JP2019059023A - Pre-processing device, inkjet system, and pre-processing method - Google Patents

Abstract

To allow for execution of image formation with excellent quality by controlling a behavior of a droplet that is discharged from an inkjet device.SOLUTION: A pre-processing device includes: a surface characteristic measurement part for measuring surface characteristic of a medium; a pre-processing execution part for performing pre-processing to the medium; and a pre-processing control part for controlling an execution mode of the pre-processing for each position of the medium based on the surface characteristic.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a pretreatment apparatus, an inkjet system, and a pretreatment method.

  As one aspect of an apparatus used for outputting digitized information, a printer employing an inkjet method (hereinafter, referred to as an "inkjet apparatus") is known. In image forming output, which is one aspect of information output in an inkjet apparatus, ink used for forming an image is ejected from a recording head and attached to a medium (for example, paper) on which an image is formed.

  Forming an image by setting ink dots forming an image to a predetermined size by controlling the amount of ink deposited on the medium, and depositing the ink dots on the medium in a two-dimensional direction. it can.

  In the image formation output using the ink jet method, it is possible to delicately express the gradation and gradation of the image by adjusting the size of ink dots and adjusting the arrangement to be coarse and dense.

  However, the inkjet method has a problem that causes the quality of the image formed on the medium to be degraded. That is, depending on the speed at which the ink spreads, the ink attached to the medium flows on the medium, or the ink spreads on the medium to cause a beading phenomenon in which the dots of the ink are connected, or Bleeding or the like occurs when ink dots bleed. Such a phenomenon reduces the quality of the image formed on the medium.

  On the other hand, a technique for applying a pretreatment agent to the medium before discharging the ink, changing the viscosity of the discharged ink, and controlling the speed at which the ink spreads on the medium, that is, the behavior of the ink on the medium Are disclosed (see, for example, Patent Document 1).

  According to Patent Document 1, pre-processing according to the type of medium is uniformly performed on one side of the medium. Therefore, even if the technology disclosed in Patent Document 1 is applied, the behavior of the ink with respect to the medium can not be controlled because the shape of the surface of the medium differs depending on the position on the medium, and Image quality is degraded.

  The present invention has been made in consideration of the above-described circumstances, and has an object of controlling the behavior of droplets ejected from an inkjet apparatus to enable execution of high-quality image formation.

  In order to solve the above problems, one aspect of the present invention is a surface property measurement unit that measures a surface property of a medium, a pretreatment execution unit that performs pretreatment on the medium, and the position of the medium based on the surface property. And a pre-processing execution control unit that controls an execution mode of the pre-processing in each unit.

  According to the present invention, it is possible to control the behavior of droplets ejected from the ink jet apparatus, and to make it possible to perform high-quality image formation.

Explanatory drawing explaining the fluidity | liquidity of a droplet. The figure which shows the dispersion state of the pigment particle to a solvent. FIG. 6 is a view showing a measurement image obtained by measuring the shape of the surface of the recording medium. FIG. 2 is a view showing a cross section of a recording medium. BRIEF DESCRIPTION OF THE DRAWINGS The figure which shows the outline of the inkjet system which concerns on the 1st Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS The block diagram of the discharge head which discharges the droplet which concerns on the 1st Embodiment of this invention. FIG. 1 is a cross-sectional view showing a schematic configuration of a colorant discharge head according to a first embodiment of the present invention. FIG. 2 is a view showing an operation mode of the ink jet system according to the present embodiment according to the first embodiment of the present invention. The figure which shows the hardware constitutions of DFE which concerns on the 1st Embodiment of this invention. BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows the function structure of the inkjet apparatus which concerns on the 1st Embodiment of this invention, and a pre-processing apparatus. FIG. 2 is a block diagram showing a functional configuration of the DFE according to the first embodiment of the present invention. FIG. 2 is a block diagram showing a functional configuration of a main control unit according to the first embodiment of the present invention. FIG. 3 is a diagram showing the configuration of a characteristic information data table according to the first embodiment of the present invention. FIG. 3 is a diagram showing the configuration of a characteristic information data table according to the first embodiment of the present invention. FIG. 3 is a diagram showing the configuration of a characteristic information data table according to the first embodiment of the present invention. FIG. 6 is a view showing a relationship between gray values of a measurement image of the surface of the recording medium according to the first embodiment of the present invention and surface characteristics. FIG. 6 is a view showing a relationship between gray values of a measurement image of the surface of the recording medium according to the first embodiment of the present invention and surface characteristics. The figure which shows the formation aspect of the pre-processing agent layer which concerns on the 1st Embodiment of this invention. The figure which shows the formation aspect of the pre-processing agent layer which concerns on the 1st Embodiment of this invention. FIG. 2 is a view showing a droplet discharge mode according to the first embodiment of the present invention. The flowchart which shows the flow of the process which calculates the quantity of the pre-processing agent which concerns on the 1st Embodiment of this invention. The figure which shows the outline of the inkjet system which concerns on the 2nd Embodiment of this invention. FIG. 5 is a perspective view of an image forming apparatus according to a second embodiment of the present invention. FIG. 5 is a perspective view of an image forming apparatus according to a second embodiment of the present invention. FIG. 5 is a block diagram showing the functional arrangement of an image forming apparatus according to the second embodiment of the present invention; FIG. 10 is a sequence diagram showing a flow of processing for performing image formation output according to a second embodiment of the present invention. The figure which shows the function structure of the main-control part which concerns on the 3rd Embodiment of this invention. The flowchart which shows the flow of the feedback control which concerns on the 3rd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiment described below, an ink, which is an example of the image forming agent according to the present invention, is discharged onto a printing sheet, which is an example of a medium, to form an image, which is an example of an image forming object. First, the fluidity of the ink droplet will be described as an example of the behavior of the ink droplet discharged onto the recording medium such as printing paper.

  FIGS. 1A to 1C are explanatory diagrams for explaining the fluidity of a droplet LD, which is an ink droplet containing a colorant such as a pigment, to the recording medium M. FIG. FIG. 1A is a view showing a state immediately before the droplet LD is discharged and contacts the recording medium M which is a printing sheet. As shown in FIG. 1A, the droplet LD consists of pigment particles P and a solvent L.

  Further, on the surface of the recording medium M, an aggregating agent AG is applied which is a processing agent (reactant) for aggregating the pigment particles P by changing the dispersion state of the pigment particles P. The process of applying the coagulant AG to the surface of the recording medium M is referred to as "pretreatment". The pretreatment is performed in advance before discharging the droplet LD. By this pretreatment, a pretreatment agent layer PC is formed on the surface of the recording medium M which is the discharge destination of the droplet LD.

  FIG. 1A is a view showing the dispersion state of pigment particles P with respect to the solvent L immediately before the droplet LD contacts the recording medium M. As shown in FIG. As shown in FIG. 1A, the droplets LD are formed in a state in which the pigment particles P are dispersed in the solvent L. In the case of a pigment ink containing a pigment as a colorant, pigment particles P are uniformly dispersed and present in a solvent L such as a solvent or a resin.

