JP2017094673A - Liquid injection device and liquid injection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance reactivity between pretreatment liquid and ink and to improve printing image quality irrespective of a type of a medium.SOLUTION: A liquid injection device 10 comprises: a transportation mechanism 32 transporting a medium 22 in a first direction; a pretreatment liquid coating mechanism coating a medium 22 with pretreatment liquid 40; a liquid injection section including ink nozzle arrays LI1 through LI4 injecting ink 41; and a control section 30 controlling the pretreatment liquid coating mechanism and the liquid injection section. The liquid injection device has dryness degree adjustment sections Ht adjusting a dryness degree of the pretreatment liquid 40 with which the medium 22 is coated among the ink nozzle arrays LI1 through LI4 and the pretreatment liquid coating mechanism.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a technique for ejecting a liquid such as ink onto a medium.

  In an ink jet type liquid ejecting apparatus, a pretreatment liquid containing a reaction component such as an aggregating agent and a solvent component such as water and an ink containing a pigment in order to improve the fixability of the ink to the medium and improve the printing image quality Has been developed in which a liquid is ejected by a liquid ejecting head, a pretreatment liquid is landed on the medium, and then ink is landed to cause both to react on the surface of the medium. For example, in the inkjet head disclosed in Patent Document 1, since the nozzle row for ejecting the pretreatment liquid (reaction liquid) is provided upstream of the nozzle row for ejecting ink in the medium conveyance direction, After the pretreatment liquid is landed on the ink, the ink can be landed.

JP 2013-256136 A

  However, when the ink is landed after the pretreatment liquid is landed first with the ink jet head having the configuration of Patent Document 1, the degree of drying of the pretreatment liquid varies depending on the type of the medium. It may not be possible. For example, in a medium with low absorbability, the pretreatment liquid is difficult to permeate, so the solvent component such as water of the pretreatment liquid remaining on the surface is difficult to dry. There is also a fear. On the other hand, in a medium with high absorbency, the pretreatment liquid easily penetrates, so that the pretreatment liquid that has landed first penetrates the medium and the residual amount of the reaction component on the medium surface decreases, so that it is easily dried and spreads wet. It becomes difficult. In this case, the amount of reaction with the ink that has landed later decreases, and the print image quality is likely to deteriorate. In view of the above circumstances, an object of the present invention is to increase the reactivity between a pretreatment liquid and ink and improve the print image quality regardless of the type of medium.

  In order to solve the above problems, a liquid ejecting apparatus of the present invention includes a transport mechanism that transports a medium in a first direction, a pretreatment liquid coating mechanism that coats the pretreatment liquid onto the medium, and an ink nozzle that ejects ink. A liquid ejecting section including a row, a pretreatment liquid coating mechanism, and a control section for controlling the liquid ejection section, and the pretreatment liquid coated on the medium between the ink nozzle row and the pretreatment liquid coating mechanism A drying degree adjusting unit that adjusts the degree of drying. According to the above configuration, since the drying degree adjusting unit that adjusts the degree of drying of the pretreatment liquid that has landed on the medium is provided between the ink nozzle row and the pretreatment liquid coating mechanism, the pretreatment liquid coating is performed on the medium. The degree of drying of the pretreatment liquid can be adjusted by the drying degree adjusting unit after the pretreatment liquid is coated by the mechanism and before the ink lands on the medium from the ink nozzle row. In this way, by configuring the liquid jet head so that the degree of drying of the pretreatment liquid can be adjusted, the degree of drying of the pretreatment liquid can be adjusted according to the type of medium. Therefore, regardless of the type of medium, the reactivity between the pretreatment liquid and the ink can be increased, and the printing image quality can be improved.

  In a preferred aspect of the present invention, the drying degree adjustment unit includes a determination unit that includes a drying mechanism that promotes drying of the pretreatment liquid and determines the type of the medium, and the control unit is determined by the determination unit. Whether the drying of the pretreatment liquid is promoted by the drying mechanism is selected according to the type of the medium. According to the above aspect, the degree of drying of the pretreatment liquid can be adjusted by selecting whether or not the drying mechanism promotes drying of the pretreatment liquid according to the type of medium determined by the determination unit. Therefore, regardless of the type of medium, the reactivity between the pretreatment liquid and the ink can be increased, and the printing image quality can be improved.

  In a preferred aspect of the present invention, the drying degree adjustment unit includes an adjustment nozzle row that ejects the pretreatment liquid, and includes a determination unit that determines the type of the medium, and the control unit is determined by the determination unit. Depending on the type of medium, either the pretreatment liquid coating mechanism or the adjustment nozzle row is selected to cover the medium with the pretreatment liquid. According to the above aspect, the degree of drying of the pretreatment liquid can be adjusted by selecting either the pretreatment liquid coating mechanism or the adjustment nozzle row in accordance with the type of medium determined by the determination unit. Therefore, regardless of the type of medium, the reactivity between the pretreatment liquid and the ink can be increased, and the printing image quality can be improved.

  In a preferred aspect of the present invention, the drying degree adjustment unit includes an adjustment region having a width for adjusting the distance between the pretreatment liquid coating mechanism and the ink nozzle row, and a determination unit that determines the type of the medium; The control unit selects the width of the adjustment area according to the type of medium determined by the determination unit. According to the above aspect, the width of the adjustment region is selected according to the type of medium determined by the determination unit, and the distance between the pretreatment liquid coating mechanism and the ink nozzle row is adjusted. Since the drying time of the treatment liquid can be adjusted, the degree of drying of the pretreatment liquid can be adjusted. Therefore, regardless of the type of medium, the reactivity between the pretreatment liquid and the ink can be increased, and the printing image quality can be improved.

  In a preferred aspect of the present invention, a liquid ejecting head including a pretreatment liquid coating mechanism and a liquid ejecting unit, and a moving mechanism for reciprocating the liquid ejecting head in a second direction intersecting the first direction are provided. The treatment liquid coating mechanism and the ink nozzle row are each arranged along the first direction, and the drying degree adjustment unit extends in a strip shape in the first direction, and the pretreatment liquid coating mechanism, the drying degree adjustment unit, and the ink The nozzle row has an overlapping portion in a side view from the second direction. According to the above aspect, the ink can be landed while the liquid jet head is reciprocated in the second direction and the medium is covered with the pretreatment liquid and the degree of drying is adjusted. Further, according to this aspect, the pretreatment liquid coating mechanism and the drying degree adjusting unit have a portion that overlaps with the ink nozzle row in the side view from the second direction, so that they do not overlap in the side view in the second direction. Compared to the case, the liquid ejecting head can be downsized in the first direction which is the conveyance direction of the medium.

  In a preferred aspect of the present invention, the pretreatment liquid coating mechanism and the drying degree adjusting unit are arranged on one side or both sides in the second direction of the ink nozzle row. According to the above aspect, the ink can be landed while the pretreatment liquid is covered on the medium and the degree of drying is adjusted by either or both of the forward movement and the backward movement of the liquid ejecting head.

  In a preferred aspect of the present invention, a post-treatment liquid coating mechanism that coats a post-treatment liquid on a medium on which ink has landed is provided. In the side view from the second direction, the post-treatment liquid coating mechanism is a side surface from the second direction. It has a portion that overlaps the ink nozzle in view. According to the above aspect, since the post-treatment liquid can also be ejected after ink landing, the gloss and light resistance can be improved while improving the image quality of the printed image. In addition, since the post-processing liquid coating mechanism overlaps the ink nozzle row in a side view from the second direction, the liquid ejecting head may not be enlarged in the first direction even if the post-processing liquid coating mechanism is arranged. it can.

  In a preferred aspect of the present invention, the pretreatment liquid coating mechanism overlaps the ink nozzle row in a side view from the second direction on the upstream side in the first direction than the posttreatment liquid coating mechanism. According to the above configuration, on the upstream side of the liquid ejecting head, the ink is landed while the pretreatment liquid is coated on the medium and the degree of drying of the medium is adjusted, and the ink is also applied to the medium on the downstream side of the liquid ejecting head. After the image is landed, the post-treatment liquid can be coated.

  In a preferred aspect of the present invention, the liquid ejecting head includes a pretreatment liquid coating mechanism and a liquid ejecting unit, and the liquid ejecting head is a line head that is long in a second direction intersecting the first direction, Each of the pretreatment liquid coating mechanism and the ink nozzle row is arranged along the second direction, the drying degree adjusting unit extends in a band shape in the second direction, and the pretreatment liquid coating mechanism is viewed from the ink nozzle row. The pretreatment liquid coating mechanism is disposed on the upstream side in the first direction, and has a portion that overlaps with the nozzles of the ink nozzle row in a side view from the first direction. According to the above aspect, even if the liquid ejecting head is a line head, the degree of drying of the pretreatment liquid can be adjusted according to the type of medium. Therefore, regardless of the type of medium, the reactivity between the pretreatment liquid and the ink can be increased, and the printing image quality can be improved.

  In a preferred aspect of the present invention, the liquid ejecting head includes a post-processing liquid coating mechanism that ejects the post-processing liquid onto the medium on which the ink has landed, and the post-processing liquid coating mechanism is in the first direction when viewed from the ink nozzle row. The post-processing liquid coating mechanism is disposed on the downstream side and has a portion overlapping the ink nozzle row in a side view from the first direction. According to the above aspect, the degree of drying of the pretreatment liquid can be adjusted according to the type of medium, and the medium can be coated with the posttreatment liquid after ink landing. Accordingly, it is possible to improve the gloss and light resistance while improving the image quality of the printed image.

A liquid ejecting method according to a preferred aspect of the present invention is a liquid ejecting method for a liquid ejecting apparatus in which a medium is coated with a pretreatment liquid and then ink is landed on the medium.
The liquid ejecting apparatus includes a transport mechanism that transports the medium in the first direction, a pretreatment liquid coating mechanism that coats the pretreatment liquid onto the medium, and a liquid ejecting unit that includes an ink nozzle row that ejects ink. Between the ink nozzle row and the pretreatment liquid coating mechanism, there is a drying degree adjustment unit that adjusts the degree of drying of the pretreatment liquid coated on the medium, and the drying degree adjustment unit promotes drying of the pretreatment liquid. It is configured including a drying mechanism, and the type of the medium is determined, and whether or not to accelerate the drying of the pretreatment liquid by the drying mechanism is selected according to the determined type of the medium. According to the above configuration, the degree of drying of the pretreatment liquid can be adjusted by selecting whether or not to accelerate the drying of the pretreatment liquid by the drying mechanism according to the determined medium type. Therefore, regardless of the type of medium, the reactivity between the pretreatment liquid and the ink can be increased, and the printing image quality can be improved.

