JP6745364B2 - Image forming apparatus, control apparatus, control method, and control program - Google Patents

Description

The present invention relates to an image forming apparatus, a control device, a control method, and a control program.

Conventionally, as an ink for forming an image on a recording medium, an image forming apparatus for forming an image using a fluorescent ink and a non-fluorescent ink is known. As such an image forming apparatus, according to Japanese Patent Application Laid-Open No. 2004-242242, the color of the fluorescent ink can be appropriately expressed by first ejecting the fluorescent ink and then ejecting the non-fluorescent ink. An image forming apparatus is described.

JP, 2004-291511, A

However, in the technique described in Patent Document 1, it is described that the fluorescent ink is ejected first and then the non-fluorescent ink is ejected, and how to control the ink ejection order. There was not enough consideration as to what to do. Therefore, there is a concern that the color developability of the image formed using the fluorescent ink may not be sufficiently improved.

The present disclosure has been made in view of the above circumstances, and is capable of improving the color developability of an image formed using fluorescent ink, an image forming apparatus, a control device, a control method, and a control program. The purpose is to provide.

In order to achieve the above object, an image forming apparatus according to an embodiment of the present disclosure includes a recording head in which ejection ports for ejecting ink toward a recording medium are arranged in a first direction for each of a plurality of types of ink including a fluorescent ink, A first moving unit that relatively moves at least one of the recording head and the recording medium in a first direction, and a second moving unit that relatively moves at least one of the recording head and the recording medium in a second direction intersecting the first direction. a moving unit, on the basis of the information about the fluorescence of multiple types of ink, and a control unit for controlling the amount of ink ejected per path for a plurality types of ink each control unit, the information Based on this, control of the droplet ejection order of a plurality of types of ink is further performed.

Further, when the fluorescent ink and the non-fluorescent ink are overlapped on the recording medium and droplets are ejected, the control unit of the image forming apparatus of the present disclosure causes the fluorescent ink to be ejected on the recording medium based on the information. The control may be performed in such a manner that the order is higher than other inks.

Further, the image forming apparatus of the present disclosure ejects ink on a recording medium by ejecting ink a plurality of times in a first direction and a plurality of times in a second direction for each area of a predetermined size by a plurality of predetermined passes. When forming the, the control unit may perform control to increase the amount of fluorescent ink in the first half of the plurality of passes more than the amount of non-fluorescent ink.

Further, the image forming apparatus of the present disclosure ejects ink on a recording medium by ejecting ink a plurality of times in a first direction and a plurality of times in a second direction for each area of a predetermined size by a plurality of predetermined passes. When forming the, the control unit may perform control such that the amount of fluorescent ink in the first half of the plurality of passes is larger than the amount of fluorescent ink in the latter half of the passes.

Further, the image forming apparatus of the present disclosure ejects ink on a recording medium by ejecting ink a plurality of times in a first direction and a plurality of times in a second direction for each area of a predetermined size by a plurality of predetermined passes. When forming the, the control unit may perform control to increase the amount of the non-fluorescent ink in the latter half of the plurality of passes more than the amount of the fluorescent ink.

Further, the control unit of the image forming apparatus according to the present disclosure may control the ink ejection order by changing the position of the nozzle that ejects the ink for each type of ink.

In addition, the control unit of the image forming apparatus of the present disclosure ejects the non-fluorescent ink, the pretreatment liquid, the pretreatment liquid, and the fluorescent ink. You may control to drop.

Further, the control device of the present disclosure is configured such that a recording head in which ejection ports for ejecting ink toward a recording medium are arranged in the first direction for each of a plurality of types of ink, and at least one of the recording head and the recording medium is in the first direction. An image forming apparatus including a first moving unit that relatively moves and a second moving unit that relatively moves at least one of a recording head and a recording medium in a second direction intersecting the first direction is controlled. The control device includes a control unit that controls the amount of ink ejected for each pass for each of the plurality of types of ink, based on information about the fluorescence of the plurality of types of ink , and the control unit Based on this, control of the droplet ejection order of a plurality of types of ink is further performed.

Further, according to the control method of the present disclosure, a recording head in which ejection openings for ejecting ink toward a recording medium are arranged in the first direction for each of a plurality of types of ink, and at least one of the recording head and the recording medium is arranged in the first direction. A method of controlling an image forming apparatus, comprising: a first moving unit that relatively moves, and a second moving unit that relatively moves at least one of a recording head and a recording medium in a second direction intersecting the first direction. That is, based on the information on the fluorescence of a plurality of types of ink, a process of controlling the amount of ink ejected for each pass for each of a plurality of types of ink, and based on the information, And a process of controlling the droplet ejection order .

Further, the control program of the present disclosure includes a recording head in which ejection ports for ejecting ink toward a recording medium are arranged in the first direction for each of a plurality of types of ink, and at least one of the recording head and the recording medium is in the first direction. A method of controlling an image forming apparatus, comprising: a first moving unit that relatively moves, and a second moving unit that relatively moves at least one of a recording head and a recording medium in a second direction intersecting the first direction. That is, based on the information on the fluorescence of a plurality of types of ink, a process of controlling the amount of ink ejected for each pass for each of a plurality of types of ink, and based on the information, And a process of controlling the droplet ejection order .

According to the present disclosure, it is possible to improve the color developability of an image formed using a fluorescent ink.

FIG. 3 is an external perspective view showing an example of the configuration of the image forming apparatus of the first embodiment. FIG. 3 is a schematic diagram schematically showing a recording medium conveyance path of the image forming apparatus of the first embodiment. FIG. 3 is a plan perspective view showing an example of an arrangement form of recording heads arranged on the carriage of the first embodiment. FIG. 4 is an enlarged view of the recording head in FIG. 3. FIG. 6 is an explanatory diagram illustrating an example of a multi-pass image forming method in the image forming apparatus of the first embodiment. FIG. 3 is a schematic diagram schematically showing the relationship between the number of each scan (pass) and the position of the droplet ejection formed by the scan (pass) in the drawing operation in which the eight passes are set as one unit in the first embodiment. is there. It is a block diagram showing an example of a configuration of an image forming apparatus of the first embodiment. FIG. 4 is an explanatory diagram illustrating a relationship between an ink droplet ejection order and an ink arrangement on a recording medium. 6 is a flowchart showing an example of the flow of an ink amount control process executed by the ejection control unit of the first embodiment. 6 is a graph showing an example of ink amounts for each pass of fluorescent ink and non-fluorescent ink in the first embodiment. 6 is a graph showing another example of the ink amount for each pass of the fluorescent ink and the non-fluorescent ink in the first embodiment. 11 is a flowchart showing an example of the flow of an ink amount control process executed by the ejection control unit of the present embodiment of the second embodiment. 8 is a graph showing an example of ink amounts for each pass of fluorescent ink and non-fluorescent ink in the second embodiment. FIG. 4 is an explanatory diagram illustrating a relationship between an ink droplet ejection order and an ink arrangement on a recording medium. FIG. 11 is a plan perspective view showing an example of an arrangement form of recording heads arranged on the carriage of the third embodiment. 11 is a flowchart showing an example of the flow of an ink amount control process executed by the ejection control unit of the third embodiment. It is an enlarged view of a recording head in a fourth embodiment. FIG. 9 is a schematic diagram schematically showing the relationship between the number of each scan (pass) by the drawing operation in which the eight passes are set as one unit and the position of the droplet ejection formed by the scan (pass) in the fourth embodiment. is there.

Embodiments for carrying out the present invention will be described in detail below with reference to the drawings.

