And a control unit that forms dots formed by ejecting fluid from the second nozzle group,
A fluid ejecting apparatus comprising: The fluid ejection device according to claim 1,
When forming the main image and the background image on the medium,
In order to form a background image portion that is the background image of the first region and overlaps the main image, one of the first nozzle group and the second nozzle group is added to the pixel belonging to the first region. Ejecting fluid from the group to form dots,
Fluid ejection device. The fluid ejecting apparatus according to claim 1 or 2,
The first nozzle row in which the nozzles that eject the fluid forming the main image are arranged in the predetermined direction, the first nozzle row having the main image nozzle group;
The nozzles that eject the fluid forming the background image are second nozzle rows that are arranged in the predetermined direction, and are arranged with the first nozzle rows in a moving direction that is a direction that intersects the predetermined direction, and the first nozzles A second nozzle row having a group and the second nozzle group;
Have
A dot forming operation in which fluid is ejected from the nozzles while relatively moving the first nozzle row, the second nozzle row, and the medium in the movement direction; and the first nozzle row and the second nozzle row
An image is formed by repeating the transport operation of transporting the relative position of the medium to the nozzle row to the other side of the predetermined direction,
The dot forming operation for ejecting fluid from the first nozzle group to form dots on the pixels belonging to the second region, and ejecting fluid from the second nozzle group to the pixels belonging to the second region The dot forming operation for forming dots is different,
Fluid ejection device. The fluid ejection device according to claim 3,
When forming the main image and the background image on the medium,
In the first mode in which the background image is formed before the main image with respect to a predetermined area of the medium, the main image is the nozzle of the first nozzle row aligned with the second nozzle group in the moving direction. The main image is formed by a nozzle group, and the first image is formed by the first nozzle group.
Forming the background image of the region,
In the second mode in which the main image is formed prior to the background image with respect to a predetermined region of the medium, the main image is the nozzle of the first nozzle row aligned with the first nozzle group in the moving direction. The main image is formed by a nozzle group, and the first image is formed by the second nozzle group.
Forming the background image of the region;
Fluid ejection device. The fluid ejection device according to claim 4,
In the first mode, a background image of the second region is formed by the first nozzle group, the second nozzle group, and the main image nozzle group,
In the second mode, a background image of the second region is formed by the nozzles of the first nozzle group, the second nozzle group, and the first nozzle row aligned with the second nozzle group in the movement direction. To
Fluid ejection device. The fluid ejection device according to any one of claims 3 to 5,
Fluid is ejected from one of the first nozzle group and the second nozzle group to the pixels forming the background image and surrounding the pixels belonging to the first region. Let
Fluid ejection device. A main image nozzle group that is a predetermined number of nozzles for ejecting a fluid that forms a main image on a medium, and a number of nozzles that is greater than the predetermined number that ejects a fluid that forms a background image of the main image on the medium. A fluid ejecting apparatus comprising a background image nozzle group, which is a background image nozzle group including a first nozzle group located on one side in a predetermined direction and a second nozzle group located on the other side in the predetermined direction. A fluid ejecting method for ejecting fluid from the nozzle to each pixel defined above,
Forming a dot by ejecting fluid from the main image nozzle group to the pixels belonging to the first region forming the main image on the medium;
Dots formed by ejecting fluid from the first nozzle group onto the pixels belonging to a second region that forms an image by a fluid that forms the background image on the medium and that does not form the main image. And forming dots formed by ejecting fluid from the second nozzle group,
A fluid ejection method comprising:

Images