  A liquid ejecting method according to a preferred aspect of the present invention is a liquid ejecting method of a liquid ejecting apparatus in which a medium is coated with a pretreatment liquid and then ink is landed on the medium. A transport mechanism that transports in a first direction; a pretreatment liquid coating mechanism that coats a pretreatment liquid onto a medium; and a liquid ejecting unit that includes an ink nozzle array that ejects ink. Between the coating mechanism, there is a drying degree adjustment unit that adjusts the degree of drying of the pretreatment liquid coated on the medium, and the drying degree adjustment unit includes a drying mechanism that promotes drying of the pretreatment liquid. The medium type is discriminated, and according to the discriminated medium type, either the pretreatment liquid coating mechanism or the adjustment nozzle row is selected to coat the medium with the pretreatment liquid. According to the above configuration, the degree of drying of the pretreatment liquid can be adjusted by selecting either the pretreatment liquid coating mechanism or the adjustment nozzle row in accordance with the determined medium type. Therefore, regardless of the type of medium, the reactivity between the pretreatment liquid and the ink can be increased, and the printing image quality can be improved.

1 is a configuration diagram of a liquid ejecting apparatus according to a first embodiment. FIG. 6 is a plan view of an ejection surface of the liquid ejection head. FIG. 3 is a cross-sectional view of a liquid ejecting head. It is a figure for demonstrating the state of the pre-processing liquid when the landing time difference of a pre-processing liquid and an ink is changed with respect to a different type medium. In FIG. 4, it is a figure for demonstrating the state of the ink after ink landing. 3 is a flowchart illustrating control of the liquid jet head according to the first embodiment. FIG. 6 is a plan view of an ejection surface of a liquid ejection head according to a first modification example of the first embodiment. FIG. 10 is a plan view of an ejection surface of a liquid ejection head according to a second modification example of the first embodiment. FIG. 9 is a plan view of an ejection surface of a liquid ejection head according to a third modification example of the first embodiment. FIG. 10 is a plan view of an ejection surface of a liquid ejection head according to a fourth modification example of the first embodiment. FIG. 9 is a plan view of an ejection surface of a liquid ejection head according to a second embodiment. 10 is a flowchart illustrating control of a liquid jet head according to a second embodiment. FIG. 9 is a plan view of an ejection surface of a liquid ejection head according to a third embodiment. 10 is a flowchart illustrating control of a liquid jet head according to a third embodiment. FIG. 10 is a configuration diagram of a liquid ejecting apparatus according to a fourth embodiment. FIG. 10 is a configuration diagram of a liquid ejecting apparatus according to a modification of the fourth embodiment.

<First Embodiment>
FIG. 1 is a configuration diagram of a liquid ejecting apparatus 10 according to the first embodiment of the present invention. The liquid ejecting apparatus 10 is a printing apparatus (inkjet apparatus) that prints an image on the surface of the medium 22 by ejecting ink 41 that is an example of a liquid onto the medium 22. The medium 22 is a recording medium such as a printing paper or a film to be ejected with the ink 41. Details of the type of medium used in the first embodiment will be described later.

  The liquid ejecting apparatus 10 is equipped with a liquid container 24 that stores liquid, and the liquid container 24 stores pretreatment liquid 40 and ink 41. The ink 41 is a liquid (color ink) containing a color material such as a pigment or a dye. For example, a total of four inks 41 of cyan (C), magenta (M), yellow (Y), and black (K) are stored in the liquid container 24. Note that a resin material may be included in the ink 41.

  The pretreatment liquid 40 is a liquid (optimizer ink) for improving the fixability of the ink 41 that lands on the surface of the medium 22, for example, a reaction component such as an aggregating agent that reacts with the ink 41, moisture, or a solvent. And other solvent components. Color materials and resin materials contained in the ink 41 are not contained in the pretreatment liquid 40. The pretreatment liquid 40 may contain a surfactant. In FIG. 1, the liquid container 24 is illustrated as one element for the sake of convenience, but a configuration in which the pretreatment liquid 40 and a plurality of types of ink 41 are stored in separate liquid containers 24 or a plurality of types of ink 41 are used. For each of these, a configuration stored in a separate liquid container 24 may be employed.

  The liquid ejecting apparatus 10 includes a control unit 30, a transport mechanism 32, a moving mechanism 34, and a liquid ejecting head 36. The control unit 30 is, for example, a control unit such as a CPU (Central Processing Unit) or an FPGA (Field Programmable Gate Array), a ROM (Read Only Memory) 301, a RAM (Random Access Memory) 302, and a determination unit that determines the type of the medium 22. 303. The ROM 301 is a rewritable flash ROM, for example. The ROM 301 stores a program executed by the control unit 30 and various data (such as a medium data table described later) necessary for executing the program. The RAM 302 stores data temporarily used when the control unit 30 executes the program. A management device (not shown) such as a personal computer is connected to the control unit 30. The control unit 30 comprehensively controls each element of the liquid ejecting apparatus 10 according to an instruction from the management apparatus. The determination unit 303 determines the type of the medium 22 based on the medium data table. Details of the type determination of the medium 22 will be described later.

  The transport mechanism 32 transports the medium 22 in the Y direction (example of the first direction) under the control of the control unit 30. The transport mechanism 32 of the first embodiment includes a supply roller 322 and a discharge roller 324. The supply roller 322 is installed on the upstream side (negative side in the Y direction) of the discharge roller 324 and conveys the medium 22 to the discharge roller 324 side. The discharge roller 324 downstream of the medium 22 supplied from the supply roller 322 Transport to (positive side in Y direction). In addition, the structure of the conveyance mechanism 32 is not limited to the above illustration.

  The moving mechanism 34 is a mechanism that reciprocates the liquid ejecting head 36 in the X direction under the control of the control unit 30. The X direction in which the liquid ejecting head 36 reciprocates is a direction that intersects (typically orthogonal) the Y direction in which the medium 22 is conveyed. The moving mechanism 34 includes a carriage 342 and a conveyance belt 344. The carriage 342 is a substantially box-shaped structure that supports the liquid ejecting head 36, and is fixed to the transport belt 344. The conveyor belt 344 is an endless belt constructed in the X direction. The liquid ejecting head 36 reciprocates in the X direction together with the carriage 342 by rotating the transport belt 344 under the control of the control unit 30. In addition, the structure of the moving mechanism 34 is not limited to the above illustration. For example, the liquid container 24 can be mounted on the carriage 342 together with the liquid ejecting head 36.

  The liquid ejecting head 36 ejects the pretreatment liquid 40 and the ink 41 supplied from the liquid container 24 onto the medium 22 under the control of the control unit 30. In parallel with the conveyance of the medium 22 by the conveyance mechanism 32 and the reciprocation by the movement mechanism 34, the liquid ejecting head 36 ejects the pretreatment liquid 40 and the ink 41 onto the medium 22, whereby a desired image is formed on the surface of the medium 22. Is formed.

(Configuration example of liquid jet head)
The liquid ejecting head 36 according to the first embodiment is configured to change the landing time difference between the pretreatment liquid 40 and the ink 41 with respect to the medium 22. A specific configuration example of such a liquid jet head 36 is shown in FIG. FIG. 2 is a plan view of a surface (hereinafter referred to as “ejection surface”) 360 facing the medium 22 in the liquid ejection head 36. Two pretreatment liquid nozzle rows LP1 and LP2 and four ink nozzle rows LI1 to LI4 are arranged on the ejection surface 360 of the liquid ejection head 36 shown in FIG. These nozzle rows are arranged in the order of the pretreatment liquid nozzle row LP1, the ink nozzle rows LI1 to LI4, and the pretreatment liquid nozzle row LP2 from the positive side to the negative side in the X direction. The pretreatment liquid nozzle rows LP1 and LP2 and the ink nozzle rows LI1 to LI4 are a set of a plurality of nozzles N arranged linearly along the Y direction. Each of the pretreatment liquid nozzle rows LP1 and LP2 and each of the ink nozzle rows LI1 to LI4 may be a plurality of rows (for example, a staggered arrangement or a staggered arrangement).

  Each of the pretreatment liquid nozzle rows LP1 and LP2 includes a plurality of pretreatment liquid nozzles N [A]. The nozzle N [A] of the pretreatment liquid nozzle row LP1 and the nozzle N [A] of the pretreatment liquid nozzle row LP2 can each inject the pretreatment liquid 40 supplied from the liquid container 24 separately. . On the other hand, the ink nozzle rows LI1 to LI4 respectively eject nozzles 41 of different colors, that is, inks 41 of four colors of cyan (C), magenta (M), yellow (Y), and black (K). N [C], N [M], N [Y], N [K] are included. The ink nozzle rows LI1 to LI4 are arranged in the X direction with a space therebetween.

  On the ejection surface 360 of the liquid ejecting head 36, two drying degree adjusting units H1 and H2 for adjusting the degree of drying of the pretreatment liquid 40 that has landed on the medium 22 are disposed. Specifically, the drying degree adjusting unit H1 is disposed between the ink nozzle rows LI1 to LI4 and the pretreatment liquid nozzle row LP1 so as to extend in a band shape in the Y direction. Between the nozzle rows LI1 to LI4 and the pretreatment liquid nozzle row LP2, they are arranged so as to extend in a band shape in the Y direction. That is, the pretreatment liquid nozzle row LP1 and the drying degree adjusting unit H1 are arranged on the positive side in the X direction of the ink nozzle rows LI1 to LI4, and the negative side in the X direction of the ink nozzle rows LI1 to LI4. The pretreatment liquid nozzle row LP2 and the drying degree adjustment unit H2 are arranged in the section. According to such an arrangement, it is possible to adjust the degree of drying of the pretreatment liquid 40 before the ink 41 is landed in both the forward movement and the backward movement of the carriage 342.

  A drying mechanism Ht for accelerating the drying of the pretreatment liquid 40 that has landed on the medium 22 is disposed in each of the drying degree adjusting units H1 and H2 in FIG. The drying mechanism Ht can be configured by a heating mechanism such as a heater. However, the drying mechanism Ht may be configured by a blower mechanism such as a fan, or may be configured to blow warm air by combining the heating mechanism and the blower mechanism. The drying mechanism Ht is turned on / off by a control signal from the control unit 30. By turning on the drying mechanism Ht, even when the drying time is short, the degree of drying can be increased as in the case where the drying time of the pretreatment liquid 40 is increased.

  According to the liquid jet head 36 having such a configuration, the controller 30 accelerates the drying of the pretreatment liquid 40 that has landed on the medium 22 by turning on and off the drying mechanism Ht of the drying degree adjusting units H1 and H2. You can choose whether or not Thereby, the drying degree of the pretreatment liquid 40 that has landed on the medium 22 can be adjusted. For example, when the pretreatment liquid 40 is ejected from the pretreatment liquid nozzle row LP1, by turning on the drying mechanism Ht of the drying degree adjusting unit H1, drying of the pretreatment liquid 40 that has landed on the medium 22 can be promoted. The ink 41 can be landed. If the drying mechanism Ht of the drying degree adjusting unit H1 is turned off, the ink 41 can be landed thereafter without promoting the drying of the pretreatment liquid 40 landed on the medium 22. In this way, the degree of drying of the pretreatment liquid 40 that has landed on the medium 22 can be adjusted.