  FIG. 1B is a view showing the dispersion state of the pigment particles P with respect to the solvent L at the moment when the droplet LD adheres to the recording medium M. When the droplets LD adhere to the recording medium M, the pigment particles P aggregate due to the aggregating agent AG contained in the pretreatment agent layer PC, and the dispersion state of the pigment particles P with respect to the solvent L is not uniform.

  FIG. 2 illustrates the dispersion state of the pigment particles P in the droplet LD with respect to the solvent L. In the following description, the droplet LD before being attached to the recording medium M is in the state as shown in FIG. 2A, that is, the pigment particles P are uniformly dispersed in the solvent L. Assume that FIG. 2B exemplifies a state in which the distribution of pigment particles P is nonuniform relative to the solvent L due to the effect of the pretreatment agent layer PC formed on the recording medium M.

  As shown in FIG. 2A, when the size of the pigment particles P dispersed uniformly in the solvent L is a particle diameter r, the pigment particles P distributed uniformly in the solvent L However, as shown in FIG. 2 (b), when the particles are agglomerated with each other, the apparent particle size of the pigment particles P increases from the particle diameter r to the particle diameter r '. In addition, due to the aggregation of the pigment particles P, the dispersed state of the pigment particles P with respect to the solvent L is not uniform.

  At this time, the diffusion coefficient D, which is a coefficient when the pigment particles P dispersed in the solvent L move, is proportional to the absolute temperature T according to the Stokes-Einstein equation shown in Equation 1, and It is inversely proportional to the size. The Stokes-Einstein equation is an equation representing the diffusion state of the pigment particles P dispersed in the solvent L based on the relationship between the viscosity η of the solvent L and the diffusion coefficient D.

In Formula 1, D is a diffusion coefficient, η is the viscosity of the solvent L, T is an absolute temperature, k _B is a Boltzmann constant, and a is a particle radius. As shown in Formula 1, as the size of the pigment particle P increases, the diffusion coefficient D decreases and the freedom of movement of the pigment particle P with respect to the solvent L decreases. Therefore, when the pigment particles P aggregate, the droplets LD are less likely to flow.

  Generally, the droplets LD attached to the recording medium M flow and spread toward the periphery of the attached portion. Therefore, when the droplets LD adhere to the recording medium M, the droplets LD contact the recording medium M The size of the droplet LD becomes larger than the moment. However, as described above, when the droplets LD become difficult to flow due to the aggregation of the pigment particles P, the size of the droplets LD adhering to the recording medium M also becomes difficult to change, and the liquid when adhering on the recording medium M The size of the droplet LD is smaller than when the droplet LD is easy to flow. FIG. 1C is a diagram showing how the droplet LD penetrates into the recording medium M.

  As shown in FIG. 1C, when the recording medium M is a permeable medium such as plain paper, the droplet LD penetrates into the pretreatment agent layer PC and the recording medium M, and the pigment particle P is a recording medium. It adheres to the surface of M. Then, the fixed droplets LD are dried to form dots of the pigment particles P.

  FIG. 3 is a diagram showing an example of measurement values obtained by measuring the surface of the recording medium M. As shown in FIG. In FIG. 3, the measurement values of the shape of the surface of the recording medium M are represented by a gray-scale image. The difference in density occurs due to, for example, the difference in structure near the surface of the recording medium M, the deviation of the material of the recording medium M, or the like.

  Such a difference in structure near the surface of the recording medium M, deviation of materials, and the like are called surface characteristics of the recording medium M. Here, the surface characteristics of the recording medium M will be described in detail. FIG. 4A shows a cross section of the recording medium M whose surface is horizontal, and FIG. 4B shows a cross section of the recording medium M having irregularities on the surface.

  As shown in FIG. 4B, when the surface of the recording medium M has fine irregularities, the contact angle with the surface of the recording medium M changes even if the concentration of the coagulant agent AGC is uniform on the surface of the recording medium M. . At this time, as an example showing the speed at which the droplet LD wets and spreads on the recording medium M, that is, the difference in the behavior of the droplet LD on the recording medium M, the recording medium depends on the contact angle of the droplet LD on the surface of the recording medium M It is possible to evaluate the wettability which is an index indicating the adhesion state of the droplet LD to M.

  For example, the smaller the contact angle of the droplet LD with the recording medium M, the better the wettability is evaluated. The better the wettability, the larger the contact area between the droplet LD and the recording medium M, and the faster the wetting and spreading of the droplet LD on the recording medium M becomes. On the other hand, the lower the wettability, the smaller the contact area between the droplet LD and the recording medium M, and the slower the wetting and spreading of the droplet LD on the recording medium M becomes.

  With respect to the recording medium M shown in FIG. 4A, the wettability of the droplet LD is uniform to the surface of the recording medium M. In such a case, the droplet LD adheres to the recording medium M by forming a spherical cap shape. On the other hand, as shown in FIG. 4B, when the droplet LD contacts the recording medium M having irregularities on the surface, the area where the droplet LD contacts the recording medium M is small, and the recording medium M Since the contact angle of the droplet LD becomes large, the wettability of the droplet LD becomes worse.

  Thus, the area of the droplet LD in contact with the recording medium M also changes depending on the degree of unevenness of the recording medium M. Therefore, if the surface characteristics of the recording medium M are not uniform, the behavior of the droplet LD with respect to the recording medium M also changes and becomes nonuniform. Therefore, if the shape of the dots formed on the recording medium M is uniform It disappears.

  Furthermore, the coagulant concentration AGC in the pretreatment agent layer PC influences the contact angle of the droplet LD with the recording medium M, the speed at which the coagulant AG diffuses into the solvent L of the droplet LD, and the like. Therefore, the contact area between the droplet LD and the recording medium M changes also by the coagulant concentration AGC of the pretreatment agent layer PC, so the behavior of the droplet LD with respect to the recording medium M changes.

  Such a change in the behavior of the droplet LD with respect to the recording medium M may degrade the quality (image quality) of the image formed on the recording medium M by discharging the droplet LD. For example, when dots of pigment particles P having a uniform shape can not be formed because the surface characteristics of the recording medium M are not uniform, density unevenness or the like occurs in the formed image and the image quality is degraded. .

  Therefore, in the present invention, the behavior of the droplet LD discharged to the recording medium M is controlled. At this time, the pretreatment of the recording medium M to be performed to control the behavior of the droplet LD is performed based on the surface characteristics of the recording medium M, so that the droplet LD which is constant regardless of the position of the recording medium M Make it possible to control the behavior. It is the gist of the present invention to make it possible to execute imaging output of higher quality by this.

Embodiment 1
In the present embodiment, a line head type inkjet apparatus will be described as an example, which transports a recording medium and executes an image formation output by droplets discharged from a fixed ejection head.

  FIG. 5 is a diagram showing an outline of the inkjet system 4 according to the present embodiment. As shown in FIG. 5, the inkjet system 4 according to the present embodiment transports the DFE (Digital Front End) 1, the inkjet device 2, the pretreatment device 3, the measuring devices 5 A and 5 B, and the roll paper Md that is the recording medium M. A carry-in unit 17, a drying unit 30, and a carry-out unit 60 disposed along the direction Xm are provided.

  The DFE 1 transmits instruction information to each unit constituting the inkjet system 4 to control the operation thereof to execute image formation output. Therefore, DFE 1 functions as an image formation output control device. Further, the DFE 1 executes raster image processor (RIP) processing based on information of an image to be an image forming output, and generates raster data.