[First Embodiment]
First, the configuration of the image forming apparatus 10 according to the present exemplary embodiment will be described with reference to FIG. FIG. 1 is an external perspective view showing the configuration of an example of the image forming apparatus 10 of this embodiment. The image forming apparatus 10 of the present embodiment is an image forming apparatus that forms an image on the recording medium 12 using a plurality of types of ink including fluorescent ink (hereinafter, referred to as “fluorescent ink”). As shown in FIG. 1, it is a so-called wide format printer.

The image forming apparatus 10 includes an apparatus body 20 and support legs 22 that support the apparatus body 20. The apparatus body 20 includes a recording head 24, a platen 26, a guide mechanism 28, and a carriage 30.

The recording head 24 of the present embodiment is a drop-on-demand type inkjet head that ejects ink toward the recording medium 12.

The medium used as the recording medium 12 in the present embodiment is not particularly limited, and examples thereof include paper, cloth, non-woven fabric, and synthetic chemical fiber. In the present embodiment, an permeable medium is used as the recording medium 12. There is.

The platen 26 supports the recording medium 12. The guide mechanism 28 and the carriage 30 movably support the recording head 24. The guide mechanism 28 is arranged above the platen 26 in a direction that intersects the conveyance direction of the recording medium 12 (hereinafter, simply referred to as “conveyance direction”) and is parallel to the medium supporting surface of the platen 26. Has been done. The upper side of the platen 26 means a higher position above the platen 26 with the gravity direction being “lower”. In the present embodiment, a direction that intersects the transport direction and is parallel to the recording surface of the recording medium 12 corresponds to the “main scanning direction”, and the transport direction corresponds to the “sub scanning direction”. In FIG. 1, the arrow X indicates the sub scanning direction, and the arrow Y direction indicates the main scanning direction.

The main scanning direction of the present embodiment corresponds to an example of the “first direction” of the present disclosure, and the sub-scanning direction of the present embodiment corresponds to an example of the “second direction” of the present disclosure.

The carriage 30 is supported along the guide mechanism 28 so as to be capable of reciprocating in the main scanning direction.

A recording head 24 is mounted on the carriage 30 (see also FIG. 3). The recording head 24 moves integrally with the carriage 30 along the guide mechanism 28. In the image forming apparatus 10 of the present embodiment, the recording head 24 is moved relative to the recording medium 12 in the main scanning direction by reciprocating the carriage 30 in the main scanning direction along the guide mechanism 28.

The apparatus body 20 is provided with a mounting portion 38 for mounting the ink cartridge 36. The ink cartridge 36 is a replaceable ink tank that stores ink. The ink cartridge 36 is provided corresponding to each color of ink used in the image forming apparatus 10. The image forming apparatus 10 of the present embodiment forms an image using four color inks of cyan (C), magenta (M), yellow (Y), and black (K) as an example. Any one (one) of the four color inks has fluorescence. Hereinafter, as a specific example, a case where the magenta (M) ink has fluorescence will be described.

Each ink cartridge 36 for each color is connected to the recording head 24 by an ink supply path (not shown) formed independently. The ink cartridge 36 is replaced when the remaining amount of ink of each color is low.

Next, the conveyance path of the recording medium 12 in the image forming apparatus 10 of this embodiment will be described. FIG. 2 is a schematic diagram schematically showing an example of the transport path of the recording medium 12 of the image forming apparatus 10 according to the present exemplary embodiment. As shown in FIG. 2, the upper surface of the platen 26 serves as a support surface that supports the recording medium 12. A roller 40 is provided on the upstream side in the transport direction with respect to the position of the platen 26.

The recording medium 12 of the present embodiment is supplied as a sheet-shaped medium that is rolled. The recording medium 12 delivered from the supply-side roll 42 is conveyed by the roller 40. An image is formed by ejecting ink from the recording head 24 onto the recording medium 12 that has reached a position facing the recording head 24. A winding roll 44 that winds up the recording medium 12 on which an image has been formed is provided downstream of the position of the recording head 24 in the transport direction. Further, a guide 46 is provided in the conveyance path of the recording medium 12 between the platen 26 and the winding roll 44.

The conveyance method in the image forming apparatus 10 is not particularly limited, but in the present embodiment, as an example, the recording medium 12 sent from the supply-side roll 42 is wound around the take-up roll 44 via the platen 26. A roll-to-roll system is adopted. As another method, for example, a method in which the winding roll 44 is omitted may be used. Further, the image forming apparatus 10 may include a cutting device such as a cutter that cuts the recording medium 12 into a desired size. Further, the supply of the recording medium 12 is not limited to the case of supplying the recording medium 12 in a roll state, and for example, a medium such as a cut sheet (so-called sheet) may be supplied separately.

In the image forming apparatus 10 according to the present exemplary embodiment, the temperature adjusting unit 50, the pre-temperature adjusting unit 52, and the pre-temperature adjusting unit 52 are provided on the back surface side of the platen 26, that is, on the opposite side of the medium supporting surface of the platen 26 that supports the recording medium 12. An after-temperature control unit 54 is provided. The temperature adjustment unit 50 adjusts the temperature of the recording medium 12 during image formation. In the image forming apparatus 10 of the present exemplary embodiment, the temperature adjustment by the temperature adjustment unit 50 allows the viscosity of the ink that has landed on the recording medium 12 and the physical properties such as the surface tension to have desired values, so that a desired dot diameter can be obtained. Is possible. The pre-temperature control unit 52 is provided on the upstream side in the transport direction of the temperature control unit 50. The after-temperature control unit 54 is provided on the downstream side of the temperature control unit 50 in the transport direction. The configuration of the image forming apparatus 10 according to the present exemplary embodiment is not limited, and at least one of the pre-temperature adjusting unit 52 and the after-temperature adjusting unit 54 may be omitted.

Next, the carriage 30 in the image forming apparatus 10 according to the present exemplary embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a plan perspective view showing an example of the arrangement of the recording heads 24 arranged on the carriage 30 of this embodiment. Further, FIG. 4 is an enlarged view of the recording head 24 in FIG.

As shown in FIGS. 3 and 4, the recording head 24 has nozzles for ejecting ink for each color ink of cyan (C), magenta (M), yellow (Y), and black (K). Nozzle rows 61C, 61M, 61Y, and 61K in which 62 (see FIG. 4) are arranged in the sub-scanning direction are provided. In the following description, when the nozzle arrays 61C, 61M, 61Y, and 61K are collectively referred to without distinguishing each, the description of the symbols (C, M, Y, and K) representing the colors that distinguish each is omitted. However, it is simply referred to as the “nozzle row 61”.

In FIG. 3, the nozzle row 61 is shown by a dotted line, and the individual illustration of the nozzles 62 is omitted. As an example, in the recording head 24 shown in FIGS. 3 and 4, from the left of the drawing, each nozzle row is arranged in the order of a yellow nozzle row 61Y, a magenta nozzle row 61M, a cyan nozzle row 61C, and a black nozzle row 61K. However, the type of ink, the combination of colors, and the number of inks are not limited to the present embodiment. In the present embodiment, the “ink type” is not limited to a color type, but includes a type corresponding to the ink property.

For example, in addition to the four colors of CMYK, light ink such as light cyan or light magenta may be used, or instead of or in combination with the light ink, another color such as white (white) color may be used. Special color inks may also be used. The recording head 24 is provided with a nozzle row 61 that ejects the corresponding ink according to the type of ink color used. Further, the arrangement order of the nozzle rows 61 for each color is not particularly limited.