  In the liquid jet head 36 of FIG. 2, the pretreatment liquid nozzle rows LP1 and LP2, the drying degree adjustment units H1 and H2, and the ink nozzle rows LI1 to LI4 overlap in a side view from the X direction (second direction). Have In the liquid jet head 36 of FIG. 2, the range in which the pretreatment liquid nozzles N [A] of the pretreatment liquid nozzle rows LP1 and LP2 are distributed in the X direction and the range in which the drying degree adjustment units H1 and H2 extend are respectively. In the X direction, the nozzles N [C], N [M], N [Y], and N [K] of the ink nozzle rows LI1 to LI4 overlap in a plan view. According to such an arrangement, the liquid ejecting head 36 can be downsized in the Y direction, which is the conveyance direction of the medium 22.

  FIG. 3 is a cross-sectional view focusing on any one nozzle N in the liquid jet head 36. As illustrated in FIG. 3, in the liquid jet head 36, the pressure chamber substrate 72, the vibration plate 73, the piezoelectric element 74, and the support body 75 are disposed on one side of the flow path substrate 71 and the nozzle plate 76 is disposed on the other side. Is a structure in which is arranged. The flow path substrate 71, the pressure chamber substrate 72, and the nozzle plate 76 are formed of, for example, a silicon flat plate material, and the support body 75 is formed of, for example, an injection molding of a resin material. The plurality of nozzles N are formed on the nozzle plate 76.

  In the flow path substrate 71, an opening 712, a branch flow path (restricted flow path) 714, and a communication flow path 716 are formed. The branch flow path 714 and the communication flow path 716 are through holes formed for each nozzle N, and the opening 712 is an opening continuous over a plurality of nozzles N. A space in which the accommodating portion (concave portion) 752 formed in the support body 752 and the opening 712 of the flow path substrate 71 communicate with each other is supplied from the liquid container 24 through the introduction flow path 754 of the support body 75. It functions as a common liquid chamber (reservoir) SR for storing the pretreatment liquid 40 or the ink 41.

  An opening 722 is formed for each nozzle N in the pressure chamber substrate 72. The vibration plate 73 is an elastically deformable flat plate that is installed on the surface of the pressure chamber substrate 72 opposite to the flow path substrate 71. The space sandwiched between the diaphragm 73 and the flow path substrate 71 inside each opening 722 of the pressure chamber substrate 72 is the pretreatment liquid 40 or ink 41 supplied from the common liquid chamber SR via the branch flow path 714. Functions as a pressure chamber (cavity) SC in which is filled. Each pressure chamber SC communicates with the nozzle N via the communication channel 716 of the channel substrate 71.

  A piezoelectric element 74 is formed for each nozzle N on the surface of the diaphragm 73 opposite to the pressure chamber substrate 72. Each piezoelectric element 74 is a drive element in which a piezoelectric body is interposed between electrodes facing each other. When the diaphragm 73 is vibrated by the deformation of the piezoelectric element 74 due to the supply of the drive signal, the pressure in the pressure chamber SC varies and the ink 41 in the pressure chamber SC is ejected from the nozzle N.

(Determination of media type)
The determination unit 303 of the control unit 30 according to the first embodiment determines the type of the medium 22. Specifically, the determination unit 303 determines the medium 22a having a high liquid absorbency and the medium 22b having a low liquid absorbency. Examples of the medium 22a having a high liquid absorbency include plain paper, inkjet dedicated paper, coating media, and fabrics. Examples of the medium 22b having low liquid absorbency include plastic films such as polyvinyl chloride (polyvinyl chloride), polyethylene terephthalate (PET), and polycarbonate (PC), films in which a base material is coated with a plastic or a receiving layer, metal, and printed wiring. Examples include substrates. In addition, the absorptivity of a fabric may differ with the fibers which comprise a fabric. The cloth here is assumed to be composed of fibers having high absorbability, and is included in the medium 22a having high liquid absorbency, but is not limited thereto, and is composed of fibers having low absorbency. The cloth to be used may be included in the medium 22b having a low liquid absorbency.

  For example, the ROM 301 stores in advance a media data table including a group listing the mediums 22 a having high liquid absorbency and a group listing the media 22 b having low liquid absorbency. The type of the medium 22 can be selected by the user from an operation unit (not shown) connected to the control unit 30. The discriminating unit 303 discriminates the medium 22a having a high liquid absorbency and the medium 22b having a low liquid absorbency according to which group in the medium data table the medium 22 selected by the user is included.

  Note that the method of determining the type of the medium 22 is not limited to the case described above. The determination unit 303 may determine the type of the medium 22 based on, for example, a detection signal from the medium sensor 37 illustrated in FIG. The medium sensor 37 is connected to the control unit 30. The medium sensor 37 is composed of, for example, an optical sensor, and irradiates the medium 22 with light and detects the reflected light. The discriminating unit 303 discriminates between the medium 22a having high liquid absorbency and the medium 22b having low liquid absorbency depending on whether or not the detection signal from the medium sensor 37 exceeds a predetermined threshold.

  For example, since the light reflection intensity varies depending on the type of the medium 22, the medium 22 that can determine whether the liquid absorbency is high or low can be set as the threshold value of the light reflection intensity. Specifically, in the case of a plurality of media 22 in which the higher the light reflection intensity, the lower the liquid absorbency, if the detection signal from the media sensor 37 does not exceed a predetermined threshold value, It is determined that the medium 22a has high absorbency, and if it exceeds the threshold, it is determined that the medium 22b has low liquid absorbency. The medium sensor 37 may not be provided when the type of the medium 22 is determined by the user selecting the medium 22 as described above.

  In the first embodiment, the type of the medium 22 is determined as described above, and the medium 22 is landed by turning on / off the drying mechanism Ht of the drying degree adjusting units H1, H2 according to the determined type of the medium. The degree of drying of the pretreatment liquid 40 is adjusted by selecting whether to accelerate the drying of the pretreatment liquid 40. Accordingly, the reactivity between the pretreatment liquid 40 and the ink 41 can be increased and the print image quality can be improved regardless of the type of medium.

(Relationship between media type and degree of drying of pretreatment liquid)
Hereinafter, the relationship between the type of the medium and the degree of drying of the pretreatment liquid 40 will be described. The degree of drying of the pretreatment liquid 40 here is represented by the drying time of the pretreatment liquid 40 when a drying mechanism such as a heater or a fan is not used. The drying time of the pretreatment liquid 40 is defined as the time from the landing of the pretreatment liquid 40 to the arrival of the ink 41 (landing time difference). The longer the time it takes for the ink 41 to land, the longer the drying time of the pretreatment liquid 40, so the degree of drying of the pretreatment liquid 40 also increases. Conversely, the shorter the time until the ink 41 lands, the shorter the drying time of the pretreatment liquid 40, and thus the degree of drying of the pretreatment liquid 40 becomes smaller.

  FIG. 4 shows a state of the pretreatment liquid 40 at the time of landing and immediately before ink landing in four cases 1 to 4 where the drying time of the pretreatment liquid 40 is changed for different types of media, specifically, the pretreatment liquid. It is a figure for demonstrating the surface residual amount of the reactive component in 40, and the surface residual amount of solvent components, such as a water | moisture content and a solvent. The medium 22 having a different type is either a medium 22a having a high liquid absorbency (for example, coated paper having an ink absorption layer) or a medium 22b having a low liquid absorbency (for example, a plastic film such as vinyl chloride). It is. The drying time in FIGS. 4 and 5 is the time from the landing of the pretreatment liquid 40 to the landing of the ink 41 (landing time difference), as described above, and represents the degree of drying.

  In FIG. 4, Case 1 is a case where the pretreatment liquid 40 has a long drying time (landing time difference) when the pretreatment liquid 40 is landed on the highly absorbent medium 22a. It is a short case. Case 3 is a case where the drying time of the pretreatment liquid 40 is long when the pretreatment liquid 40 is landed on the medium 22b having low absorbency, and Case 4 is a case where the drying time is short. FIG. 5 is a diagram for explaining the state of the ink 41 after ink landing in the cases 1 to 4 of FIG. In FIG. 5, the black portion is the ink 41.

  The surface residual amount in FIG. 4 is the residual amount of the pretreatment liquid 40 remaining on the surface of the medium 22a or 22b immediately before ink landing. The surface residual amount of the reaction component is the surface residual amount of the reaction component of the constituent components of the pretreatment liquid 40, and the surface residual amount of the solvent component is the surface residual amount of the solvent component of the constituent components of the pretreatment liquid 40. Amount. The surface remaining amount of the pretreatment liquid 40 varies depending on the absorbability of the medium and the drying time of the pretreatment liquid. Moreover, among the constituent components of the pretreatment liquid 40, the solvent component is easier to dry and penetrate into the medium than the reaction component. It depends on the drying time of the pretreatment liquid. In FIG. 4, when the drying time is long, it is expressed as “long”, when it is short, it is expressed as “short”, when the surface residual amount is large, it is expressed as “many”, and when it is small, it is expressed as “low”.

  First, the highly absorbent medium 22a in case 1 and case 2 of FIG. 4 will be described. As shown in Case 1 of FIG. 4, when the drying time of the pretreatment liquid 40 is long in the highly absorbent medium 22 a, the surface residual amounts of the reaction component and the solvent component of the pretreatment liquid 40 are both “small”. It becomes. That is, in the medium 22a having high absorbability, the pretreatment liquid 40 is likely to permeate. Therefore, if the drying time of the pretreatment liquid 40 is long, the pretreatment liquid 40 permeates immediately before the landing of the ink 41. As the drying proceeds, the amount of the reaction component remaining on the surface becomes too small. Therefore, in this case, when the ink is landed as shown in Case 1 of FIG. 5, the surface residual amount of the reaction component of the pretreatment liquid 40 is small, and thus the reactivity between the pretreatment liquid 40 and the ink 41 is reduced. Also lower. For this reason, the dots of the ink 41 that have landed on the surface of the medium 22a spread and easily aggregate so as to overlap. Therefore, in the case 1 of FIG. 4, there is a possibility that the print image quality is deteriorated.

  On the other hand, as shown in Case 2 of FIG. 4, in the medium 22a having high absorbency, when the drying time of the pretreatment liquid 40 is short, the surface residual amount of the reaction component of the pretreatment liquid 40 becomes “large”. The surface residual amount of the solvent component is “medium”. In this case, since the drying time of the pretreatment liquid 40 is short even if the medium 22a has high absorbency, the pretreatment liquid 40 does not permeate too much immediately before the landing of the ink 41. The penetration of the reaction component can be suppressed, and the surface residual amount of the reaction component can be increased. For this reason, when the ink 41 is landed as shown in the case 2 of FIG. 5, the reactivity with the ink 41 can be improved. In case 2 of FIG. 4, since the surface residual amount of the solvent component is relatively high just before ink landing, when the ink 41 is landed on the medium 22a, the dots of the landed ink 41 are the medium 22a. Try to move on the surface. However, in the highly absorbent medium 22a, as indicated by the arrow in case 2 in FIG. 5, the ink component immediately permeates the medium 22a immediately after the ink 41 has landed on the medium 22a. It is stable on the surface of 22a and aggregates without overlapping each other. Therefore, in the case 2 of FIG. 4, the print image quality can be improved.