  The DFE 1 causes the inkjet device 2 and the preprocessing device 3 to execute image formation output using raster data, bitmap data input to the DFE 1, and the like. Therefore, the bitmap data input to the DFE 1 and the raster data generated by the DFE 1 correspond to drawing information to be referred to by the inkjet device 2 and the preprocessing device 3 when executing image formation output. The drawing information is a part of image forming information that controls the operation of the preprocessing device 3 and controls the operation of the inkjet device 2 as described later.

  The inkjet device 2 has four colorant discharge heads 21K, 21C, 21M, and 21Y for black (K), cyan (C), magenta (M), and yellow (Y) (hereinafter referred to as "colorant discharge heads 21". A droplet discharge device including the In the following description, it is assumed that the color of the droplet LD discharged from the colorant discharge head 21 is indicated using the symbol shown in the parenthesis.

  Further, in the present embodiment, a colored droplet such as ink containing pigment particles P as a coloring agent will be described as the droplet LD. Therefore, the colorant discharge head 21 functions as a colored droplet discharge unit.

  The pretreatment device 3 is a droplet ejection device including pretreatment agent ejection heads 31H and 31L, which are pretreatment units that eject a coagulant AG having a characteristic of changing the dispersion state of the pigment particles P. The pretreatment agent ejection head 31H is an ejection head which ejects the pretreatment agent AGH as a droplet LD (first processed droplet) having a high concentration of the coagulant AG, and functions as a first droplet ejection portion.

  The pretreatment agent ejection head 31L is an ejection head which ejects the pretreatment agent AGL as a droplet LD (second treated droplet) having a low concentration of the coagulant AG, and functions as a second droplet ejection portion. The pretreatment agent ejection heads 31H and 31L function as a treatment droplet ejection unit that ejects the pretreatment agent AGL as treatment droplets.

  In the present embodiment, the recording medium M is continuous paper (hereinafter referred to as “roll paper Md”) wound in a roll shape. As the recording medium M, for example, continuous paper such as continuous paper or continuous form paper in which perforations are formed at predetermined intervals may be used, instead of being wound in a roll shape. Further, the recording medium M may be a cut sheet cut into a predetermined size. Furthermore, it may be a film instead of paper.

  The measuring devices 5A and 5B are line sensors that continuously acquire one-dimensional images of the roll paper Md in a direction perpendicular to the conveyance direction Xm of the roll paper Md, that is, in the width direction of the roll paper Md. The measuring devices 5A and 5B may be an area sensor that acquires a two-dimensional image of the roll paper Md, or an imaging device such as a camera.

  The measuring devices 5A and 5B measure, for example, a predetermined range (hereinafter referred to as "one band") of the roll paper Md, and generate a measurement image as shown in FIG. 3 based on the measured values. Note that the measurement image is generated at a quality that is at least greater than the resolution of the image to be formed and output. The predetermined range to be measured may be, for example, the minimum unit capable of controlling the process performed by the preprocessing device 3 in the predetermined range.

  In addition, the measuring devices 5A and 5B can be configured by a plurality of line sensors or area sensors, the amount of measurement per sensor can be reduced, and the measurement speed can be improved. The measuring device 5A is disposed upstream of the preprocessing device 3 with respect to the transport direction Xm, measures the recording medium M before the image formation output is performed, and generates a measurement image before output which is measurement information before output.

  The measuring device 5B is disposed downstream of the inkjet device 2 in the transport direction Xm, measures the recording medium M after the image formation output is performed, and generates an output measurement image which is measurement information after output. Therefore, the measuring device 5A functions as a surface property measuring unit that measures the surface property of the roll paper Md before the droplet LD is discharged. Further, the measuring device 5B measures the roll paper Md on which the dots of the pigment particles P are formed by the droplets LD.

  The carry-in unit 17 includes a paper feed unit 18 and a plurality of carry-in side conveyance rollers 19, and uses the carry-in side conveyance roller 19 to carry the roll paper Md in the paper feed unit 18 into the preprocessing device 3. The pretreatment device 3 discharges the droplets LD containing the coagulant AG onto the roll paper Md conveyed from the carry-in unit 17 to form the pretreatment agent layer PC on the surface of the roll paper Md.

  The inkjet device 2 discharges droplets containing a pigment or a dye as a colorant on the roll paper Md on which the pretreatment agent layer PC is formed, and forms an image on the surface of the roll paper Md. The drying unit 30 dries the roll paper Md on which the image is formed, for example, by heating. The discharge unit 60 discharges the roll paper Md on which the image is formed, and uses the discharge side conveyance roller 62 to wind the roll paper Md on which the image is formed on the storage unit 61.

  When the roll paper Md is wound around the storage roll of the storage unit 61, storage is performed so that another image is not transferred to the back surface of the roll paper Md if the pressure acting on the roll paper Md becomes large. A drying mechanism may be provided to dry the roll paper Md immediately before winding by the section 61.

  As described above, the inkjet system 4 according to the present embodiment conveys the roll paper Md to the pretreatment device 3 and the inkjet device 2 by the loading unit 17 and forms an image on the surface of the roll paper Md. Then, the roll paper Md on which the image is formed is dried by the drying unit 30 and taken up by the discharge unit 60 so that the paper can be discharged to the outside of the inkjet system 4.

  Next, with reference to FIG. 6, the configuration of a discharge head that discharges a droplet LD according to the present embodiment will be described. As shown in FIG. 6, the inkjet system 4 includes the pretreatment agent discharge heads 31H and 31L, and the colorant discharge heads 21K, 21C, 21M and 21Y.

  The pretreatment agent ejection heads 31H and 31L are disposed upstream of the roll paper Md in the conveyance direction Xm, and the colorant ejection heads 21K, 21C, 21M and 21Y are disposed downstream of the pretreatment agent ejection heads 31H and 31L. ing.

  That is, while conveying the roll paper Md as a type of medium which is an object to form an image, the inkjet system 4 adheres a processing agent to perform pretreatment on the image formation position on the upstream side of the conveyance direction Xm. Let An area in which the processing agent adheres to the roll paper Md is a processing area, and a coloring agent is adhered to the processing area to form an image (image).

  In the present embodiment, the arrangement order of K, C, M, and Y is illustrated as the configuration of the ejection head, but the invention is not limited thereto. For example, the arrangement order of colors is Y, M, C , May be K. The combination of colors is not limited to K, C, M, and Y, and may be three colors such as green (G), red (R), and light cyan (LC). Also, the combination of colors may not be a combination but one black (K) color.

  The colorant discharge head 21K is a roll paper for the first head 21K-1, the second head 21K-2, the third head 21K-3, and the fourth head 21K-4 in the black (K) colorant discharge head 21K. They are arranged in a staggered manner in the direction orthogonal to the conveyance direction Xm of Md.

  In the inkjet apparatus 2, an image is formed on the recording medium M by arranging the first head 21K-1, the second head 21K-2, the third head 21K-3, and the fourth head 21K-4 in a staggered manner. The image formation can be performed in the width direction of the area to be cut, that is, in the area orthogonal to the transport direction Xm of the roll paper Md.