As in the example shown in FIGS. 3 and 4, the recording head 24 of the present embodiment has head modules (24C, 24M, 24Y, and 24K) configured for each of the nozzle arrays 61C, 61M, 61Y, and 61K. , Are arranged side by side in the main scanning direction. Specifically, the recording head 24 of this embodiment has a head module 24Y having a nozzle row 61Y for ejecting yellow ink, a head module 24M having a nozzle row 61M for ejecting magenta ink, and a cyan ink. A head module 24C having a nozzle row 61C for ejecting black ink and a head module 24K having a nozzle row 61K for ejecting black ink are arranged side by side at equal intervals along the main scanning direction. Hereinafter, the head modules 24C, 24M, 24Y, and 24K may be referred to as recording heads 24C, 24M, 24Y, and 24K.

As shown in FIG. 4, in each of the nozzle arrays 61C, 61M, 61Y, and 61K, a plurality of nozzles 62 are arranged side by side at regular intervals in the sub-scanning direction. FIG. 4 shows, as an example, a configuration in which 30 nozzles 62 are arranged in each of the nozzle rows 61C, 61M, 61Y, and 61K. Nozzle numbers 0 to 29 are given to each nozzle 62 for each color.

The nozzle numbers of the present embodiment are sequentially assigned to each nozzle 62 from the one end side to the other end side of the nozzle row 61 in the sub-scanning direction by a continuous number. In this embodiment, the nozzle number starts from 0, but the first nozzle number may be 1, and any integer may be used. The nozzle number can be used as an identification number indicating the position of each nozzle 62.

Further, in the present embodiment, as an example, the nozzle row 61 in which 30 nozzles 62 are arranged in a row along the sub-scanning direction is shown, but the number of nozzles 62 included in the nozzle row 61 and the arrangement of the nozzles 62 are shown. The form is not limited to this embodiment. For example, the nozzle row 61 may be a nozzle row 61 in which the nozzles 62 are arranged at equal intervals in the sub-scanning direction by a two-dimensional nozzle array in which a plurality of nozzle rows 61 are combined.

In the image forming apparatus 10 of the present embodiment, as an example, as the ink ejection method of the recording head 24, a piezo jet method in which ink is ejected by deformation of a piezoelectric element is adopted. As the ejection energy generating element, an electrostatic actuator may be used instead of the piezoelectric element. Also, a thermal jet method may be used in which a heating element (heating element) such as a heater is used to heat ink to generate bubbles, and the pressure causes the ink droplets to fly.

The recording head 24 ejects ink onto the recording medium 12 while moving in the main scanning direction, and forms an image on an area of the recording medium 12 having a certain length in the sub scanning direction. Then, when the recording medium 12 is moved by a certain amount in the sub-scanning direction after the image is formed, the recording head 24 forms an image in the next area. In the image forming apparatus 10 of the present embodiment, the image formation is repeated every time the recording medium 12 is moved by a certain amount in the sub-scanning direction, and the image formation is performed over the entire recording area of the recording medium 12.

As described above, the recording head 24 of the present embodiment is a serial type recording head. The image forming apparatus 10 (see FIG. 1) of the present embodiment employs a multi-pass method that realizes a predetermined printing resolution by a plurality of main scans of the print head 24 in the main scan direction.

Next, an image forming method by the multi-pass method in the image forming apparatus 10 of this embodiment will be described.

FIG. 5 is an explanatory diagram illustrating an example of a multi-pass image forming method. Here, in order to simplify the description, a case where the configuration of the recording head 24 is simplified, the nozzle row 61 of the recording head 24 is one row, and an image is formed by the one nozzle row 61 will be described as an example. It can be understood that the nozzle row 61 is a representative of any one of the nozzle rows 61C, 61M, 61Y, and 61K described in FIG.

Further, in the present embodiment, the recording medium 12 is intermittently conveyed in the sub-scanning direction, but for convenience of illustration, FIG. 5 illustrates a state in which the recording head 24 is intermittently moved in the sub-scanning direction instead of the recording medium 12. Showing. In FIG. 5, the recording medium 12 is omitted and only the movement of the recording head 24 is shown.

As shown in FIG. 5, ink is ejected from the nozzles 62 while the recording head 24 is moving in the main scanning direction (left and right direction in FIG. 5). A two-dimensional image is formed on the recording medium 12 by the combination of the reciprocating movement of the recording head 24 along the main scanning direction and the intermittent conveyance of the recording medium 12 in the sub-scanning direction (the vertical direction in FIG. 5). ..

In the present embodiment, it is also referred to as “scan” or “scan” that the recording head 24 ejects ink from the nozzles 62 to form dots while moving from end to end in the main scanning direction of the recording medium 12. Say. In the present embodiment, when scanning is performed, the movement of the recording head 24 from one end to the other in the main scanning direction of the recording medium 12 is referred to as “pass”, and the number of movements is represented as “pass”. In the image forming apparatus 10 of the present embodiment, the recording head 24 scans in both the forward pass and the backward pass in the main scanning direction. That is, in this embodiment, when the recording head 24 reciprocates in the main scanning direction, it is counted as “two passes”.

In the image forming apparatus 10 of the present embodiment, as an example, an image having a desired resolution is formed by N (N is a natural number) scans (passes). In this case, the relative positional relationship (here, the positional relationship in the sub-scanning direction) between the recording medium 12 and the recording head 24 in the (N+1)th scan is as shown in FIG. That is, in order to form an image with a desired resolution by scanning N times, the recording medium 12 is intermittently conveyed in the sub-scanning direction, such as the first time, the second time, the third time,... And just at the (N+1)th time. The positional relationship is such that it is connected to a position corresponding to the length of the nozzle row 61 (hereinafter referred to as "nozzle row length"). In order to seamlessly connect the operation of N times of writing, the (N+1)th scan is performed by moving in the subscanning direction from the position of the first scan in the subscanning direction by “nozzle row length+1 nozzle pitch”. The “nozzle row length” is the length in the sub-scanning direction of the nozzle row 61 in which the nozzles 62 are arranged side by side in the sub-scanning direction, and corresponds to the inter-nozzle distance of the nozzles 62 located at both ends of the nozzle row 61. .. The “nozzle pitch” is the nozzle interval in the sub scanning direction in the nozzle row 61.

As an example, using the recording head 24 having the nozzle row 61 in which the nozzles 62 are arranged at a nozzle array density of 100 npi, two passes in the main scanning direction and four passes in the sub-scanning direction (main 2×sub 4) 8 passes (8 A case will be described in which the resolution of 600 dpi in the main scan×400 dpi in the sub-scan is realized by (writing). In this case, the number of nozzles to be used is 24, which is a multiple of 8 and which is the closest value to the number of nozzles (30) or less. npi (nozzle per inch) is a unit representing the number of nozzles 62 per inch. dpi (dot per inch) is a unit representing the number of dots per inch. One inch is about 25.4 mm.

In the following, the interval of the droplet ejection points determined from the resolution is referred to as the “droplet ejection point interval”, and the grid representing the positions of the droplet ejection points that can be formed is referred to as the “droplet ejection point grid”. The “droplet ejection point” is synonymous with the “pixel”. The “droplet ejection point interval” is synonymous with the “pixel interval” and corresponds to the minimum dot interval in resolution. The “droplet spot grid” is synonymous with the “pixel grid”. "Lattice" is synonymous with a cell of a matrix represented by rows and columns.

When the resolution is 600 dpi in the main scanning×400 dpi in the sub-scanning, the droplet ejection point spacing in the main scanning direction is 25.4 mm/600≈42.3 μm, and the droplet ejection point spacing in the sub-scanning direction is 25.4 mm/400=63. It is 5 μm. This represents the size “42.3 μm×63.5 μm” of one cell (corresponding to one pixel) of the droplet ejection point grid. Regarding the control of the conveyance of the recording medium 12 and the control of the droplet ejection position (that is, the droplet ejection timing) from the recording head 24, the conveyance amount and the position are controlled in units of the droplet ejection point interval determined from this resolution. In addition, the droplet ejection point interval determined from the resolution may be referred to as a “pixel pitch”. Further, the nozzle pitch can be expressed in the unit of length, but instead of this, it can be expressed in the unit of the droplet ejection point interval (pixel pitch) in the sub-scanning direction. For example, when the nozzle array density is 100 npi with respect to the resolution of 400 dpi in the sub-scanning direction, the nozzle pitch is four times the pixel pitch in the sub-scanning direction. Can be expressed as “4”.