  Next, the medium 22b having low absorbency in the case 3 and the case 4 of FIG. 4 will be described. As shown in Case 3 of FIG. 4, in the medium 22b having low absorbability, when the drying time of the pretreatment liquid 40 is long, the surface residual amount of the reaction component of the pretreatment liquid 40 becomes “large”, and the solvent component The remaining amount on the surface is “small”. That is, in the medium 22b having low absorbability, the pretreatment liquid 40 is difficult to permeate, and thus the surface residual amount of the reaction components increases. However, if the drying time of the pretreatment liquid 40 is long, a large amount remains on the medium 22b surface. The solvent component of the pretreatment liquid 40 can be sufficiently dried. In the pretreatment liquid 40 immediately before ink landing in case 3 in FIG. 4, the pretreatment liquid 40 immediately after landing is shown by being overlapped with a dotted line. This represents that the drying proceeds from immediately after the landing of the pretreatment liquid 40 to immediately before the ink landing, and the surface residual amount of the pretreatment liquid 40 is reduced. When the ink 41 is landed as shown in Case 3 in FIG. 5 in a state where the drying of the pretreatment liquid 40 has sufficiently progressed in this way, the amount of reactive components remaining on the surface is large, and thus the reactivity with the ink 41 is increased. Can be improved. Further, since the amount of the solvent component remaining on the surface is small, the dots of the ink 41 are stable without moving on the surface of the medium 22b and are aggregated without overlapping each other. Thus, the position after the landing of the ink 41 can be stabilized. Therefore, in case 3 of FIG. 4, the print image quality can be improved.

  On the other hand, as shown in Case 4 of FIG. 4, when the drying time of the pretreatment liquid 40 is long in the medium 22b having low absorbency, both the surface residual amounts of the reaction component and the solvent component of the pretreatment liquid 40 are “large”. " In the medium 22b having low absorbability, the pretreatment liquid 40 is difficult to permeate, so that the amount of the surface of the pretreatment liquid 40 increases. The solvent component of the treatment liquid 40 cannot be sufficiently dried. When the ink 41 is landed as shown in Case 4 in FIG. 5 in a state where the pretreatment liquid 40 is not sufficiently dried, the ink 41 landed on the medium 22b because the solvent component of the pretreatment liquid 40 is large. Even if agglomerates, for example, the agglomerated ink 41 as shown by an arrow may slide on the surface of the medium 22b and shift from the landing position. Therefore, in the case 4 of FIG. 4, there is a possibility that the print image quality is deteriorated.

  According to the above, in order to improve the print image quality, in the medium 22a having high absorbency, the pretreatment liquid 40 is likely to permeate, and the surface residual amount of the reaction component in the pretreatment liquid 40 is likely to be reduced. It can be seen that it is preferable to shorten the length of the medium so as to prevent the reaction component from penetrating into the medium 22a and to prevent it from being dried too much. On the other hand, in the medium 22b having low absorbability, the pretreatment liquid 40 is difficult to permeate, and the remaining amount of the solvent component in the pretreatment liquid 40 is difficult to dry. Therefore, the degree of drying is adjusted by increasing the drying time. By doing so, it is understood that it is preferable to promote the drying of the solvent component and stabilize the position of the ink 41 after landing on the medium 22b.

  In the first embodiment, in the medium 22a with high absorbency, the reaction component in the pretreatment liquid 40 is adjusted while adjusting the degree of drying by turning off the drying mechanism Ht of the degree-of-drying adjusting unit H1 and not promoting drying. Can be suppressed. On the other hand, in the medium 22b having low absorbency, the drying mechanism Ht of the drying degree adjusting unit H1 is turned on to promote drying of the solvent component in the pretreatment liquid 40, and after landing on the medium 22b. The position of the ink 41 can be stabilized. Accordingly, the reactivity between the pretreatment liquid 40 and the ink 41 can be increased and the print image quality can be improved regardless of the type of the medium 22.

(Liquid jetting method of the first embodiment)
Based on the above, the liquid ejecting method according to the first embodiment will be described by taking the control of the liquid ejecting head 36 according to the first embodiment as an example. FIG. 6 is a flowchart illustrating control of the liquid ejecting head 36 in print control. The control unit 30 reads a predetermined program from the ROM 301 in accordance with an instruction from the management apparatus, and executes print control on the medium 22. In the printing control, the control unit 30 controls the liquid ejecting head 36 shown in FIG.

  First, in step S101, the determination unit 303 determines the type of the medium 22 to be printed. For example, the determination unit 303 determines the type of the medium 22 based on the above-described medium data table. Specifically, the determination unit 303 compares the medium 22 selected by the user with the medium 22 in the medium data table, and determines whether the medium 22 is the medium 22a having high absorbency or the medium 22b having low absorbency. In step S101, the medium 22 may be determined based on the detection signal from the medium sensor 37 as described above.

  When the determination unit 303 determines that the medium 22a is highly absorbent in step S101, the control unit 30 selects not to promote drying of the pretreatment liquid 40 in step S102, and the drying degree adjustment units H1 and H2 are selected. The drying mechanism Ht is turned off. At this time, if the drying mechanism Ht of the drying degree adjusting units H1 and H2 is already off, it is left as it is. Subsequently, in step S104, the control unit 30 ejects the pretreatment liquid 40 from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1 to land on the medium 22a. In step S105, the ink 41 of a required color is ejected from the nozzles N [C], N [M], N [Y], and N [K] of the ink nozzle rows LI1 to LI4 to land on the medium 22a.

  On the other hand, when the determination unit 303 determines that the medium 22b has low absorbency in step S101, the control unit 30 selects to promote drying of the pretreatment liquid 40 in step S103, and the drying is performed. The drying mechanism Ht of the degree adjusting units H1, H2 is turned on. At this time, if the drying mechanism Ht of the drying degree adjusting units H1 and H2 is already on, it is left as it is. Subsequently, in step S104, the control unit 30 ejects the pretreatment liquid 40 from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1 to land on the medium 22b. In step S105, the ink 41 of a necessary color is ejected from the nozzles N [C], N [M], N [Y], and N [K] of the ink nozzle rows LI1 to LI4 to land on the medium 22b.

  In steps S104 and S105, in the liquid jet head 36 having the configuration shown in FIG. 2, when the carriage 342 moves forward (when moving to the positive side in the X direction), the pretreatment liquid nozzle N [ While the pretreatment liquid 40 is ejected from A], the ink 41 can also be ejected. According to this, the time from the landing of the pretreatment liquid 40 to the landing of the ink 41 can be shortened so that there is almost no time difference. At this time, in the medium 22a having high absorbency, the drying mechanism Ht of the drying degree adjusting unit H1 is off, and thus drying is not promoted. Therefore, the ink is not absorbed before the reaction component of the pretreatment liquid 40 penetrates too much into the medium 22a. 41 can be landed. Therefore, for the highly absorbent medium 22a, the drying mechanism Ht of the drying degree adjusting unit H1 is turned off, which is the same as the case where the drying time of the pretreatment liquid 40 is shortened as in the case 2 of FIG. Thus, as in Case 2 of FIG. 5, the reactivity between the pretreatment liquid 40 and the ink 41 can be improved, and the print image quality can be improved.

  On the other hand, in the medium 22b having low absorbency, the drying mechanism Ht of the drying degree adjusting unit H1 is on, so that the drying of the pretreatment liquid 40 remaining in the medium 22b can be promoted and the ink 41 can be landed. . Therefore, for the medium 22b having a low absorbency, the drying mechanism Ht of the drying degree adjusting unit H1 is turned on so that the drying time of the pretreatment liquid 40 is increased as in the case 3 of FIG. Thus, the position of the ink 41 that has landed on the medium 22b can be stabilized as in the case 3 of FIG. 5, so that the print image quality can be improved.

  As described above, according to the liquid ejecting head 36 of the first embodiment, the drying mechanism Ht of the drying degree adjusting unit H1 is turned on or off according to the type of the medium 22, so that it does not depend on the type of the medium 22. The reactivity with the ink 41 can also be improved, and the print image quality can be improved. Further, instead of turning the drying mechanism Ht on or off, the strength of the drying mechanism Ht may be adjusted. In the liquid ejecting head 36 having the configuration shown in FIG. 2, the front side of the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP2 is moved forward even when the carriage 342 moves backward (when it moves to the negative side in the X direction). The ink 41 can also be ejected while ejecting the treatment liquid 40. In this case, the same effect as that of the carriage 342 can be obtained. As described above, according to the liquid ejecting head 36 of FIG. 2, the pretreatment liquid 40 and the ink 41 are transferred to the medium while adjusting the degree of drying of the pretreatment liquid 40 both during the forward movement and the backward movement of the carriage 342. 22, the print quality can be improved and the printing speed can be increased as compared with the case where the pretreatment liquid 40 and the ink 41 are landed on the medium 22 during forward movement and backward movement. it can.

(First modification of the first embodiment)
A liquid jet head 36 according to a first modification of the first embodiment will be described. In the first modified example, a case where the pretreatment liquid nozzle row and the drying degree adjustment unit are arranged on one side in the X direction of the ink nozzle row will be described as an example. FIG. 7 is a plan view of the ejection surface 360 of the liquid ejection head 36 according to the first modification of the first embodiment. The liquid ejecting head 36 of FIG. 7 differs from that of FIG. 2 in that only the ink nozzle arrays LI1 to LI4, the pretreatment liquid nozzle array LP1 on the positive side in the X direction, and the drying degree adjusting unit H1 (drying mechanism Ht) are ejected. This is a point arranged on the surface 360.

  According to the liquid jet head 36 of FIG. 7, during the forward movement of the carriage 342 (when moving to the positive side in the X direction), the pretreatment liquid 40 from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1. Ink 41 can also be ejected while ejecting. At this time, similarly to the liquid ejecting head 36 of FIG. 2, by turning on or off the drying mechanism Ht of the drying degree adjusting unit H 1 according to the type of the medium 22, the ink can be used regardless of the type of the medium 22. The reactivity with 41 can also be improved, and the print image quality can be improved. 7, only the ink nozzle rows LI1 to LI4, the pretreatment liquid nozzle row LP2 on the negative side in the X direction, and the drying degree adjusting unit H2 (drying mechanism Ht) are arranged on the ejection surface 360. It may be.