  The colorant ejection heads 21 for each of the colors K, C, M, and Y, and the ejection heads for the pretreatment agent ejection heads 31H and 31L have the same configuration as the colorant ejection head 21K for black (K). , Duplicate explanations are omitted.

  FIG. 7 is a cross-sectional view showing a schematic configuration of the colorant discharge head 21K. The colorant discharge head 21 </ b> K includes a flow path plate 41, a diaphragm 42, a nozzle plate 43, a frame member 44, and a pressure generator 45. The flow path plate 41 forms a passage for the droplets LD to be discharged. The flow path plate 41 is made of, for example, a single crystal silicon substrate with a crystal plane orientation (110).

  The flow passage plate 41 forms the nozzle communication passage 40R and the liquid chamber 40F by performing anisotropic etching with an alkaline etching solution such as a potassium hydroxide (KOH) aqueous solution. The material that can be used for the flow path plate 41 is not limited to a single crystal silicon substrate. For example, as a material of the flow path plate 41, stainless steel, photosensitive resin, and other materials may be used.

  The diaphragm 42 is made of, for example, a metal plate processed by nickel electroforming (for example, an electroforming method, an electroforming method, etc.). The diaphragm 42 may be a metal plate other than nickel, or a bonding member between a metal and a resin plate. The diaphragm 42 is joined to the lower surface of the flow path plate 41, that is, in the inside direction of the colorant discharge head 21K. The diaphragm 42 is deformed by the pressure generation unit 45 applying a force.

  The nozzle plate 43 is made of, for example, a single crystal silicon substrate. The nozzle plate 43 is processed by anisotropic etching similarly to the flow path plate 41. The nozzle plate 43 may have a configuration in which a water repellent layer is formed on the outer surface of a metal member via a required layer. The nozzle plate 43 is joined to the upper surface of the flow path plate 41, that is, to the outside of the colorant discharge head 21K.

  In addition, the nozzle plate 43 has a plurality of nozzles 40N that discharge the droplets LD. Specifically, nozzles 40 N having a diameter of 10 to 30 μm are formed in the nozzle plate 43 corresponding to the respective liquid chambers 40 F.

  The frame member 44 is made of thermosetting resin such as epoxy resin or polyphenylene sulfite (PPS). Besides, a resin having similar characteristics may be used as a material of the frame member 44. The frame member 44 includes a housing portion 44I for housing the pressure generating portion 45, a concave portion serving as the common liquid chamber 40CR, and an ink supply port 40IN for supplying ink from the outside of the discharge head to the common liquid chamber 40CR. It is done. The frame member 44 holds the peripheral portion of the diaphragm 42.

  The pressure generating portion 45 has a piezoelectric element 45P, a base substrate 45B for bonding and fixing the piezoelectric element 45P, and a support portion disposed in the gap between the adjacent piezoelectric elements 45P. Further, an FPC (Flexible Printed Circuits) cable 45C for connecting the piezoelectric element 45P to a drive circuit is connected to the pressure generating unit 45.

  As the piezoelectric element 45P, for example, a laminated piezoelectric element (PZT) in which a piezoelectric material and an internal electrode are alternately laminated is used. The internal electrode has a plurality of individual electrodes and a plurality of common electrodes, and the individual electrodes or the common electrodes are alternately connected to the end face of the piezoelectric element 45P.

  The piezoelectric direction of the piezoelectric element 45P is, for example, a direction in which the crystal lengthens (hereinafter referred to as "d33 mode") when an electric field is applied parallel to the polarization direction to the crystal of the piezoelectric element 45P. The pressure generating unit 45 pressurizes or depressurizes the ink in the liquid chamber 40F using the piezoelectric effect in the d33 mode of the piezoelectric element 45P.

  When the piezoelectric element 45P applies an electric field parallel to the polarization direction to the crystal of the piezoelectric element 45P, the ink in the liquid chamber 40F is added to the d31 mode, which is the direction in which the crystal becomes shorter. The pressure may be reduced or reduced. Further, the pressure generating unit 45 may arrange one row of piezoelectric elements for one nozzle 40N which is an ink discharge port.

  The support portion may be formed simultaneously with the piezoelectric element 45P by dividing the piezoelectric element 45P which is a piezoelectric element member. That is, the discharge head 40K may be used as a support including the piezoelectric element 45P to which no voltage is applied. The colorant ejection heads 21 for each of the colors K, C, M, and Y, and the ejection heads for the pretreatment agent ejection heads 31H and 31L have the same configuration as the colorant ejection head 21K for black (K). , Duplicate explanations are omitted.

  Next, a pulling operation or a pushing operation, which is an operation in which the colorant discharge head 21K discharges the droplet LD from the nozzle 40N, will be specifically described. FIG. 8 is a view showing an operation mode of the inkjet system 4 according to the present embodiment.

  As shown in FIG. 8, the DFE 1 instructs the respective units constituting the inkjet system 4 to operate and controls the operation. Then, the pretreatment device 3 executes pretreatment for discharging the pretreatment agent PCA on the roll paper Md. In addition, the inkjet device 2 discharges the droplet LD containing a colorant onto the pre-processed roll paper Md to form an image.

  The measuring devices 5A and 5B each measure the roll paper Md, and generate a measurement image based on the measured value. The DFE 1 and the inkjet device 2, the DFE 1 and the preprocessing device 3, and the DFE 1 and the measuring devices 5A and 5B are communicably connected by signal lines 70LC, 71LC, 50ALC, and 50BLC, respectively.

  The print control unit 20Cc illustrated in FIG. 8 reduces the voltage applied to the piezoelectric element 45P from the reference potential and reduces the piezoelectric element 45P in the stacking direction thereof, thereby bending and deforming the diaphragm. Then, the volume of the liquid chamber 40F is increased by the bending deformation of the diaphragm 42. Thereby, the droplet LD flows into the liquid chamber 40F from the common liquid chamber 40CR.

  Next, the print control unit 20Cc raises the voltage applied to the piezoelectric element 45P and stretches the piezoelectric element 45P in the stacking direction to deform the diaphragm 42 in the nozzle 40N direction. Then, the deformation of the diaphragm 42 reduces the volume of the liquid chamber 40F. As a result, pressure is applied to the droplets LD in the liquid chamber 40F, and the droplets LD are discharged from the nozzle 40N.

  Thereafter, the print control unit 20Cc returns the voltage applied to the piezoelectric element 45P to the reference potential and restores the diaphragm 42 to the position before the reference voltage is lowered, that is, the initial position. In the colorant discharge head 21K, the liquid chamber 40F is depressurized by the expansion of the liquid chamber 40F, and the droplet LD is filled from the common liquid chamber 40CR into the liquid chamber 40F. Then, the vibration of the meniscus of the nozzle 40N is attenuated, and then the discharge operation of the next droplet LD is started. Thus, the operation of discharging the droplet LD is repeated.

  The driving method of the colorant discharge head 21K is not limited to pulling or pushing, and by controlling the voltage applied to the piezoelectric element 45P (hereinafter, referred to as "driving waveform"), pulling or pushing is performed. It is possible to hit and the like. The ejection heads of the colorant ejection heads 21 for the respective colors K, C, M, and Y have the same configuration as that of the colorant ejection head 21 K for black (K), and therefore redundant description will be omitted.