When N=8 by 2 passes in the main scanning direction and 4 passes in the sub-scanning direction, 2×4 droplet ejection point grids are scanned by 8 times of scanning (8 passes) and scanning lines in the main scanning direction are scanned by 2 times ( And a scan line in the sub-scanning direction are formed by four scans (passes).

FIG. 6 shows the relationship between the number (1 to 8) of each scan (pass) by the drawing operation in which such a scan (pass) is performed as one unit and the position of the droplet ejection formed by the scan (pass). It is the schematic diagram which showed an example of typically. In FIG. 6, each cell numbered 1 to 8 represents the position of the droplet ejection formed by the nozzle 62 (the position of the pixel), and the number 1 to 8 indicates that the position of the pixel is the number of times. Represents the number of the scan (pass) that is formed in the scan (pass). For example, the cells (pixels) to which the number “1” is attached represent the positions of droplets formed in the first scan (pass).

As is clear from FIG. 6, in the arrangement distribution of the numbers 1 to 8, the grid of “2×4” in the main scanning direction 2×the sub scanning direction 4 is the basic unit of repetition. In this embodiment, this 2×4 lattice is referred to as a “basic unit lattice”. It goes without saying that the method of filling the basic unit lattice (droplet ejection order) is not limited to the example shown in FIG. The basic unit cell of the present embodiment corresponds to an example of the “region of a predetermined size” in the present disclosure.

In the image forming apparatus 10 of the present embodiment, for example, the resolution and the scanning pattern are determined according to the image forming mode based on the image quality, the image forming speed, etc., and the number of cells of the basic unit grid, the cell array form, and the scanning of each cell are performed. Number (scanning order) is determined.

Next, the configuration of the control system of the image forming apparatus 10 of this embodiment will be described. FIG. 7 is a block diagram showing an example of the configuration of the control system of the image forming apparatus 10. As shown in FIG. 7, the image forming apparatus 10 includes a control device 102. Examples of the control device 102 include a microcomputer including a CPU (Central Processing Unit) and the like. The control device 102 controls the entire image forming apparatus 10 by executing various programs read from the information storage unit 124.

The control device 102 includes a recording medium conveyance control unit 104, a carriage drive control unit 106, an image processing unit 110, and an ejection control unit 112. Each of these units is realized by hardware, software, or a combination thereof.

The recording medium conveyance control unit 104 controls the conveyance driving unit 114 for conveying the recording medium 12 (see FIG. 1). The transport drive unit 114 includes a drive motor that drives the roller 40 (see FIG. 2) and a drive circuit thereof. The recording medium 12 conveyed on the platen 26 (see FIG. 1) is intermittently conveyed in the sub-scanning direction in swath width units in accordance with the reciprocal scanning (movement of the printing pass) in the main scanning direction by the recording head 24. .. The swath width is a length in the sub-scanning direction that is determined by a scan repeating cycle due to the reciprocating movement of the carriage 30, and the nozzle row length, which is the length of the nozzle row 61 in the sub-scanning direction, is defined as the number of scan repetitions. It is calculated by dividing by the number of passes. The number of passes, which is the number of scan repetitions, is the number of scans required to complete drawing with the set resolution.

The carriage drive control unit 106 controls the main scanning drive unit 116 that moves the carriage 30 in the main scanning direction. The main scanning drive unit 116 includes a drive motor connected to the moving mechanism of the carriage 30 and a control circuit thereof.

The transport driving unit 114 of the present embodiment corresponds to an example of the “second moving unit” of the present disclosure, and the main scanning driving unit 116 of the present embodiment corresponds to an example of the “first moving unit” of the present disclosure. ..

An encoder 130 is attached to the drive motor of the main scanning drive unit 116 and the drive motor of the transport drive unit 114. A pulse signal corresponding to the rotation amount and the rotation speed of each drive motor is input to the control device 102 from the encoder 130. The control device 102 grasps the position of the carriage 30 and the position of the recording medium 12 based on the pulse signal input from the encoder 130.

The image processing unit 110 performs image processing on image data input from an external device via an image input I/F (InterFace) 126, and converts the image data into dot data for image formation.

The image processing unit 110 performs halftone processing by the dither method. That is, the image processing unit 110 performs a pixel value quantization process on a continuous tone image that is input image data using a dither mask, and generates a halftone image corresponding to dot data for image formation. To do.

The ejection control unit 112 controls the ejection of ink from each nozzle 62 of the recording head 24 by controlling the head drive circuit 128 that drives the recording head 24 based on the dot data generated by the image processing unit 110. To do. Further, the ejection control unit 112 of the present embodiment controls the amount of ink ejected for each pass for each of the plurality of types of ink, based on the information regarding the fluorescence of the plurality of types of ink. The ejection control unit 112 of the present embodiment corresponds to an example of the “control unit” of the present disclosure.

The information storage unit 124 uses, for example, a non-volatile memory, and stores various programs and various data necessary for controlling the control device 102. For example, the information storage unit 124 stores, as programs, a control program executed by each unit of the control device 102, a scanning pattern program, and the like. The scanning pattern program is a program for image formation of the above-described multi-pass system, and reciprocal scanning (pass movement) in the main scanning direction of the recording head 24 with respect to the recording medium 12 intermittently conveyed in the sub scanning direction and the number of passes ( Specify the number of scan repetitions). The movement of the pass accompanied by the movement of the recording head 24 in the main scanning direction includes at least one of the movement direction of the recording head 24 in dot formation, the selection of the nozzle 62 for ejecting ink, and the ejection timing. A scanning pattern that is determined by the movement of the path and the combination of the number of paths is called a "scanning pattern".

An input device 122 and a display device 120 are connected to the control device 102. As the input device 122, various means such as a keyboard, a mouse, a touch panel, or an operation button can be adopted, and an appropriate combination thereof may be used. A user (an operator or the like) of the image forming apparatus 10 can input various information using the input device 122.

A liquid crystal display or the like is used as the display device 120. The user can confirm the information input by the input device 122, various other information, the system state, and the like through the display on the display device 120.

The sensor 132 is attached to the carriage 30. The control device 102 can grasp the width of the recording medium 12 based on the sensor signal input from the sensor 132.

As described above, in the image forming apparatus 10 of the present embodiment, an image is formed on the recording medium 12 using fluorescent ink (magenta (M) as a specific example). In forming an image, the ejection control unit 112 controls the amount of ink ejected for each pass for each of the plurality of types of ink, based on the information regarding the fluorescence of the plurality of types of ink.

As the above-mentioned control, the ejection control unit 112 of the present embodiment controls the fluorescent ink so that the fluorescent ink is higher than the other inks on the recording medium 12. This control will be described below.

First, the order of the inks on the recording medium 12 when a plurality of types of inks are ejected onto the recording medium 12, which is a permeable medium, will be described with reference to FIG. In FIG. 8, as an example, a magenta ink 90M (hereinafter referred to as “magenta ink 90M”) is ejected onto the recording surface 12A of the recording medium 12 and then a cyan ink 90C (hereinafter referred to as “cyan ink”). 90C”) is deposited in a stacked manner.