(Second modification of the first embodiment)
A liquid jet head 36 according to a second modification of the first embodiment will be described. FIG. 8 is a plan view of the ejection surface 360 of the liquid ejection head 36 according to the second modification of the first embodiment. The liquid ejecting head 36 of FIG. 8 differs from that of FIG. 7 in that the pretreatment liquid nozzle row LP1 is on the negative side in the Y direction (that is, upstream in the transport direction of the medium 22) as viewed from the ink nozzle rows LI1 to LI4. It is a point to be placed. For example, assuming a straight line G parallel to the X direction on the ejection surface 360, the first region A on the positive side in the Y direction (downstream in the conveyance direction of the medium 22) from the straight line G and the negative direction in the Y direction from the straight line G. It is divided into the second region B on the side (upstream side in the conveyance direction of the medium 22). The ink nozzle rows LI1 to LI4 are arranged in the first region A, and the pretreatment liquid nozzle row LP1 and the drying degree adjusting unit H1 (including the drying mechanism Ht) are arranged in the second region B.

  According to the liquid ejecting head 36 in FIG. 8, when the carriage 342 moves forward, the pretreatment liquid 40 is ejected from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1 and then the medium 22 is moved in the Y direction. The ink 41 can be ejected onto the portion where the pretreatment liquid 40 has landed when the carriage 342 is moved backward. At this time, similarly to the liquid jet head 36 of FIG. 7, the degree of drying of the pretreatment liquid 40 can be adjusted by turning on or off the drying mechanism Ht of the degree-of-drying adjusting unit H1 according to the type of the medium 22. . Therefore, the reactivity with the ink 41 can be improved regardless of the type of the medium 22, and the print image quality can be improved.

  In the liquid jet head 36 of FIG. 8, the pretreatment liquid nozzle row LP1 and the drying degree adjusting unit H1 (including the drying mechanism Ht) are not limited to the second region B, but the first region A and the second region B. You may arrange separately in both. According to such a configuration, the pretreatment liquid 40 is selected by selecting either the nozzle N [A] in the first area A or the nozzle N [A] in the second area B from the pretreatment liquid nozzle row LP1. By ejecting, the landing time difference from the ink 41 ejected from the nozzles N [C], N [M], N [Y], and N [K] of the ink nozzle rows LI1 to LI4 and then landed on the medium 22 is calculated. Since it can be changed, the drying time of the pretreatment liquid 40 can also be adjusted.

(Third Modification of First Embodiment)
A liquid jet head 36 according to a third modification of the first embodiment will be described. In the third modification, a liquid ejecting head 36 that can not only land the pretreatment liquid 40 on the medium 22 before ink landing but also can land the posttreatment liquid 42 after ink landing is described as an example. FIG. 9 is a plan view of the ejection surface 360 of the liquid ejection head 36 according to the third modification example of the first embodiment.

  The post-treatment liquid 42 used in the third modification is a liquid that can improve the gloss, light resistance, and the like of a printed image by covering the medium 22 after ink landing. The pretreatment liquid 40 is the same as that described above. In the liquid container 24 shown in FIG. 9, the pretreatment liquid 40 and the posttreatment liquid 42 are separately stored. In FIG. 9, the liquid container 24 is illustrated as one element for convenience, but a configuration in which the pretreatment liquid 40, the posttreatment liquid 42, and a plurality of types of ink 41 are stored in separate liquid containers 24 is also employed. Can be done.

  9 differs from FIG. 2 in that the pretreatment liquid nozzle row LP1 ′ and the pretreatment liquid nozzle are arranged on the positive side in the X direction of the drying degree adjusting unit H1 from the positive side to the negative side in the X direction. This is the point where the rows LP1 '' are arranged in this order and spaced from one another. In addition, the pretreatment liquid nozzle row LP2 ′ and the pretreatment liquid nozzle row LP2 ″ are spaced apart from each other in this order from the negative side to the positive side in the X direction of the drying degree adjusting unit H2. The arrangement is also different.

  The pretreatment liquid nozzle rows LP1 ′ and LP2 ′ are a set of a plurality of pretreatment liquid nozzles N [A] arranged linearly along the Y direction, and the posttreatment liquid nozzle rows LP1 ″ and LP2 ″. Is a set of a plurality of post-treatment liquid nozzles N [B] arranged linearly along the Y direction. The pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1 ′ and the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP2 ′ are each separately supplied from the liquid container 24. Can be injected. The post-processing liquid nozzle row LP1 ″, the post-processing liquid nozzle N [B], and the post-processing liquid nozzle row LP2 ″, the post-processing liquid nozzle N [B] are separately supplied from the liquid container 24. The liquid 42 can be ejected. The configuration of the ink nozzle rows LI1 to LI4 is the same as that shown in FIG.

  According to the liquid ejecting head 36 of FIG. 9, when the carriage 342 moves forward, the ink nozzle rows LI1 to LI4 are ejected while ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1 ′. The ink 41 is ejected from the post-treatment liquid nozzle row LP2 ″, and the post-treatment liquid 42 can also be ejected from the post-treatment liquid nozzle N [B]. On the other hand, when the carriage 342 moves backward, the ink 41 is ejected from the ink nozzle arrays LI1 to LI4 while ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle array LP2 ′. The post-processing liquid 42 can also be ejected from the post-processing liquid nozzle N [B] of the processing liquid nozzle row LP1 ″.

  Depending on the type of the medium 22, the drying mechanism Ht of the drying degree adjusting unit H1 is turned on or off when the carriage 342 moves forward, and the drying mechanism Ht of the drying degree adjusting unit H2 is turned on or off when the carriage 342 moves backward. By doing so, the degree of drying of the pretreatment liquid 40 can be adjusted before ink landing. Therefore, the reactivity with the ink 41 can be improved regardless of the type of the medium 22, and the print image quality can be improved. Furthermore, since the post-treatment liquid 42 can also be ejected after ink landing, the gloss and light resistance can be improved while improving the image quality of the printed image.

  In the configuration of FIG. 9, the pretreatment liquid nozzle rows LP1 ′ and LP2 ′, the posttreatment liquid nozzle rows LP1 ″ and LP2 ″, the drying degree adjusting units H1 and H2, and the ink nozzle rows LI1 to LI4 , And a portion overlapping in the side view from the X direction (second direction). In the liquid ejecting head 36 of FIG. 9, the range in which the pretreatment liquid nozzles N [A] of the pretreatment liquid nozzle rows LP1 ′ and LP2 ′ are distributed in the X direction and the posttreatment liquid nozzle rows LP1 ″ and LP2 ″. The range in which the post-treatment liquid nozzles N [B] are distributed and the range in which the drying degree adjustment units H1 and H2 extend are the nozzles N [C], N [M], and N in the ink nozzle rows LI1 to LI4 in the X direction. It overlaps in a plan view in a range where [Y] and N [K] are distributed. When a nozzle row is added to the ejection surface 360 of the liquid ejecting head 36 as in the post-processing liquid nozzle rows LP1 ″ and LP2 ″, by adding the nozzle row in the X direction of the liquid ejecting head 36, Compared to the case where a nozzle row is added in the Y direction of the liquid ejecting head 36, it can be prevented from becoming large in the Y direction, which is the conveyance direction of the medium 22. Accordingly, even if a nozzle row is added, the liquid ejecting head 36 can be reduced in size in the Y direction.

(Fourth modification of the first embodiment)
A liquid jet head 36 according to a fourth modification of the first embodiment will be described. The fourth modified example is another example of the liquid ejecting head 36 that can not only land the pretreatment liquid 40 on the medium 22 before ink landing but also land the posttreatment liquid 42 after ink landing. FIG. 10 is a plan view of the ejection surface 360 of the liquid ejection head 36 according to the fourth modification example of the first embodiment. The pretreatment liquid 40 and the posttreatment liquid 42 used in the fourth modification are the same as those used in the third modification.

  10 differs from FIG. 2 in that the pretreatment liquid nozzle row LP1 ′ on the upstream side in the transport direction of the medium 22 (the negative side in the Y direction) and the medium 22 are different from the nozzle row LP1. This is the point at which the post-processing liquid nozzle row LP1 ″ on the downstream side in the transport direction (positive side in the Y direction) is arranged. Further, instead of the pretreatment liquid nozzle row LP2, a pretreatment liquid nozzle row LP2 ′ on the upstream side in the conveyance direction of the medium 22 and a post treatment liquid nozzle row LP2 ″ on the downstream side in the conveyance direction of the medium 22 are arranged. The point is also different. For example, assuming a straight line G parallel to the X direction on the ejection surface 360, the first region A on the positive side in the Y direction (downstream in the conveyance direction of the medium 22) from the straight line G and the negative direction in the Y direction from the straight line G. It is divided into the second region B on the side (upstream side in the conveyance direction of the medium 22). The pretreatment liquid nozzle row LP1 ′ and the pretreatment liquid nozzle row LP2 ′ are arranged in the second region B, and the posttreatment liquid nozzle row LP1 ″ and the posttreatment liquid nozzle row LP2 ″ are arranged in the first region A. Is done. The ink nozzle rows LI1 to LI4 are arranged from the first area A to the second area B. The ink nozzle rows LI1 to LI4 may be separately arranged in the first area A and the second area B.

  The pretreatment liquid nozzle row LP1 ′ and the pretreatment liquid nozzle row LP2 ′ include a plurality of pretreatment liquid nozzles N [A] that eject the pretreatment liquid 40 supplied from the liquid container 24, and the posttreatment liquid nozzle row LP1. The post-treatment liquid nozzle row LP2 '' includes a plurality of post-treatment liquid nozzles N [B] that eject the pre-treatment liquid 40 supplied from the liquid container 24. The configuration of the ink nozzle rows LI1 to LI4 is the same as that shown in FIG. 2, and is arranged from the upstream region to the downstream region in the Y direction. The range in which the pretreatment liquid nozzles N [A] of the pretreatment liquid nozzle rows LP1 ′ and LP2 ′ are distributed in the X direction is the nozzles N [C] and N of the ink nozzle rows LI1 to LI4 in the second region B in the X direction. It overlaps in a plan view (side view from the X direction) in a range where [M], N [Y], and N [K] are distributed. In addition, the range in which the post-processing liquid nozzle rows LP1 ″ and LP2 ″ in the X direction are distributed is the range of the nozzles N [B1 to LI4 in the first region A in the X direction. C], N [M], N [Y], and N [K] are overlapped in a plan view (side view from the X direction).

  In the liquid ejecting head 36 of FIG. 10, when the carriage 342 moves forward, ink is ejected from the ink nozzle rows LI1 to LI4 while ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1 ′. 41 can be ejected, and when the carriage 342 moves backward, ink is ejected from the ink nozzle rows LI1 to LI4 while ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle row LP1 ″. 41 can be injected. Further, during the forward movement of the carriage 342, the post-processing liquid 42 is ejected from the post-processing liquid nozzle N [B] of the post-processing liquid nozzle array LP2 ″ while ejecting the ink 41 from the ink nozzle arrays LI1 to LI4. When the carriage 342 is moved back, the post-processing liquid 42 is ejected from the post-processing liquid nozzle N [B] of the post-processing liquid nozzle array LP1 ″ while ejecting the ink 41 from the ink nozzle arrays LI1 to LI4. it can.