  Further, with regard to the pretreatment agent discharge heads 31H and 31L, the pretreatment control unit 30Cc included in the precoat controller 30C shown in FIG. 8 performs the same operation as the printing control unit 20Cc, and applies the droplet LD to the roll paper Md. The pretreatment is performed by discharging the

  In addition, the pressure generation part 45 in this embodiment is not limited to the piezoelectric element 45P, For example, well-known techniques, such as a thermal type and an electrostatic type, are also employable. The thermal type is a method of generating air bubbles by heating the droplet LD in the liquid chamber 40F using a heating resistor. The electrostatic type is a method in which the diaphragm and the electrode are disposed to face the wall surface of the liquid chamber 40F, and the diaphragm is deformed by generating an electrostatic force between the diaphragm and the electrode.

  The inkjet system 4 according to the present embodiment uses the colorant discharge heads 21K, 21C, 21M, and 21Y and the pretreatment agent discharge heads 31H and 31L in the width direction of the area where the image is formed on the roll paper Md. A full color image or a monochrome image can be formed over the entire area.

  Next, the hardware configuration of the DFE 1 according to the present embodiment will be described. As shown in FIG. 9, the DFE 1 includes a central processing unit (CPU) 11, a read only memory (ROM) 12, and a random access memory (RAM) 13. The DFE 1 further includes an HDD (Hard Disk Drive) 14 and an I / F 15. Devices such as the CPU 11 constituting the DFE 1 are connected to one another by a bus 16.

  The inkjet device 2, the pre-processing device 3, and the measuring devices 5 A and 5 B are also configured by the same hardware as the DFE 1. When the measuring devices 5A and 5B are imaging devices such as cameras, in addition to the configuration shown in FIG. 9, an imaging unit such as a camera may be included, and the measuring devices 5A and 5B may be infrared rays or ultrasonic waves. It may be configured to include a sensor that measures the surface of the roll paper Md by the like.

  The CPU 11 controls the overall operation of the DFE 1. The CPU 11 loads the program stored in the ROM 12 or the HDD 14 into the RAM 13 and executes the program to control the operation of the DFE 1. Control programs for controlling the CPU 11 are stored in the ROM 12 and the HDD 14. The RAM 13 is used as a work area for developing a program operated by the CPU 11 or intermediate data.

  The I / F 15 is used for communication between the DFE 1 and an external device such as a host device, and performs communication corresponding to a protocol such as TCP / IP (Transmission Control Protocol / Internet Protocol).

  Also, the I / F 15 may be configured to communicate by, for example, PCI Express (Peripheral Component Interconnect Bus Express), ISA (Industry Standard Architecture), or the like. Also, the I / F 15 may be configured to have a plurality of channels corresponding to each color of the print image data.

  The DFE 1 receives print job data transmitted from an external device such as a host device under the control of the CPU 11 via the I / F 15 and stores the data in the HDD 14. The DFE 1 generates raster data, which is image information such as bit map data corresponding to each color of CMYK, based on job data received from a host device such as a PC (Personal Computer), and includes information including raster data (hereinafter referred to as Send “print output data” to the inkjet device 2. The inkjet device 2 discharges the droplet LD to the roll paper Md based on the print output data.

  Further, the DFE 1 generates data (hereinafter referred to as “control information data”) for controlling the printing operation based on the print job data and the information input from the host device. The control information data includes the print mode, print type, feed / discharge information, print surface order, print sheet size, data size of print image data, resolution, paper type information, tone, color information, and information on the number of pages to be printed. Includes data on printing conditions such as

  Furthermore, data relating to the discharge of the post-processing liquid discharged by the post-processing device may be included as the control information data. The print output data is transmitted from the DFE 1 to the inkjet device 2 and the preprocessing device 3 respectively.

  Further, the DFE 1 sends data relating to the discharge of the droplet LD discharged by the preprocessing device 3 based on the pre-output measurement image generated by the measuring device 5A (hereinafter referred to as “preprocessing output data”) to the preprocessing device 3. Send.

  Furthermore, the DFE 1 analyzes the measurement image generated by the measurement device 5B to determine whether or not the desired dot is formed, and changes the discharge amount of the droplet LD in the pretreatment output data based on the determination result. And transmit to the preprocessing device 3.

  FIG. 10 is a block diagram showing functional configurations of the inkjet apparatus 2 and the pretreatment apparatus 3 according to the present embodiment. The inkjet device 2 controls an operation of forming an image on the roll paper Md based on print output data and control information data input from the DFE 1. The inkjet device 2 includes a printer controller 20C and a printer engine 20E.

  The printer controller 20C includes a CPU 20Cp and a print control unit 20Cc. The CPU 20Cp and the print control unit 20Cc are connected by a bus 20Cb so as to be able to transmit and receive. The bus 20Cb is connected to the signal line 70LC via the communication I / F. The CPU 20Cp controls the overall operation of the inkjet apparatus 2 using a control program stored in the ROM.

  The print control unit 20Cc transmits and receives information such as commands, parameters, and data to and from the printer engine 20E based on the control information data transmitted from the DFE 1. The print control unit 20Cc controls the printer engine 20E by transmitting and receiving information to and from the printer engine 20E.

  The printer controller 20C controls the printer engine 20E. The printer controller 20C transmits and receives control information data and the like to and from the DFE 1 through the signal line 20LC. The printer controller 20C transmits and receives control information data and the like to and from the printer engine 20E described later via the signal line 20LC.

  The printer controller 20C writes printing conditions and the like included in the transmitted and received control information data to the register of the printing control unit 20Cc, and stores the printing conditions in the register. The printer controller 20C controls the printer engine 20E based on the control information data to execute printing according to the print job data and the control information data.

  The printer engine 20E includes discharge control units 20EiC, 20EiM, 20EiY, and 20EiK. The ejection control units 20EiC, 20EiM, 20EiY, and 20EiK respectively eject droplets LD onto the roll paper Md based on the print output data transmitted from the print control unit 20Cc to the colorant ejection heads 21C, 21M, 21Y, and 21K. , Image formation output to form an image.

  The printer engine 20E converts the bit map data input from the DFE 1 to the inkjet device 2 into data corresponding to an image forming output based on an instruction from the printer controller 20C, and the colorant discharge head 21C, the colorant discharge head The data is divided into data for each of 21M, the colorant discharge head 21Y, and the colorant discharge head 21K.

  For example, the printer engine 20E converts the input 256 bit bitmap data into four values of large droplet, medium droplet, small droplet, and no ejection, and the corresponding colorant ejection head 21C, colorant ejection head 21M, and coloring The data is divided into data for each of the agent discharge head 21Y and the colorant discharge head 21K.

  The pre-processing apparatus 3 performs an operation of forming a pre-processing area, which is an area subjected to pre-processing, by discharging the droplet LD onto the roll paper Md based on the pre-processing output data and the control information data input from DFE1. Run. The pretreatment device 3 includes a precoat controller 30C and a precoat engine 30E.