First, as shown in FIG. 8A, when the magenta ink 90M is ejected, as shown in FIG. 8B, the magenta ink 90M that has landed on the recording medium 12 has the surface side of the recording surface 12A ( The upper side of FIG. 8) is permeated. In this state, as shown in FIG. 8B, the cyan ink 90C is ejected onto the recording surface 12A of the recording medium 12. Then, as shown in FIG. 8C, the cyan ink 90C landed on the recording medium 12 permeates to the lower layer side of the magenta ink 90M. As a result, as shown in FIG. 8B, the magenta ink 90M that has landed on the recording medium 12 first has a larger recording surface 12A than the cyan ink 90C that has landed on the recording medium 12 later. In the cyan ink 90C that has penetrated to the lower layer side of the magenta ink 90M, the light incident from the recording surface 12A side is blocked by the magenta ink 90M. On the other hand, the light incident from the recording surface 12A reaches the magenta ink 90M without being blocked. Therefore, as described above, the fluorescent magenta ink 90M can sufficiently exhibit the fluorescent characteristics, and, for example, the saturation is improved.

Thus, when the permeable medium is used as the recording medium 12, the ink that has landed first on the recording medium 12 tends to be on the upper side (on the recording surface 12A side) of the recording medium 12 than the ink that has landed later. is there.

Therefore, the ejection control unit 112 of the image forming apparatus 10 according to the present exemplary embodiment controls the fluorescent ink so that the fluorescent ink is higher than the other inks on the recording medium 12 (positioned on the recording surface 12 side). In the first half of the plurality of passes for generating the basic lattice, the amount of fluorescent ink (total amount of ejected ink, hereinafter referred to as “ink amount”) is calculated as non-fluorescent ink (hereinafter referred to as “non-fluorescent ink”). Control) (hereinafter referred to as “ink amount control”).

By performing the control in this manner, the fluorescent ink and the non-fluorescent ink have a larger amount of droplets (landing) of the fluorescent ink earlier on the recording medium 12. Therefore, the ratio of the fluorescent ink on the recording medium 12 (on the recording surface 12A side) is higher than that of the non-fluorescent ink.

FIG. 9 is a flowchart showing an example of the flow of the ink amount control process executed by the ejection control unit 112 of this embodiment. In the present embodiment, when the image forming apparatus 10 executes image formation instructed by the input device 122 or the like, the ejection control unit 112 executes the control program stored in the information storage unit 124, The ink amount control process shown in FIG. 9 is executed.

In step S100, the ejection control unit 112 determines whether the image forming apparatus 10 includes fluorescent ink. Here, the method by which the ejection control unit 112 determines whether or not the image forming apparatus 10 includes fluorescent ink is not particularly limited. For example, when the ink cartridge 36 is attached to the image forming apparatus 10, information indicating the fluorescence of the ink supplied by the ink cartridge 36 is stored in the information storage unit 124 or the like, and the ejection control unit 112 is stored. A method of making a determination based on information may be used. Further, for example, when the user gives an instruction to form an image from the ejection control unit 112 or the like, the presence or absence of fluorescent ink or the like is also input as information indicating the fluorescence of the ink, and the ejection control unit 112 is based on the input information. Alternatively, a method of making a determination may be used.

When the image forming apparatus 10 does not include the fluorescent ink, it may include the magenta ink which is a non-fluorescent ink, for example. In this way, when the image forming apparatus 10 does not include the fluorescent ink, the determination in step S100 becomes a negative determination, and the present ink amount control processing ends. In this case, the ejection control unit 112 does not control the ink amount for each pass by the main ink amount control processing, but performs control in normal image formation, that is, control to eject a predetermined ink amount according to image data. ..

On the other hand, in the present embodiment, as described above, since the magenta ink 90M is the fluorescent ink among the four color inks (four inks) included in the image forming apparatus 10, the determination in step S100 becomes a positive determination and the step S102. Move to.

In step S102, the ejection control unit 112 determines whether or not fluorescent ink is used for image formation. For example, when forming a monochrome image, the magenta ink 90M may not be used for forming the image. When the fluorescent ink is not used for forming an image in this way, the determination in step S102 becomes negative, and the present ink amount control processing ends. In this case, similarly to the case where the negative determination is made in step S100, the ejection control unit 112 performs control in normal image formation.

On the other hand, when fluorescent ink is used for image formation, the determination in step S102 becomes affirmative, and the process proceeds to step S104.

In step S104, the ejection control unit 112 controls the ink amount for each pass according to the movement of the carriage 30 (recording head 24) by the main scanning drive unit 116.

The ejection control unit 112 of the present embodiment sets the amount of fluorescent ink in the first half of the plurality of passes for generating the basic unit grid to be greater than the amount of non-fluorescent ink, and in the latter half of the passes. The amount of fluorescent ink is controlled to be smaller than the amount of non-fluorescent ink. In this embodiment, the total amount of ink used to generate the basic unit grid is the same as the amount of ink in normal image formation for each ink.

FIG. 10 shows, as an example, the relationship between the amount of magenta ink 90M, which is a fluorescent ink, and the amount of cyan ink 90C, which is a non-fluorescent ink, when a basic unit grid is generated by eight scans (8 passes). Indicates.

In the example shown in FIG. 10, the ink amount of the magenta ink 90M, which is the fluorescent ink, decreases as the number of scans (pass number) increases. On the other hand, the ink amount of the cyan ink 90C, which is a non-fluorescent ink, increases as the number of scans (pass number) increases. In the example illustrated in FIG. 10, in the first-half pass (bus numbers 1 to 4), the amount of magenta ink 90M that is fluorescent ink is larger than the amount of cyan ink 90C that is non-fluorescent ink. In the latter half of the passes (pass numbers 5 to 8), the amount of the non-fluorescent ink, the cyan ink 90C, is larger than that of the fluorescent ink, the magenta ink 90M.

In response to the scanning of the carriage 30 by the main scanning drive unit 116, the ejection control unit 112 sets eight scans (eight passes) as one unit based on the basic unit grid, as shown in FIG. Control the amount of ink.

In the next step S106, the ejection control unit 112 determines whether or not to end the present ink amount control processing. For example, when image formation is to be ended, the determination in step S106 is affirmative, and the present ink amount control processing is ended. On the other hand, if the image formation is in progress, the determination in step S106 becomes negative, the process returns to step S104, and the ink amount control is performed until the image formation is completed.

As described above, in the image forming apparatus 10 of the present embodiment, the ejection control unit 112 determines the amount of ink ejected for each pass for each of a plurality of types of ink based on the information regarding the fluorescence of the plurality of types of ink. As a control, in the first half of the plurality of passes, the amount of the magenta ink 90M that is the fluorescent ink is made to be larger than the amount of the cyan ink 90C that is the non-fluorescent ink.

In other words, from another viewpoint, the ejection control unit 112 of the present embodiment sets the amount of the magenta ink 90M, which is the fluorescent ink in the first half of the plurality of passes, to be larger than the amount of the ink in the latter half of the passes. It is in control. In other words, from another viewpoint, the ejection control unit 112 according to the present embodiment sets the amount of the cyan ink 90C, which is the non-fluorescent ink, in the latter half of the plurality of passes, as compared with the amount of the magenta ink 90M, which is the fluorescent ink. Is also controlled to increase.

By performing such control, the ejection control unit 112 of the present embodiment performs control such that the fluorescent ink is placed on top of the other inks on the recording medium. As a result, according to the image forming apparatus 10 of the present embodiment, it is possible to improve the color developability of the image formed using the fluorescent ink.