  According to the liquid ejecting head 36 of FIG. 10 like this, as with the liquid ejecting head 36 of FIG. 2, the drying mechanism Ht of the drying degree adjusting unit H1 is turned on when the carriage 342 moves forward according to the type of the medium 22. Alternatively, the degree of drying of the pretreatment liquid 40 can be adjusted by turning off and turning on or off the drying mechanism Ht of the drying degree adjusting unit H2 when the carriage 342 moves backward. Therefore, the reactivity with the ink 41 can be improved regardless of the type of the medium 22, and the print image quality can be improved. Furthermore, since the post-treatment liquid 42 can also be ejected after ink landing, the gloss and light resistance can be improved while improving the image quality of the printed image. In the liquid ejecting head 36 of FIG. 10, the pretreatment liquid 40 is ejected simultaneously with the ink 41, and the degree of drying is adjusted by turning on or off the drying mechanism Ht of the degree-of-drying adjustment unit H1. The ink 41 can be ejected after the image is completed.

Second Embodiment
A second embodiment of the present invention will be described. In 1st Embodiment-3rd Embodiment, although the drying mechanism Ht was provided in the drying degree adjustment parts H1 and H2, and the case where the drying degree of the pretreatment liquid 40 was adjusted was illustrated, in 2nd Embodiment, the drying degree When adjusting nozzles H1 and H2 are provided with an adjustment nozzle row, and either the adjustment nozzle row or the pretreatment liquid nozzle row is selected and the pretreatment liquid 40 is sprayed to adjust the degree of drying of the pretreatment liquid 40 Will be described. In addition, about the element which an effect | action and function are the same as that of 1st Embodiment in each form illustrated below, the code | symbol used by description of 1st Embodiment is diverted, and each detailed description is abbreviate | omitted suitably.

  FIG. 10 is a plan view of the ejection surface 360 of the liquid ejection head 36 according to the second embodiment. The liquid ejecting head 36 of FIG. 11 is different from that of FIG. 2 in that adjustment nozzle arrays Lh1 and Lh2 are arranged in the drying degree adjustment units H1 and H2, respectively, instead of the drying mechanisms Ht and Ht. The adjustment nozzle rows Lh1 and Lh2 are a set of a plurality of pretreatment liquid nozzles N [A] arranged linearly along the Y direction. The pretreatment liquid nozzle N [A] of the adjustment nozzle row Lh1 and the pretreatment liquid nozzle N [A] of the adjustment nozzle row Lh2 can each inject the pretreatment liquid 40 supplied from the liquid container 24 separately. ing.

  In the configuration of FIG. 11, the distance in the X direction between the adjustment nozzle row Lh1 and the ink nozzle rows LI1 to LI4 is different from the distance in the X direction between the pretreatment liquid nozzle row LP1 and the ink nozzle rows LI1 to LI4. Accordingly, by selecting either the adjustment nozzle row Lh1 or the pretreatment liquid nozzle row LP1 and ejecting the pretreatment liquid 40, the drying time of the pretreatment liquid 40 until the ink 41 is landed can be changed. The degree of drying of the pretreatment liquid 40 can be adjusted. In FIG. 11, the adjustment nozzle row Lh1 is closer to the ink nozzle rows LI1 to LI4 than the pretreatment liquid nozzle row LP1. Therefore, by spraying the pretreatment liquid 40 from the adjustment nozzle row Lh1, the drying time of the pretreatment liquid 40 can be shortened, and by spraying the pretreatment liquid 40 from the pretreatment liquid nozzle row LP1, The drying time of the treatment liquid 40 can be lengthened.

  Similarly, the distance in the X direction between the adjustment nozzle row Lh2 and the ink nozzle rows LI1 to LI4 is different from the distance in the X direction between the pretreatment liquid nozzle row LP2 and the ink nozzle rows LI1 to LI4. Therefore, by selecting either the adjustment nozzle row Lh2 or the pretreatment liquid nozzle row LP2 and ejecting the pretreatment liquid 40, the drying time of the pretreatment liquid 40 until the ink 41 is landed can be changed. The degree of drying of the pretreatment liquid 40 can be adjusted. In FIG. 11, the adjustment nozzle row Lh2 is closer to the ink nozzle rows LI1 to LI4 than the pretreatment liquid nozzle row LP2. For this reason, the drying time of the pretreatment liquid 40 can be shortened by ejecting the pretreatment liquid 40 from the adjustment nozzle row Lh2, and the pretreatment liquid 40 can be pretreated by ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle LP2. The drying time of the liquid 40 can be lengthened.

(Liquid jetting method of the second embodiment)
Based on the above, the liquid ejecting method of the second embodiment will be described by taking the control of the liquid ejecting head 36 in FIG. 11 as an example. FIG. 12 is a flowchart illustrating control of the liquid ejecting head 36 in print control. The control unit 30 reads a predetermined program from the ROM 301 in accordance with an instruction from the management apparatus, and executes print control on the medium 22. In the printing control, the control unit 30 controls the liquid ejecting head 36 shown in FIG.

  First, in step S401, the determination unit 303 determines the type of the medium 22 to be printed. Specifically, the same processing as step S101 in FIG. 6 is performed. When the determination unit 303 determines that the medium 22a has a high absorbency in step S401, the control unit 30 moves the carriage 342 in the forward or backward direction while moving the adjustment nozzle row Lh1 during the forward movement in step S402. By selecting and adjusting nozzle row Lh2 at the time of reverse movement, the nozzles N [1 to LI4 of the ink nozzle rows LI1 to LI4 are applied to the portions where the pretreatment liquid 40 has landed in step S404 while ejecting the pretreatment liquid 40. C], N [M], N [Y], and N [K] eject ink 41 of a necessary color to land on the medium 22a.

  On the other hand, when the determination unit 303 determines that the medium 22b has low absorbency in step S401, the control unit 30 moves the carriage 342 forward or backward while the forward movement in step S403. Selects the pretreatment liquid nozzle row LP1 and selects the pretreatment liquid nozzle row LP2 at the time of return, so that the pretreatment liquid 40 is ejected in step S404 while the pretreatment liquid 40 is ejected. The ink 41 of a necessary color is ejected from the nozzles N [C], N [M], N [Y], and N [K] of the ink nozzle rows LI1 to LI4 to land on the medium 22a.

  According to the printing control of the second embodiment, for the highly absorbent medium 22a, the adjustment nozzle row Lh1 or the adjustment nozzle row Lh2 is selected when the carriage 342 moves forward or backward. Thus, since the drying time of the pretreatment liquid 40 can be shortened as in the case 2 of FIG. 4, the ink 41 can be landed before the reaction component of the pretreatment liquid 40 has permeated the medium 22a too much. . Accordingly, the reactivity between the pretreatment liquid 40 and the ink 41 can be improved as in the case 2 of FIG. 5, and the print image quality can be improved.

  On the other hand, for the medium 22b having a low absorbency, the pretreatment liquid nozzle row LP1 or the pretreatment liquid nozzle row LP2 is selected when the carriage 342 moves forward or backward, so that the case 3 in FIG. Thus, since the drying time of the pretreatment liquid 40 can be lengthened, drying of the pretreatment liquid 40 remaining in the medium 22b can be promoted. As a result, the position of the ink 41 that has landed on the medium 22b can be stabilized as in the case 3 of FIG. 5, so that the print image quality can be improved.

  As described above, according to the liquid jet head 36 of the second embodiment, the degree of drying of the pretreatment liquid 40 can be adjusted by changing the drying time of the pretreatment liquid 40 according to the type of the medium 22. Regardless of the type, the reactivity with the ink 41 can be improved, and the print image quality can be improved. In the liquid ejecting head 36 having the configuration shown in FIG. 11, the ink 41 can be ejected while adjusting the drying time of the pretreatment liquid 40 both when the carriage 342 moves forward and when the carriage 342 moves backward. However, the printing speed can also be increased.

<Third Embodiment>
A third embodiment of the present invention will be described. The drying degree adjustment unit may not include the drying mechanism (first embodiment to third embodiment) and the adjustment nozzle row (second embodiment), and the distance between the pretreatment liquid nozzle row and the ink nozzle row. It can also be used as an adjustment area for adjusting. In the third embodiment, the degree of drying of the pretreatment liquid 40 is adjusted by setting the drying degree adjustment unit as an adjustment region having a width for adjusting the distance between the pretreatment liquid nozzle row and the ink nozzle row. An example of the case will be described.

  FIG. 13 is a plan view of the ejection surface 360 of the liquid ejection head 36 according to the third embodiment. The liquid ejecting head 36 in FIG. 13 is different from that in FIG. 2 in that the drying degree adjusting units H1 and H2 do not have a drying mechanism Ht. The drying degree adjustment units H1 and H2 in FIG. 13 are adjustment regions H1 ′ and H2 ′ having different widths. The adjustment region H1 ′ has a width W1 for adjusting the distance between the pretreatment liquid nozzle row LP1 and the ink nozzle rows LI1 to LI4, and the adjustment region H2 ′ includes the pretreatment liquid nozzle row LP2 and the ink nozzle. It has a width W2 for adjusting the distance between the rows LI1 to LI4. Here, the width W1 of the adjustment region H1 ′ and the width W2 of the adjustment region H2 ′ are the widths in the X direction.

  In the configuration of FIG. 13, the width W1 in the X direction of the adjustment region H1 ′ is narrower and the width W2 in the X direction of the adjustment region H1 ′ is wider. For this reason, the distance between the pretreatment liquid nozzle row LP1 and the ink nozzle rows LI1 to LI4 is shorter, and the distance between the pretreatment liquid nozzle row LP2 and the ink nozzle rows LI1 to LI4 is longer. Therefore, by selecting the width W1 of the narrower adjustment region H1 ′ and ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle row LP1, the drying time of the pretreatment liquid 40 until the ink 41 lands on the medium. Can be shortened. Further, by selecting the width W2 of the wider adjustment region H1 ′ and ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle row LP2, the drying time of the pretreatment liquid 40 until the ink 41 lands on the medium. Can be lengthened.

  According to such a configuration of FIG. 13, by selecting either the width W1 of the adjustment region H1 ′ or the width W2 of the adjustment region H2 ′, the drying time of the pretreatment liquid 40 until the ink 41 is landed can be reduced. Since it can be changed, the degree of drying of the pretreatment liquid 40 can be adjusted. Specifically, the drying time of the pretreatment liquid 40 can be shortened by ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle row LP1 on the adjustment region H1 ′ side while moving the carriage 342 forward. On the other hand, the drying time of the pretreatment liquid 40 can be extended by ejecting the pretreatment liquid 40 from the pretreatment liquid nozzle row LP2 on the adjustment region H2 ′ side while moving the carriage 342 backward.