  The pre-coat controller 30C includes a CPU 30Cp and a pretreatment control unit 30Cc, and the CPU 30Cp and the pretreatment control unit 30Cc are connected by a bus 30Cb so as to be able to transmit and receive. The bus 30Cb is connected to the signal line 71LC via the communication I / F. The CPU 30Cp controls the overall operation of the preprocessing device 3 using a control program stored in the ROM.

  The preprocessing control unit 30Cc transmits / receives information such as a command, a parameter, or data to / from the precoat engine 30E based on the control information data transmitted from the DFE 1. The pretreatment control unit 30Cc controls the precoat engine 30E by transmitting and receiving information to and from the precoat engine 30E.

  The precoat controller 30C controls the precoat engine 30E. The precoat controller 30C transmits and receives control information data and the like to and from the DFE 1 through the signal line 30LC. The precoat controller 30C transmits and receives control information data and the like to and from the precoat engine 30E described later via the signal line 30LC.

  The pre-coat controller 30C writes the printing conditions and the like included in the transmitted and received control information data in the register of the preprocessing control unit 30Cc, and stores the printing conditions in the register. The precoat controller 30C controls the precoat engine 30E based on the control information data to execute printing according to the print job data and the control information data.

  The precoat engine 30E has a pretreatment agent discharge control unit 30Eph, 30Epl. The precoat engine 30E converts the bit map data input from the DFE 1 to the preprocessing device 3 into small value data corresponding to the image forming output based on an instruction from the precoat controller 30C, and the pretreatment agent discharge control unit Divide data into 30 Eph and 30 Epl.

  For example, the precoat engine 30E converts the input 256-bit bitmap data into four values of large droplet, medium droplet, small droplet, and no ejection, and converts the data into the corresponding pre-processing agent ejection control units 30Eph and 30Epl. To divide. The pretreatment agent ejection control units 30Eph and 30Epl cause the pretreatment agent ejection heads 31H and 31L to eject the droplets LD onto the roll paper Md, based on the pretreatment output data transmitted from the pretreatment control unit 30Cc, respectively. The pretreatment agent layer PC is formed on the roll paper Md.

  The measuring device 5A includes a measurement control unit 50A. The measurement control unit 50A measures the surface of the roll paper Md over a predetermined range of the width direction and the conveyance direction Xm based on the measurement execution information transmitted from the DFE 1. And based on the measured value, a measurement image is produced | generated and the produced | generated measurement image is transmitted to DFE1.

  Measuring device 5B includes a measurement control unit 50B. The measurement control unit 50B measures the surface of the roll paper Md over a predetermined range of the width direction and the conveyance direction Xm based on the measurement execution information transmitted from the DFE 1. And based on the measured value, a measurement image is produced | generated and the produced | generated measurement image is transmitted to DFE1.

  As described above, in the inkjet system 4 according to the present embodiment, the inkjet device 2 discharges droplets to the roll paper Md subjected to the pretreatment by the pretreatment device 3 based on the drawing information input from the DFE 1. Perform imaging output by Next, the functional configuration of the DFE 1 according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 11, the DFE 1 includes a controller 100, an input / output device 400, and a network I / F 15F. The input / output device 400 is an output interface that visually displays the state of the DFE 1 and is also an input interface when the user directly operates the DFE 1 as a touch panel or inputs information to the DFE 1.

  That is, the input / output device 400 includes a function of displaying an image for receiving an operation by the user. The input / output device 400 is realized by a display device and an operation device connected to the I / F 15.

  The network I / F 15F is an interface for the DFE 1 to communicate with the host terminal and other devices such as the measuring devices 5A and 5B via the network, and uses Ethernet (registered trademark) or USB (Universal Serial Bus) interface. The network I / F 15F can communicate by the TCP / IP protocol. The network I / F 15F is realized by the I / F 15.

  The controller 100 includes a main control unit 110, an engine control unit 120, an image processing unit 130, an operation display control unit 140, and an input / output control unit 150, and is configured by a combination of hardware and software shown in FIG. Specifically, a program stored in the ROM 12 or nonvolatile memory and a nonvolatile storage medium such as the HDD 14 or an optical disk is loaded into a volatile memory (hereinafter, memory) such as the RAM 13.

  The CPU 11 performs an operation in accordance with the program loaded into the RAM 13 or the like. The controller 100 is configured by the software control unit configured by the series of cooperation and hardware such as an integrated circuit. The controller 100 functions as a control unit that controls the entire DFE 1.

  The main control unit 110 plays a role of controlling each unit included in the controller 100, and gives an instruction to each unit of the controller 100. The engine control unit 120 plays a role as a driving unit that controls or drives the inkjet device 2, the pretreatment device 3, the loading unit 17, the unloading unit 60 and the like. The image processing unit 130 generates drawing information such as bitmap data based on the information of the image to be printed out under the control of the main control unit 110. The drawing information is information for drawing the image to be formed in the image forming operation by the inkjet device 2 or the preprocessing device 3, that is, the image of the target of the image formation output.

  The operation display control unit 140 displays information on the input / output device 400 or notifies the main control unit 110 of information input via the input / output device 400. The input / output control unit 150 inputs, to the main control unit 110, information input via the network I / F 15F. In addition, the main control unit 110 controls the input / output control unit 150, and accesses other devices connected to the network via the network I / F 15F and the network.

  As processing executed by the DFE 1, first, the input / output control unit 150 receives a print job, which is instruction information for executing image formation output, from a host apparatus or the like via the network I / F 15 F. The input / output control unit 150 transfers the received print job to the main control unit 110. When the main control unit 110 receives a print job, the main control unit 110 controls the image processing unit 130 to generate drawing information based on document information or image information included in the print job.

  In the print job according to the present embodiment, in addition to the information of the image in which the image information of the output target is described in the information format which can be analyzed by the image processing unit 130 of DFE 1, the information of the parameters to be set at the time of image formation output included. The information of this parameter is, for example, information such as setting of double-sided printing, setting of combined printing, setting of color / monochrome, and the like.

  When drawing information is generated by the image processing unit 130, the engine control unit 120 transmits print output data and preprocessing output data to the inkjet device 2 and the preprocessing device 3 respectively, and based on the generated drawing information, The image formation is performed on the sheet conveyed from the loading unit 17.

  As described above, in the present embodiment, the main control unit 110 controls each unit included in the controller 100. Next, with reference to FIG. 12, a functional configuration of the main control unit 110 which also functions as a pre-processing execution control unit in the present embodiment will be described.

  The main control unit 110 according to the present embodiment includes a characteristic information storage unit 111, a measurement information analysis unit 112, and a pretreatment agent discharge amount calculation unit 113. The characteristic information storage unit 111 includes a medium characteristic information storage unit 114, a pre-processing agent characteristic information storage unit 115, and a colorant characteristic information storage unit 116. The characteristic information data table SD may be stored in the characteristic information storage unit 111.

  As shown in FIGS. 13 to 15, the characteristic information data table SD indicates the discharge amount of the pretreatment agent PCA and the coagulant concentration AGC with respect to the size of the dot formed by the droplet LD adhering to the recording medium M. The relationship with the above is shown as characteristic information for each type of recording medium M.