In the present embodiment, when performing eight scans (passes), which is a unit for generating the basic lattice, the amount of the magenta ink 90M, which is the fluorescent ink, is gradually decreased according to the pass, while The form in which the amount of the cyan ink 90C that is the fluorescent ink is gradually increased has been described, but the control method is not limited to this.

For example, as shown in FIG. 11, the ejection control unit 112 may control. In the example shown in FIG. 11, the ejection control unit 112 sets the same amount of ink of the first half pass numbers 1 to 4 of the magenta ink 90M, which is the fluorescent ink, to the same amount of ink of the second half pass numbers 5 to 8. The same amount of ink in one pass is controlled to be larger in the first half pass than in the second half pass. The cyan ink 90C, which is a non-fluorescent ink, has the same amount of ink in the first half of pass numbers 1 to 4, the same amount of ink in the latter half of pass numbers 5 to 8, and the ink in one pass. The amount is controlled so that the number of passes in the latter half is larger than that of the passes in the first half. Furthermore, the ejection control unit 112 sets the amount of the magenta ink 90M, which is the fluorescent ink, in the first half pass to be larger than the amount of the cyan ink 90C, which is the non-fluorescent ink, and the non-fluorescent ink in the latter half pass. The control is performed such that the amount of the cyan ink 90C, which is the above, is larger than the amount of the magenta ink 90M, which is the fluorescent ink.

[Second Embodiment]
In the image forming apparatus 10 of the present embodiment, the ink is a control for the ejection control unit 112 to set the fluorescent ink on the recording medium 12 so as to be higher than the other inks (positioned on the recording surface 12 side). The amount control process is different from the ink amount control process of the first embodiment (see FIG. 9).

As in the example shown in FIGS. 3 and 4 described above, the recording heads 24 (nozzle rows 61) for the respective colors are arranged in the sub-scanning direction (Y direction). Therefore, in one reciprocating pass (two passes), the order of ink landed on the recording medium 12 is reversed between the forward pass and the return pass.

Therefore, the ejection control unit 112 of the image forming apparatus 10 according to the present embodiment ejects (landes) the fluorescent ink after the non-fluorescent ink on a path where the fluorescent ink is deposited (landed) before the non-fluorescent ink. The control is performed so that the amount of ink is larger than that of the pass). By performing the control in this manner, the fluorescent ink and the non-fluorescent ink have a larger amount of droplets (landing) of the fluorescent ink earlier on the recording medium 12. Therefore, the ratio of the fluorescent ink on the recording medium 12 (on the recording surface 12A side) is higher than that of the non-fluorescent ink.

FIG. 12 is a flowchart showing an example of the flow of ink amount control processing executed by the ejection control unit 112 of this embodiment. Since the ink amount control process of the present embodiment shown in FIG. 12 is different in that step S105 is executed instead of step S104 of the ink amount control process (see FIG. 9) in the first embodiment, step S105 will be described. To do.

In step S<b>105, the ejection control unit 112 ejects the fluorescent ink (landing on the recording medium 12) before the non-fluorescent ink according to the movement of the carriage 30 (recording head 24) by the main scanning drive unit 116. In the pass, the amount of ink is controlled to be larger than that in the pass in which droplets are deposited (landed on the recording medium 12) after the non-fluorescent ink. Further, in the present embodiment, the ejection control unit 112 controls the non-fluorescent ink so that the amount of ink is constant regardless of the pass order (number).

FIG. 13 shows, as an example, the relationship between the amount of magenta ink 90M, which is a fluorescent ink, and the amount of cyan ink 90C, which is a non-fluorescent ink, when a basic unit grid is generated by eight scans (8 passes). Indicates.

In the example shown in FIG. 13, when the pass number is odd (1, 3, 5, 7), the fluorescent ink ejects droplets (lands on the recording medium 12) before the non-fluorescent ink, and the pass number is even. (2, 4, 6, 8) shows the case where the fluorescent ink ejects (landes) after the non-fluorescent ink.

In the example shown in FIG. 13, in the case of the magenta ink 90M, which is a fluorescent ink, the case of ejecting (landing) the droplet before the non-fluorescent ink is larger than the case of depositing (landing) after the non-fluorescent ink. A large amount of ink. In addition, in the example shown in FIG. 13, in the pass (bus numbers 1, 3, 5, and 7) in which the fluorescent ink is ejected (landed) first, the magenta ink 90M, which is the fluorescent ink, has a smaller ink amount. The amount is larger than the amount of the cyan ink 90C that is a non-fluorescent ink.

Note that, also in the present embodiment, the total amount of ink used to generate the basic unit grid is the same as the amount of ink in normal image formation for each ink.

As described above, the ejection control unit 112 according to the present embodiment shows eight scans (eight passes) as one unit based on the basic unit grid in response to the scan of the carriage 30 by the main scan drive unit 116, and is shown in FIG. As described above, the ink amount of each ink is controlled.

By the control performed by the ejection control unit 112 in this way, the ratio of the fluorescent ink to the upper side (recording surface 12A side) on the recording medium 12 becomes higher than that of the non-fluorescent ink.

Therefore, also in the image forming apparatus 10 of the present embodiment, it is possible to improve the color developability of the image formed using the fluorescent ink, as in the image forming apparatus 10 of the first embodiment.

In the present embodiment, the case has been described in which the amount of the cyan ink 90C that is the non-fluorescent ink is controlled to be a constant amount regardless of the pass, but the amount of the non-fluorescent ink is not limited to this. For example, the amount of ink may be different between when the non-fluorescent ink is ejected (landed) before the fluorescent ink and when it is subsequently ejected (landed). In this case, for example, control may be performed such that the amount of ink when the non-fluorescent ink is ejected (landed) earlier than the fluorescent ink is larger than when the droplet is ejected (landed) later.

[Third Embodiment]
In the image forming apparatus 10 according to the first and second embodiments, the ejection control unit 112 determines that the ink that has landed on the recording medium 12 first appears on the recording medium 12 (recording surface 12A). The amount of ink is controlled for each pass based on the information about the fluorescence of each of the plurality of inks. On the other hand, in the image forming apparatus 10 according to the present embodiment, the ejection control unit 112 performs control so that the ink that has previously landed on the recording medium 12 is on the recording medium 12 (recording surface 12A). .. In the present embodiment, the YMCK inks are collectively referred to as “color ink” regardless of whether they are fluorescent or non-fluorescent.

As described above, when the ink penetrates into the recording medium 12, the ink that has landed on the recording medium 12 first is on the recording medium 12 (recording surface 12A). On the other hand, for example, if the ink does not penetrate into the recording medium 12, the ink that has landed first will overlap with the ink that has landed first.

This phenomenon will be described with reference to FIG. Note that, in FIG. 14, as an example, a case is shown in which the cyan ink 90C that is a non-fluorescent ink is ejected onto the recording surface 12A of the recording medium 12 and the magenta ink 90M that is a fluorescent ink is overlapped and ejected. ..

First, as shown in FIG. 14(A), when the pretreatment liquid 90B is dropped, the pretreatment liquid 90B landed on the recording medium 12 is discharged onto the recording surface 12A as shown in FIG. 14(B). The recording surface 12A of the recording medium 12 is hardened or semi-hardened.

In this state, when the cyan ink 90C is ejected as shown in FIG. 14B, the cyan ink 90C landed on the recording medium 12 does not permeate the recording surface 12A as shown in FIG. It is located above the medium 12A. Furthermore, in this state, when the magenta ink 90M is ejected as shown in FIG. 14C, the magenta ink 90M is positioned on the cyan ink 90C as shown in FIG. 14D.

As a result, as shown in FIG. 14D, the magenta ink 90M that has landed on the recording medium 12 later on the recording surface 12A of the recording medium 12 is better than the cyan ink 90C that has landed on the recording medium 12 first. By being located on the upper side, the fluorescent magenta ink 90M can sufficiently exhibit the fluorescent characteristics, and, for example, the saturation is improved.