(Liquid ejection method of the third embodiment)
Based on the above, the liquid ejecting method of the third embodiment will be described by taking the control of the liquid ejecting head 36 of FIG. 13 as an example. FIG. 14 is a flowchart illustrating control of the liquid ejecting head 36 in print control. The control unit 30 reads a predetermined program from the ROM 301 in accordance with an instruction from the management apparatus, and executes print control on the medium 22. In the printing control, the control unit 30 controls the liquid ejecting head 36 shown in FIG. 14 while controlling the conveyance of the medium 22.

  First, in step S501, the determination unit 303 determines the type of the medium 22 to be printed. Specifically, the same processing as step S101 in FIG. 6 is performed. When the determination unit 303 determines that the medium 22a has high absorbency in step S501, the control unit 30 selects the width W2 of the narrower adjustment region H1 ′ in step S502 while moving the carriage 342 forward. Then, while the pretreatment liquid 40 is ejected from the pretreatment liquid nozzle row LP1, the nozzles N [C] and N [M] of the ink nozzle rows LI1 to LI4 are applied to the portions where the pretreatment liquid 40 has landed in step S504. , N [Y], and N [K], the ink 41 of a necessary color is ejected to land on the medium 22a.

  On the other hand, if the determination unit 303 determines that the medium 22b has low absorbency in step S501, the control unit 30 moves the carriage 342 backward while moving the wider adjustment region H2 in step S503. 'Is selected and the pretreatment liquid 40 is ejected from the pretreatment liquid nozzle array LP2, and the nozzles N [C of the ink nozzle arrays LI1 to LI4 are applied to the portions where the pretreatment liquid 40 has landed in step S504. ], N [M], N [Y], and N [K] eject ink 41 of a necessary color to land on the medium 22b.

  According to the print control of the third embodiment, for the medium 22a having a high absorbency, the width W1 of the narrower adjustment region H1 ′ is selected and the carriage 342 is moved forward to perform preprocessing. The pretreatment liquid 40 is ejected from the liquid nozzle row LP1, and the ink 41 is ejected. As a result, the drying time of the pretreatment liquid 40 can be shortened as in the case 2 of FIG. 4, so that the ink 41 can be landed before the reaction component of the pretreatment liquid 40 penetrates too much into the medium 22 a. it can. Therefore, as in Case 2 of FIG. 5, the reactivity between the pretreatment liquid 40 and the ink 41 can be improved, and the print image quality can be improved.

  On the other hand, for the medium 22b having low absorbency, the width W1 of the wider adjustment region H2 ′ is selected and the pretreatment liquid 40 is ejected from the pretreatment liquid nozzle row LP2 while the carriage 342 is moved backward. Ink 41 is ejected. Thereby, since the drying time of the pretreatment liquid 40 can be lengthened as in the case 3 of FIG. 4, it is possible to promote the drying of the pretreatment liquid 40 remaining in the medium 22b. Therefore, since the position of the ink 41 that has landed on the medium 22b can be stabilized as in the case 3 of FIG. 5, the print image quality can be improved. As described above, according to the liquid jet head 36 of the third embodiment, the width of the adjustment region is selected according to the type of the medium 22, thereby changing the drying time of the pretreatment liquid 40. Since the degree of drying can be adjusted, the reactivity with the ink 41 can be improved regardless of the type of the medium 22, and the print image quality can be improved.

  In the configuration of FIG. 13, the case where either the width W1 of the adjustment region H1 ′ or the width W2 of the adjustment region H2 ′ is selected according to the type of the medium 22 is illustrated. Depending on the type, the width of the adjustment region itself may be changed. For example, the width W1 of the adjustment region H1 ′ can be changed by configuring the pretreatment liquid nozzle row LP1 to be movable in the positive and negative directions in the X direction. Further, by configuring the pretreatment liquid nozzle row LP2 to be movable in the positive and negative directions in the X direction, the width W2 of the adjustment region H2 ′ can also be changed. According to this, the adjustable widths W1 and W2 are stored in advance, and by selecting the widths W1 and W2 according to the type of the medium 22, the widths W1 and W2 are adjusted so that the widths W1 and W2 are obtained. It is possible to move the processing liquid nozzle rows LP1 and LP2 in the X direction. Therefore, even in such a configuration, the drying time of the pretreatment liquid 40 can be adjusted by selecting the width of the adjustment region according to the type of the medium 22. According to this configuration, since the width of the adjustment region itself can be changed according to the type of the medium 22, the drying time of the pretreatment liquid 40 can be adjusted more finely.

<Fourth embodiment>
A fourth embodiment of the present invention will be described. In the first to third embodiments, the liquid ejecting apparatus 10 including the serial head in which the carriage 342 on which the liquid ejecting head 36 is mounted moves in the X direction is illustrated. However, in the fourth embodiment, the conveyance direction of the medium 22 The liquid ejecting apparatus 10 including the liquid ejecting head 36 configured as a long line head in a direction intersecting with (here, the X direction) is illustrated.

  FIG. 15 is a partial configuration diagram of the liquid ejecting apparatus 10 according to the fourth embodiment of the invention. The liquid ejecting head 36 in the liquid ejecting apparatus 10 shown in FIG. 15 is a line head in which the pretreatment liquid nozzle array LP1 and the four nozzle arrays LI1 to LI4 are arranged in the Y direction at intervals. The pretreatment liquid nozzle row LP1 and the ink nozzle rows LI1 to LI4 are a set of a plurality of nozzles N arranged linearly along the X direction. Each of the pretreatment liquid nozzle row LP1 and the ink nozzle rows LI1 to LI4 may be a plurality of rows (for example, a staggered arrangement or a staggered arrangement).

  As shown in the enlarged view of FIG. 15, each of the ink nozzle rows LI1 to LI4 has different colors of ink 41, that is, four colors of cyan (C), magenta (M), yellow (Y), and black (K). It is composed of nozzles N [C], N [M], N [Y], and N [K] that eject color ink. The pretreatment liquid nozzle row LP1 includes a plurality of pretreatment liquid nozzles N [A] that eject the pretreatment liquid 40. The pretreatment liquid nozzle row LP1 is arranged on the negative side in the Y direction (upstream side in the transport direction of the medium 22) when viewed from the ink nozzle rows LI1 to LI4. Further, in the liquid jet head 36 of FIG. 15, the pretreatment liquid nozzle row LP1, the drying degree adjusting unit H1, and the ink nozzle rows LI1 to LI4 have overlapping portions in a side view from the Y direction (first direction). . In the liquid jet head 36 of FIG. 15, the range in which the nozzles of the pretreatment liquid nozzle row LP1 are distributed in the Y direction and the range in which the drying degree adjusting unit H1 extends are the nozzles N of the ink nozzle rows LI1 to LI4 in the Y direction. [C], N [M], N [Y], and N [K] overlap with each other in a plan view.

  On the ejection surface 360 of the liquid ejecting head 36, a drying degree adjusting unit H1 for adjusting the degree of drying of the pretreatment liquid 40 that has landed on the medium 22 is disposed. Specifically, the drying degree adjusting unit H1 is disposed between the ink nozzle rows LI1 to LI4 and the pretreatment liquid nozzle row LP1 so as to extend in a strip shape in the X direction. A drying mechanism Ht for accelerating the drying of the pretreatment liquid 40 that has landed on the medium 22 is disposed in the drying degree adjusting unit H1. The configuration of the drying mechanism Ht is the same as that of the first embodiment. The drying degree adjusting unit H1 may be provided with an adjustment nozzle row instead of the drying mechanism Ht as in the second embodiment, and the drying degree adjusting unit H1 as in the third embodiment. It may be an adjustment region in which the width in the Y direction can be changed. These points are the same in each modified example of the fourth embodiment described later.

  According to such a configuration of FIG. 15, whether or not the control unit 30 promotes the drying of the pretreatment liquid 40 that has landed on the medium 22 by turning on and off the drying mechanism Ht of the drying degree adjusting unit H1. Can be selected. Thereby, the drying degree of the pretreatment liquid 40 that has landed on the medium 22 can be adjusted. For example, when the pretreatment liquid 40 is ejected from the pretreatment liquid nozzle row LP1, by turning on the drying mechanism Ht of the drying degree adjusting unit H1, drying of the pretreatment liquid 40 that has landed on the medium 22 can be promoted. The ink 41 can be landed. By turning off the drying mechanism Ht of the drying degree adjusting unit H1, the ink 41 can be landed thereafter without promoting the drying of the pretreatment liquid 40 landed on the medium 22. Therefore, even if the liquid ejecting head 36 is a line head as shown in FIG. 15, the degree of drying of the pretreatment liquid 40 can be adjusted according to the type of the medium 22 as in the first embodiment.

(Modification of the fourth embodiment)
A liquid jet head 36 according to a modification of the fourth embodiment will be described. In the modification of the fourth embodiment, a line head that can not only land the pretreatment liquid 40 on the medium 22 before ink landing but also can land the posttreatment liquid 42 after ink landing is taken as an example. FIG. 16 is a plan view of the ejection surface 360 of the liquid ejection head 36 according to a modification of the fourth embodiment. The liquid jet head 36 of FIG. 16 differs from that of FIG. 15 in that a post-processing liquid nozzle row LP1 ″ is arranged on the positive side in the Y direction (downstream in the transport direction of the medium 22) of the drying degree adjusting unit H1. It is a point. The post-processing liquid nozzle row LP1 ″ is a set of a plurality of post-processing liquid nozzles N [B] arranged linearly along the X direction. The post-treatment liquid nozzle N [B] of the post-treatment liquid nozzle row LP1 ″ can eject the post-treatment liquid 42 supplied from the liquid container 24. In the liquid jet head 36 of FIG. 16, the pretreatment liquid nozzle row LP1, the drying degree adjustment unit H1, the ink nozzle rows LI1 to LI4, and the posttreatment liquid nozzle row LP1 ″ are in the Y direction (first direction). From the side view. In the liquid ejecting head 36 in FIG. 16, the range in which the post-processing liquid nozzle row LP1 ″ in the Y direction is distributed is the range in which the nozzles in the pre-processing liquid nozzle row LP1 are distributed in the Y direction. And the range in which the drying degree adjusting unit H1 extends and the range in which the nozzles N [C], N [M], N [Y], and N [K] of the ink nozzle rows LI1 to LI4 are distributed overlap in a plan view.

  According to the liquid ejecting head 36 of FIG. 16, while the pretreatment liquid 40 is ejected from the pretreatment liquid nozzle N [A] of the pretreatment liquid nozzle array LP1, the ink 41 is ejected from the ink nozzle arrays LI1 to LI4. The post-processing liquid 42 can also be ejected from the post-processing liquid nozzle N [B] of the post-processing liquid nozzle row LP1 ″. Then, the degree of drying of the pretreatment liquid 40 can be adjusted before ink landing by turning on or off the drying mechanism Ht of the degree-of-drying adjusting unit H 1 according to the type of the medium 22. Therefore, even if the liquid ejecting head 36 is a line head as shown in FIG. 16, the reactivity with the ink 41 can be improved regardless of the type of the medium 22, and the printing image quality can be improved. Further, as in the third modification of the first embodiment, after the ink has landed, the post-treatment liquid 42 can also be ejected, so that the image quality of the printed image is improved and the gloss and light resistance are also improved. Can do.