  The characteristic information data table SD shown in FIGS. 13 to 15 includes medium characteristics (for example, high and low permeability) of the recording medium M, types of pigment particles P contained in the droplets LD, and pretreatment agent PCA. Configured for each combination of types.

  FIG. 13 shows the relationship between the discharge amount of the pretreatment agent PCAa in the low permeability recording medium M and the dot size of the flocculant concentration AGC and the pigment Dy, and FIG. 14 shows the pretreatment agent in the medium permeability recording medium M. FIG. 15 shows the discharge amount of the pre-treatment agent PCAa and the coagulant concentration AGC of the high permeability recording medium M and the dot of the pigment Dy in the relationship between the discharge amount of PCAa and the coagulant concentration AGC and the dot size of the pigment Dy. It is the figure which illustrated the characteristic information data table SD which each shows a relation with size.

  As shown in FIG. 13 to FIG. 15, when an image is formed by discharging the droplet LD after forming the pretreatment agent layer PC on the recording medium M, it is formed by the pigment particles P included in the droplet LD The larger the dots discharged, the larger the discharge amount of the pretreatment agent PCA, and the larger the concentration of the coagulant AG. Further, the dots formed by the pigment particles P contained in the droplet LD become larger as the permeability of the droplet LD to the recording medium M is lower.

  That is, by controlling the discharge amount of the pretreatment agent PCA with reference to the characteristic information data table SD, it is possible to control the size of the dots formed by the pigment particles P for each characteristic of the recording medium M. In other words, by using the characteristic information data table SD, it is possible to speed up or slow down the spread speed of the droplet LD which is an image forming agent and which contains the pigment particles P as a colorant.

  Thus, the characteristic information data table SD includes the dot size, the discharge amount of the pretreatment agent PCA, and the coagulant concentration AGC for each combination of the characteristics of the recording medium M, the type of the pigment particles P, and the type of the pretreatment agent PCA. Includes information configured as a relationship with the

  Further, the characteristic information data table SD indicates the dot size, the discharge amount of the pretreatment agent PCA, and the coagulant concentration AGC for each combination of the characteristics of the recording medium M, the type of the pigment particles P, and the type of the pretreatment agent PCA. The information configured as the relationship may be input as a result of the image forming output, or may be configured by the characteristic information obtained as a result of experiment or simulation.

  In addition, the characteristic information data table SD may be configured by the simulation result indicating the relationship between the discharge amount of the pretreatment agent PCA and the coagulant concentration AGC for each type of the recording medium M or the characteristic information obtained as an experiment result. . The details of the characteristic information data table SD will be described later.

  The medium characteristic information storage unit 114 stores medium characteristic information which is information on physical characteristics of the recording medium M. Here, the medium characteristic information is information indicating whether the recording medium M is a non-permeable medium or a permeable medium, and is information indicating the degree of penetration of the droplet LD into the recording medium M. is there.

  In addition, a film is known as the non-penetrable medium, and plain paper and coated paper etc. are known as the permeable medium. Alternatively, the surface roughness of the surface of the recording medium M may be measured as the medium characteristic information for each recording medium M, and the measured value may be used as the medium characteristic information.

  The pretreatment agent characteristic information storage unit 115 includes pretreatment agent characteristics that are information on the characteristics of the pretreatment agent PCA1 ejected from the pretreatment agent ejection head 31H and the pretreatment agent PCA2 ejected from the pretreatment agent ejection head 31L. Information is stored. The pretreatment agent characteristic information is, for example, information indicating the material and physical characteristics of the pretreatment agent PCA.

  In the colorant characteristic information storage unit 116, colorant characteristic information which is information on the characteristics of each of the Y, M, C, K inks ejected from the colorant ejection head 21 is stored. The colorant characteristic information is, for example, information indicating the material and physical characteristics of the colorant for coloring each color of Y, M, C, and K.

  The main control unit 110 may be configured to add the characteristic information to the characteristic information data table SD with reference to the pre-processing agent characteristic information and the colorant characteristic information based on the execution result of the image formation output. .

  The measurement information analysis unit 112 analyzes the surface characteristic of the recording medium M for each pixel and outputs the analysis result for the measurement image before output input to the main control unit 110 via the input / output control unit 150. .

  The measurement information analysis unit 112 uses, for example, the recording medium M for each pixel of the measurement image based on the relational expression representing the relationship between the gray value of the measurement image on the surface of the recording medium M and the surface characteristics shown in FIG. Output analysis results of surface characteristics of The analysis result of the surface characteristic of the recording medium M does not have to be for each pixel, and may be output for each predetermined area according to the droplet discharge resolution, for example.

  FIG. 16 is a diagram schematically showing a relational expression representing the relationship between the density value of the measurement image on the surface of the recording medium M and the wettability of the droplet LD to the recording medium M. FIG. 17 is a measurement of the surface of the recording medium M FIG. 5 is a diagram schematically showing a relational expression representing the relationship between the density value of the image and the permeability of the droplet LD to the recording medium M.

  In FIG. 16, as the density of the measurement image on the surface of the recording medium M becomes darker, the wettability of the droplet LD with respect to the recording medium M becomes better, and it is shown that the droplet LD adheres to the recording medium M more easily. In FIG. 17, as the density of the measurement image on the surface of the recording medium M increases, the permeability of the droplet LD to the recording medium M increases, and the droplet LD easily penetrates the recording medium M.

  The measurement information analysis unit 112 analyzes the wettability of the droplet LD with respect to the recording medium M based on the information of density of each pixel of the measurement image, and transmits the analysis result to the pretreatment agent discharge amount calculation unit 113. In addition, the measurement information analysis unit 112 analyzes the permeability of the droplet LD to the recording medium M based on the information of density of each pixel of the measurement image, and transmits the analysis result to the pretreatment agent discharge amount calculation unit 113. .

  The pre-treatment agent discharge amount calculation unit 113 is respectively supplied from the pre-treatment agent discharge heads 31H and 31L based on the analysis result of the measurement image by the measurement information analysis unit 112 and the various characteristic information stored in the characteristic information storage unit 111. It functions as a processing droplet discharge amount calculation unit that calculates the amount of pretreatment agent that is the processing droplet discharge amount to be discharged, a first droplet discharge amount calculation unit, and a second droplet discharge amount calculation unit.

  Then, the pretreatment agent PCA is ejected to the recording medium M based on the ejection amount of the pretreatment agent PCA calculated by the pretreatment agent ejection amount calculation unit 113 to form the pretreatment agent layer PC, whereby the recording medium is formed. Control the behavior of the droplet LD containing the imaging agent on the M surface.

  Next, the difference in the formation mode of the pretreatment agent layer PC on the recording medium M will be described with reference to FIG. First, when the pretreatment agent PCA is discharged onto the recording medium M, the pretreatment agent layer PC is formed on the surface of the recording medium M as shown in FIG.

  The amount of pretreatment agent PCA discharged to the area of (a) and the area of (b) and the concentration of the coagulant concentration AGC are the same, and the area shown in (a) and the area shown in (b) The description will be made on the assumption that the permeability of the droplet LD to the recording medium M is different.

  At this time, in the area shown in FIG. 18A and the area shown in FIG. 18B, the permeability of the droplet LD to the recording medium M is different. Specifically, the coagulant AG is easily moved in the thickness direction of the recording medium M in the area shown in (b) because the coagulant AG is smaller than the void of the recording medium M, or the like.