Therefore, in the image forming apparatus 10 of the present embodiment, the pretreatment liquid that cures (including semi-curing) the surface of the recording medium 12 is ejected onto the recording surface 12A of the recording medium 12, and the cured recording surface 12A is ejected onto the recording surface 12A. Control for ejecting color ink including fluorescent ink is performed.

For example, in the image forming apparatus 10 of the present embodiment, as in the example shown in FIG. 15, the carriage 30 ejects the pretreatment liquid with the recording head 24B1 including the nozzle row 61B1 for ejecting the pretreatment liquid. And a recording head 24B2 including a nozzle row 61B2 for performing the above. As shown in FIG. 14, the recording head 24B1 and the recording head 24B2 are respectively located at both ends in the sub-scanning direction where the recording heads 24 (head modules 24Y, 24M, 24C, and 24K) of other colors are arranged. doing. By arranging the recording heads 24B1 and 24B2 in this way, the pretreatment liquid is first deposited (landed) on the recording medium 12 in both the forward pass and the backward pass.

FIG. 16 is a flowchart showing an example of the flow of ink amount control processing executed by the ejection control unit 112 of this embodiment. Since the ink amount control process of the present embodiment shown in FIG. 16 is different in that step S200 is executed instead of step S104 of the ink amount control process (see FIG. 9) in the first embodiment, step S200 will be described. To do.

In step S200, the ejection control unit 112 controls the head drive circuit 128 to first eject the pre-vision treatment liquid from the recording head 24B1 or the recording head 24B2, and then, depending on the image data, another color ink ( (Magenta ink 90M, yellow ink 90Y, cyan ink 90C, etc.) is ejected.

As described above, in the image forming apparatus 10 of the present embodiment, regardless of which color ink is the fluorescent ink or the non-fluorescent ink, the pretreatment liquid is ejected before the color ink is ejected. As a result, the surface of the recording medium 12 is made impermeable. Therefore, in the image forming apparatus 10 of the present embodiment, when the fluorescent ink is ejected after the non-fluorescent ink is ejected, it is possible to improve the color developability of the image formed using the fluorescent ink.

In the present embodiment, as described above, regardless of which color ink is the fluorescent ink or the non-fluorescent ink, the pretreatment liquid is ejected before the color ink is ejected. However, the order of droplet ejection of the pretreatment liquid is not limited to this embodiment. For example, when the non-fluorescent ink is ejected (landed) first, the ejection control unit 112 subsequently applies the pretreatment liquid to the non-fluorescent ink before the fluorescent ink is deposited. The droplets may be controlled to be ejected. Further, for example, when the fluorescent ink is ejected before the non-fluorescent ink, the pretreatment liquid may not be ejected. In this case, as in the first and second embodiments, the fluorescent ink ejected first by penetrating the recording medium 12 becomes higher than the non-fluorescent ink.

[Fourth Embodiment]
In the image forming apparatus 10 of the first and second embodiments, the ejection control unit 112 controls the ink amount for each pass based on the information regarding the fluorescence of each of the plurality of inks, so that the fluorescent ink is changed to the non-fluorescent ink. The recording medium 12 is controlled to be on the upper side (recording surface 12A side). On the other hand, in the image forming apparatus 10 according to the present exemplary embodiment, the ejection control unit 112 causes the ink ejection control unit 112 to eject the ink according to the arrangement of the nozzles 62 that eject (eject) ink of each color determined by whether the ink is fluorescent or non-fluorescent. A case of controlling the droplet ejection order of will be described.

In the image forming apparatus 10 of the present embodiment, the arrangement of the recording heads 24 of each color on the carriage 30 is different from that of the recording heads 24 of the first embodiment (see FIGS. 3 and 4).

In the present embodiment, as an example, the magenta ink 90M that is a fluorescent ink, and the yellow ink 90Y and the cyan ink C that are non-fluorescent inks will be described. FIG. 17 shows an example of an enlarged view of the recording heads 24M, 24Y, and 24C of this embodiment.

In the arrangement of the recording heads 24 of the present embodiment, the positions of the nozzles 62 are displaced in the sub-scanning direction for each color by the resolution (in the present embodiment, 400 dpi as described above in the first embodiment).

Also in the image forming apparatus 10 of the present embodiment, the image forming method by the multi-pass method is the same as that of the image forming apparatus 10 of the first embodiment (see FIG. 5).

In FIG. 18, the numbers (1 to 8) of each scan (pass) by the drawing operation in which the image forming apparatus 10 of the present embodiment uses eight scans (pass) as one unit, and the scan (pass) forms The schematic diagram which showed typically an example of the relationship of the position of the ejected droplet is shown.

The basic unit grid 96M generated by the magenta ink 90M, the basic unit grid 96Y generated by the yellow ink 90Y, and the basic unit grid 96C generated by the cyan ink 96C shown in FIG. It is formed at the same location. That is, the basic unit grid 96M, the basic unit grid 96Y, and the basic unit grid 96C overlap each other on the recording medium 12.

As shown in FIG. 18, the basic unit grid 96M of the magenta ink 90M is similar to the basic unit grid (see FIG. 6) described in the first embodiment. On the other hand, since the nozzles of the basic unit grid 96Y of the yellow ink 90Y and the basic unit grid 96C of the cyan ink 90C are displaced from each other according to the layout of the recording head 24 as shown in FIG. The position of the formed droplets (the position of the pixel) is different from that of the basic unit lattice described in the first embodiment. Therefore, for example, in the example shown in FIG. 18, the pass number 1 of the magenta ink 90M, the pass number 2 of the cyan ink 90C, and the pass number 3 of the cyan ink 90C correspond to the same position. This indicates that at this position, the yellow ink 90Y is deposited (landed) on the magenta ink 90M, and the cyan ink 90C is deposited (landed) on it. Therefore, at this position of the recording medium 12, the magenta ink 90M is located at the highest position on the recording surface 12A of the recording medium 12.

As described above, in the example shown in FIG. 18, the yellow ink 90Y is ejected after the magenta ink 90M in pass numbers 2 to 8. Further, the cyan ink 90C is ejected after the magenta ink 90M in pass numbers 3 to 8.

Therefore, in the example shown in FIG. 18, the magenta ink 90M is located above the yellow ink 90Y and the cyan ink 90C on the recording surface 12A of the recording medium 12 at pass numbers 3 to 8.

Therefore, also in the image forming apparatus 10 of the present embodiment, it is possible to improve the color developability of an image formed using the magenta ink 90M that is a fluorescent ink, as in the image forming apparatus 10 of the first embodiment. As described above, when the magenta ink 90M is the fluorescent ink and the yellow ink 90Y and the cyan ink 90C are the non-fluorescent inks, among the colors of the image formed on the recording medium 12, R (red) and B( Blue) The color becomes more saturated.

On the other hand, unlike the above, even when the yellow ink 90Y is a fluorescent ink and the magenta ink 90M and the cyan ink 90C are non-fluorescent inks, at least the yellow ink 90Y is ejected before the cyan ink 90C, thereby recording. Since it is on the top of the medium 12, it is possible to similarly improve the color developability of an image formed using the yellow ink 90Y. In this case, among the colors of the image formed on the recording medium 12, the saturation of G (green) color is high.

In the present embodiment, as an example, the recording heads 24M, 24Y, and 24C for the magenta ink 90M, which is a fluorescent ink, and the yellow ink 90Y and a cyan ink C, which are non-fluorescent inks, are as shown in FIG. In the above, the case where the arrangement is displaced in the sub-scanning direction according to the resolution has been described, but the present invention is not limited to this embodiment.