  In addition, the liquid ejecting head 36 of each embodiment described above functions as a liquid ejecting unit that ejects the ink 41 and also functions as a pretreatment liquid coating mechanism that coats the medium 22 with the pretreatment liquid 40. Specifically, in the liquid ejecting head 36, the components (including the nozzles of the ink nozzle rows LI1 to LI4) that eject the ink 41 function as the liquid ejecting unit and eject the pretreatment liquid 40 (front The processing liquid nozzle rows LP1, LP2, LP1 ′, and LP2 ′) function as a preprocessing liquid coating mechanism. Furthermore, the liquid ejecting head 36 of FIGS. 9, 10, and 16 also functions as a post-treatment liquid coating mechanism that coats the medium 22 with the post-treatment liquid 42. Specifically, components of the liquid ejecting head 36 that eject the post-treatment liquid 42 (including the post-treatment liquid nozzle rows LP1 ″ and LP2 ″) function as a post-treatment liquid coating mechanism.

  In addition, the liquid ejecting head 36 according to each embodiment is divided into a liquid ejecting head 36 including a nozzle that ejects the pretreatment liquid 40 and a liquid ejecting head 36 including a nozzle that ejects the ink 41. Each of the ejection heads 36 may be mounted on a separate carriage 342. As described above, by separating the carriages 342, it is possible to adjust the drying time of the pretreatment liquid 40 by changing the distance between the carriages 342.

<Modification>
Each embodiment illustrated above can be variously modified, for example, can be appropriately combined within a range not contradicting each other. Further, the following examples may be combined with each embodiment.

(1) The structure of the liquid jet head 36 is appropriately changed. For example, in each of the above-described embodiments, the piezoelectric liquid ejecting head 36 using a piezoelectric element that imparts mechanical vibration to the pressure chamber is exemplified, but a heating element that generates bubbles in the pressure chamber by heating is used. It is also possible to employ a thermal type liquid jet head. Further, the configuration of the plurality of nozzles N in the liquid ejecting head 36 is not limited to the illustrations of the above-described embodiments. For example, the pretreatment liquid nozzle row and the ink nozzle row may be configured separately. In each of the above-described embodiments, the case where two pretreatment liquids 40 are landed and stacked on the medium has been described. However, the present invention is not limited to this, and three or more pretreatment liquids 40 are landed. You may make it overlap.

(2) In each of the above-described embodiments, the case where the liquid ejecting head 36 functions as a pretreatment liquid coating mechanism that coats the medium 22 with the pretreatment liquid 40 is exemplified, but the present invention is not limited thereto, and the pretreatment is performed. The liquid coating mechanism may be provided separately from the liquid ejecting head 36. In this case, the pretreatment liquid coating mechanism may be configured by a spray mechanism that coats the medium 22 by spraying the pretreatment liquid 40. In this case, the drying degree adjusting unit Ht may be provided on either side of the pretreatment liquid coating mechanism and the liquid jet head 36. 9, 10, and 16 exemplify the case where the liquid ejecting head 36 functions as a post-treatment liquid coating mechanism that coats the medium 22 with the post-treatment liquid 42, the present invention is not limited thereto. The post-treatment liquid coating mechanism may also be provided separately from the liquid jet head 36. In this case, the post-treatment liquid coating mechanism may be configured by a spray mechanism that coats the medium 22 by spraying the post-treatment liquid.

(3) The liquid ejecting apparatus exemplified in each of the above-described embodiments can be employed in various apparatuses such as a facsimile apparatus and a copying machine in addition to apparatuses dedicated to printing. However, the use of the liquid ejecting apparatus of the present invention is not limited to printing. For example, a liquid ejecting apparatus that ejects a solution of a coloring material is used as a manufacturing apparatus that forms a color filter of a liquid crystal display device. Further, a liquid ejecting apparatus that ejects a solution of a conductive material is used as a manufacturing apparatus that forms wiring and electrodes of a wiring board.

DESCRIPTION OF SYMBOLS 10 ... Liquid ejecting apparatus, 22 ... Medium, 22a ... Highly absorbable medium, 22b ... Low absorbable medium, 24 ... Liquid container, 30 ... Control part, 301 ... ROM, 302 ... RAM, 303 ... Discrimination part, 32 ... transport mechanism, 322 ... supply roller, 324 ... discharge roller, 34 ... moving mechanism, 342 ... carriage, 344 ... transport belt, 36 ... liquid ejection head, 360 ... ejection surface, 37 ... medium sensor, 40 ... pretreatment liquid, DESCRIPTION OF SYMBOLS 41 ... Ink, 71 ... Flow path board | substrate, 712 ... Opening part, 714 ... Branching flow path, 716 ... Communication flow path, 72 ... Pressure chamber board | substrate, 722 ... Opening part, 73 ... Vibrating plate, 74 ... Piezoelectric element, 75 ... Support, 754... Introducing flow path, 76... Nozzle plate, H1, H2... Drying degree adjusting unit, Ht. , LI4 ... Ink nozzle , LP1, LP2, LP1 ', LP2' ... Pretreatment liquid nozzle row, LP1 '', LP2 '' ... Posttreatment liquid nozzle row, N [A] ... Pretreatment liquid nozzle, N [B] ... Posttreatment liquid nozzle , N [C], N [M], N [Y], N [K]... Ink nozzle, W1, W2... X direction width of the adjustment region, SC.

Claims (12)

A transport mechanism for transporting the medium in the first direction;
A pretreatment liquid coating mechanism for coating the medium with a pretreatment liquid;
A liquid ejecting section including an ink nozzle row for ejecting ink;
A controller for controlling the pretreatment liquid coating mechanism and the liquid ejecting unit;
A liquid ejecting apparatus comprising: a drying degree adjusting unit that adjusts a degree of drying of the pretreatment liquid coated on the medium between the ink nozzle row and the pretreatment liquid coating mechanism. The drying degree adjustment unit includes a drying mechanism that promotes drying of the pretreatment liquid,
A discriminating unit for discriminating the type of the medium,
The liquid ejecting apparatus according to claim 1, wherein the control unit selects whether to accelerate drying of the pretreatment liquid by the drying mechanism in accordance with the type of the medium determined by the determination unit. The drying degree adjustment unit includes an adjustment nozzle row that ejects the pretreatment liquid,
A discriminating unit for discriminating the type of the medium,
The control unit selects either the pretreatment liquid coating mechanism or the adjustment nozzle row according to the type of the medium determined by the determination unit and coats the medium with the pretreatment liquid. Item 2. The liquid ejecting apparatus according to Item 1. The drying degree adjustment unit includes an adjustment region having a width for adjusting a distance between the pretreatment liquid coating mechanism and the ink nozzle row,
A discriminating unit for discriminating the type of the medium,
The liquid ejecting apparatus according to claim 1, wherein the control unit selects a width of the adjustment region in accordance with the type of the medium determined by the determination unit. A liquid ejecting head comprising the pretreatment liquid coating mechanism and the liquid ejecting section;
A moving mechanism for reciprocating the liquid jet head in a second direction intersecting the first direction,
The pretreatment liquid coating mechanism and the ink nozzle row are each arranged along the first direction,
The drying degree adjusting unit extends in a strip shape in the first direction,
5. The liquid ejecting apparatus according to claim 1, wherein the pretreatment liquid coating mechanism, the drying degree adjusting unit, and the ink nozzle row have overlapping portions in a side view from the second direction. The liquid ejecting apparatus according to claim 5, wherein the pretreatment liquid coating mechanism and the drying degree adjusting unit are arranged on one side or both sides in the second direction of the ink nozzle row. A post-treatment liquid coating mechanism that coats the medium landed with the ink with a post-treatment liquid;
The liquid ejecting apparatus according to claim 5, wherein the post-processing liquid coating mechanism has a portion that overlaps with the ink nozzle in a side view from the second direction in the side view from the second direction. The liquid ejecting apparatus according to claim 7, wherein the pretreatment liquid coating mechanism overlaps the ink nozzle row in a side view from the second direction on the upstream side in the first direction than the posttreatment liquid coating mechanism. A liquid ejecting head including the pretreatment liquid coating mechanism and the liquid ejecting unit;
The liquid ejecting head is a line head that is long in a second direction intersecting the first direction,
The pretreatment liquid coating mechanism and the ink nozzle row are each arranged along the second direction,
The drying degree adjustment unit extends in a strip shape in the second direction,
The pretreatment liquid coating mechanism is disposed on the upstream side in the first direction when viewed from the ink nozzle row,
5. The liquid ejecting apparatus according to claim 1, wherein the pretreatment liquid coating mechanism has a portion that overlaps a nozzle of the ink nozzle row in a side view from the first direction. The liquid ejecting head includes a post-treatment liquid coating mechanism that ejects a post-treatment liquid onto the medium on which the ink has landed,
The post-treatment liquid coating mechanism is disposed on the downstream side in the first direction when viewed from the ink nozzle row,
The liquid ejecting apparatus according to claim 9, wherein the post-processing liquid coating mechanism includes a portion overlapping the ink nozzle row in a side view from the first direction. A liquid ejecting method for a liquid ejecting apparatus in which a medium is coated with a pretreatment liquid and then ink is landed on the medium,
The liquid ejecting apparatus includes: a transport mechanism that transports the medium in a first direction; a pretreatment liquid coating mechanism that coats the medium with the pretreatment liquid; and a liquid ejecting unit that includes an ink nozzle row that ejects the ink. A drying degree adjusting unit that adjusts a drying degree of the pretreatment liquid coated on the medium between the ink nozzle row and the pretreatment liquid coating mechanism, and the drying degree adjustment unit Is configured to include a drying mechanism that promotes drying of the pretreatment liquid,
A liquid ejecting method for determining a type of the medium and selecting whether or not to promote drying of the pretreatment liquid by the drying mechanism according to the determined type of the medium. A liquid ejecting method for a liquid ejecting apparatus in which a medium is coated with a pretreatment liquid and then ink is landed on the medium,
The liquid ejecting apparatus includes: a transport mechanism that transports the medium in a first direction; a pretreatment liquid coating mechanism that coats the medium with the pretreatment liquid; and a liquid ejecting unit that includes an ink nozzle row that ejects the ink. A drying degree adjusting unit that adjusts a drying degree of the pretreatment liquid coated on the medium between the ink nozzle row and the pretreatment liquid coating mechanism, and the drying degree adjustment unit Is configured to include a drying mechanism that promotes drying of the pretreatment liquid,
Liquid ejection for discriminating the type of the medium, and selecting either the pretreatment liquid coating mechanism or the adjustment nozzle row according to the identified type of the medium to coat the medium with the pretreatment liquid Method.

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