For example, when each recording head 24 is movable in the sub-scanning direction, the ejection control unit 112 arranges the recording heads 24 (nozzles 62) based on the information regarding the fluorescence of the ink of each color and the resolution. It may be shifted in the sub-scanning direction as illustrated in FIG.

Furthermore, for example, when the position (order) in which each recording head 24 is arranged in the main scanning direction can be changed, the ejection control unit 112 exemplifies FIG. 17 based on the information regarding the fluorescence of the ink of each color. As described above, the arrangement (order) of the fluorescent ink recording heads 24 may be controlled.

In any case, the ejection control unit 112 determines that the order (arrangement) of the pass numbers of the basic unit lattices generated by the fluorescent ink is the same as the order (arrangement) of the pass numbers of the basic unit lattice 96M illustrated in FIG. It may be controlled so that

As described above, in the image forming apparatus 10 of each of the above-described embodiments, the nozzles 62, which are the ejection openings for ejecting ink toward the recording medium 12, are arranged in the main scanning direction for each of a plurality of types of ink including fluorescent ink. The recording head 24, a main scanning drive unit that relatively moves at least one of the recording head 24 and the recording medium 12 in the main scanning direction, and a sub-scanning unit that crosses at least one of the recording head 24 and the recording medium 12 in the main scanning direction. An ejection control unit 112 that controls the amount of ink ejected for each pass for each of the plurality of types of ink, based on the transport drive unit that relatively moves in the scanning direction and information regarding the fluorescence of the plurality of types of ink. And

As a result, according to the image forming apparatus 10 of each of the above-described embodiments, the fluorescent ink is on the recording medium in an order higher than the other inks.

Therefore, according to the image forming apparatus 10 of each of the above-described embodiments, it is possible to improve the color developability of the image formed using the fluorescent ink.

The configuration of the image forming apparatus 10 and the operation of the ejection control unit 112 described in each of the above embodiments are examples, and it goes without saying that they can be changed according to circumstances without departing from the spirit of the present invention. Nor. For example, it goes without saying that the above embodiments may be combined. Further, for example, in each of the above-described embodiments, the case where the carriage drive control unit 106 moves the carriage 30 (recording head 24) in the main scanning direction by the main scanning drive unit 116 has been described, but the carriage 30 is fixed and the recording medium is fixed. 12 may be moved in the main scanning direction. Similarly, in each of the above embodiments, the case where the recording medium conveyance control unit 104 conveys the recording medium 12 in the sub-scanning direction by the conveyance driving unit has been described, but the recording medium 12 is fixed and the carriage 30 (the recording head 24). ) May be moved in the sub-scanning direction.

10 image forming apparatus 12 recording medium 12A recording surface 20 apparatus body 22 support legs 24, 24B1, 24B2 recording heads 24Y, 24M, 24C, 24K head module 26 platen 28 guide mechanism 30 carriage 36 ink cartridge 38 mounting portion 40 roller 42 roll 44 Take-up roll 46 Guide 50 Temperature controller 52 Pre temperature controller 54 After temperature controller 61, 61Y, 61M, 61C, 61K, 61B1, 61B2 Nozzle row 62 Nozzle 90C Cyan ink 90M Magenta ink 90Y Yellow ink 90B Pretreatment liquid 96C , 96M, 96Y Basic unit grid 102 Control device 104 Recording medium transport control unit 106 Carriage drive control unit 110 Image processing unit 112 Ejection control unit 114 Transport drive unit 116 Main scanning drive unit 120 Display device 122 Input device 124 Information storage unit 126 image Input I/F
128 head drive circuit 130 encoder 132 sensor X, Y arrow

Claims (10)

A recording head in which ejection openings for ejecting ink toward a recording medium are arranged in a first direction for each of a plurality of types of ink including fluorescent ink,
A first moving unit that relatively moves at least one of the recording head and the recording medium in the first direction;
A second moving unit that relatively moves at least one of the recording head and the recording medium in a second direction intersecting the first direction;
A control unit that controls the amount of ink ejected for each pass for each of the plurality of types of ink, based on information about the fluorescence of the plurality of types of ink,
Equipped with
The image forming apparatus , wherein the control unit further controls the droplet ejection order of the plurality of types of ink based on the information . The control unit, based on the information, when the fluorescent ink and the non-fluorescent ink are overlapped and ejected onto the recording medium, the fluorescent ink is more likely than the other inks on the recording medium. Control to make the order also above,
The image forming apparatus according to claim 1 . When an image is formed on the recording medium by ejecting ink a plurality of times in the first direction and a plurality of times in the second direction for each area having a predetermined size by a plurality of predetermined passes,
The control unit performs control to increase the amount of fluorescent ink in the first half of the plurality of passes to be greater than the amount of non-fluorescent ink,
The image forming apparatus according to claim 1 . When an image is formed on the recording medium by ejecting ink a plurality of times in the first direction and a plurality of times in the second direction for each area having a predetermined size by a plurality of predetermined passes,
The control unit controls the amount of the fluorescent ink in the first half of the plurality of passes to be larger than the amount of the fluorescent ink in the latter half of the passes.
The image forming apparatus according to claim 1 . When an image is formed on the recording medium by ejecting ink a plurality of times in the first direction and a plurality of times in the second direction for each area having a predetermined size by a plurality of predetermined passes,
The control unit performs control to increase the amount of non-fluorescent ink in the latter half of the plurality of passes above the amount of fluorescent ink.
The image forming apparatus according to claim 1 . The control unit controls the ink droplet ejection order by changing the position of the nozzle that ejects the ink for each type of ink.
The image forming apparatus according to any one of claims 1 to 5. The control unit controls the droplet ejection of the non-fluorescent ink, the droplet ejection of the pretreatment liquid, the droplet ejection of the pretreatment liquid, and the ejection of the fluorescent ink.
The image forming apparatus according to any one of claims 1 to 6. A recording head in which ejection openings for ejecting ink toward a recording medium are arranged in the first direction for each of a plurality of types of ink; and at least one of the recording head and the recording medium is relatively moved in the first direction. A control device for controlling an image forming apparatus, comprising: a first moving unit; and a second moving unit that relatively moves at least one of the recording head and the recording medium in a second direction intersecting the first direction. There
A control unit that controls the amount of ink ejected for each pass for each of the plurality of types of ink, based on information about the fluorescence of the plurality of types of ink ,
The said control part is a control apparatus which further controls the droplet ejection order of the said multiple types of ink based on the said information . A recording head in which ejection openings for ejecting ink toward a recording medium are arranged in the first direction for each of a plurality of types of ink; and at least one of the recording head and the recording medium is relatively moved in the first direction. A method of controlling an image forming apparatus, comprising: a first moving unit; and a second moving unit that relatively moves at least one of the recording head and the recording medium in a second direction intersecting the first direction. ,
A process of controlling the amount of ink ejected for each pass for each of the plurality of types of ink, based on information about the fluorescence of the plurality of types of ink;
A process of controlling the droplet ejection order of the plurality of types of ink based on the information,
Control method including. A recording head in which ejection openings for ejecting ink toward a recording medium are arranged in the first direction for each of a plurality of types of ink; and at least one of the recording head and the recording medium is relatively moved in the first direction. Controlling an image forming apparatus including one moving unit and a second moving unit that relatively moves at least one of the recording head and the recording medium in a second direction intersecting with the first direction is executed by a computer. A control program for
A process of controlling the amount of ink ejected for each pass for each of the plurality of types of ink, based on information about the fluorescence of the plurality of types of ink;
A process of controlling the droplet ejection order of the plurality of types of ink based on the information,
Control program including.