  Therefore, a difference occurs in the behavior of the droplet LD containing the pretreatment agent PCA with respect to the recording medium M, and in the area of (b), the pretreatment in the thickness direction of the recording medium M is larger than the area of (a). The agent layer PC is formed.

  Compared with the distribution mode of the coagulant AG in the area of (a), in the area of (b), the coagulant AG diffuses in the thickness direction of the recording medium M, and is larger in the thickness direction of the recording medium M The pretreatment agent layer PC is formed in the range. Therefore, in the pretreatment agent layer PC formed in the region of (b), the concentration of the aggregating agent AG is lower than that of the pretreatment agent layer PC formed in the region of (a).

  Therefore, the coagulant concentration AGC in the thickness direction of the recording medium M is different between the pretreatment agent layer PC in the region (a) and the pretreatment agent layer PC in the region (b). In the region (b), since the coagulant AG is distributed at a position farther than the surface of the recording medium M, the amount per unit time of the coagulant AG diffused to the droplets LD attached to the recording medium M is , Compared to the area of (a).

  On the other hand, in the area of (a), since the coagulant AG is distributed at a position close to the surface of the recording medium M, the amount per unit time of the coagulant AG diffused to the droplets LD attached to the recording medium M Is larger than the region of (b).

  Therefore, when the droplets LD are discharged to the respective regions (a) and (b), a difference occurs in the amount of the aggregating agent AG diffused to the droplets LD discharged to the respective regions. As a result, a difference occurs in the behavior of the ejected droplet LD, and a difference also occurs in the size of the dot formed by the pigment particle P.

  Therefore, in the present embodiment, as shown in FIG. 19, the behavior of the droplet LD containing the image forming agent on the surface of the recording medium M is controlled to form a desired dot by the image forming agent. Control the execution mode of the pretreatment based on the surface characteristics of Specifically, the main control unit 110 controls the discharge amounts of the pretreatment agent PCA1 and pretreatment agent PCA2 having different coagulant concentration AGC based on the surface characteristics of the recording medium M to form a pretreatment agent layer PC.

  Specifically, the area shown in (a) of FIG. 19 is an area analyzed by the measurement information analysis unit 112 as having low permeability of the droplet LD to the recording medium M. The area shown in (b) of FIG. 19 is an area analyzed by the measurement information analysis unit 112 as having high permeability of the droplet LD to the recording medium M.

  At this time, the pre-processing agent discharge amount calculation unit 113 makes the amount of the coagulant AG per unit time diffused to the droplet LD adhering to the region shown in (a) and the region shown in (b) become equal. The discharge amounts of the pretreatment agent PCA1 and the pretreatment agent PCA2 are calculated. By doing this, the pretreatment apparatus 3 can execute pretreatment on the recording medium M such that the behavior of the droplet LD becomes constant.

  In FIG. 19, the pretreatment agent layer PC is formed so that the surface of the recording medium M is horizontal, but the pretreatment agent PCA1 is not limited to the recording medium M so that the surface of the recording medium M is horizontal. And it is not necessary to discharge pretreatment agent PCA2 and to form pretreatment agent layer PC.

  Thus, the information on the discharge amounts of the pretreatment agent PCA1 and the pretreatment agent PCA2 calculated by the pretreatment agent discharge amount calculation unit 113 is sent to the pretreatment device 3 by the main control unit 110 via the engine control unit 120. Will be sent.

  In the present embodiment, the pretreatment device 3 discharges the pretreatment agent ejection head 31H for ejecting the pretreatment agent PCA1 having a high concentration of the coagulant AG and the pretreatment agent for ejecting the pretreatment agent PCA2 having a low concentration of the coagulant AG. It includes a head 31L. Then, as shown in FIG. 20, the pretreatment device 3 is provided with a pretreatment agent PCA1 having a concentration of the coagulant AG higher than that of the recording medium M from each of the pretreatment agent ejection head 31H and the pretreatment agent ejection head 31L. The pretreatment agent PCA2 having a low concentration of the coagulant AG is discharged.

  As shown in FIG. 20, the pretreatment agent layer PC1 is formed in the region where the pretreatment agent PCA1 is discharged, and the pretreatment agent layer PC2 is formed in the region where the pretreatment agent PCA2 is discharged. Here, it is assumed that a droplet LD, which is an image forming agent containing pigment particles P, is discharged to the pretreatment agent layer PC shown in FIG.

  At this time, as shown in FIG. 19, in the pretreatment agent layer PC1, the concentration of the coagulant AG is low, and the pretreatment agent layer PC is formed in the vicinity of the surface of the recording medium M. On the other hand, the pretreatment agent layer PC2 has a high concentration of the coagulant AG, and the pretreatment agent layer PC is formed to be larger in the thickness direction of the recording medium M than the pretreatment agent layer PC1.

  At this time, since the amount of aggregating agent AG per unit time diffused to the droplets LD adhering to the pretreatment agent layer PC1 and the pretreatment agent layer PC2 is the same, the pretreatment agent layer PC1 and the pretreatment The droplets LD attached to the agent layer PC2 form dots of the same size.

  As described above, in the inkjet system 4 according to the present embodiment, the behavior on the recording medium M of the droplet LD including the coloring agent according to the concentration of the coagulant AG in the pretreatment agent layer PC formed on the recording medium M Are controlled to control the size of the dot and the shape of the dot, which is a colored area formed by the droplet LD adhering to the recording medium M.

  The pretreatment agent ejection amount calculation unit 113 causes the pretreatment agent ejection head 31H and the pretreatment agent ejection head 31L to eject the pretreatment agents PCA1 and PCA2 to the same region on the recording medium M, respectively. The first processing droplet ejection amount and the second processing droplet ejection amount, which are the ejection amounts of the pretreatment agents PCA1 and PCA2, may be calculated. At this time, the pretreatment device 3 controls the ejection timings of the pretreatment agent ejection head 31H and the pretreatment agent ejection head 31L, and ejects the pretreatment agent PCA1 and the pretreatment agent PCA2 to the same area to carry out the pretreatment agent layer. Form a PC.

  Next, the flow of the process of calculating the amount (discharge amount) of the pretreatment agent PCA to be discharged in the inkjet system 4 according to the present embodiment will be described with reference to the flowchart of FIG. When the main control unit 110 receives the job data (S2101), the main control unit 110 transfers the received job data to the image processing unit 130.

  The image processing unit 130 sets printing conditions specified in the job data to the image information based on the job data, executes RIP (Raster Image Processing) processing, and executes bitmap processing for image formation output Drawing information such as data is generated (S2102).

  At this time, as setting information for setting printing conditions and generating drawing information, for example, medium setting information for setting the recording medium M, and density of an image to be formed and output are set in job data. It includes density setting information, color setting information for setting whether to execute image formation output in color or monochrome, and mode setting information to be set when image formation output is precisely performed.

  The image processing unit 130 transmits the drawing information and the setting information generated by the RIP process to the main control unit 110 (S2103). When the main control unit 110 receives the drawing information and the setting information, the main control unit 110 causes the measuring device 5A to measure the recording medium M via the input / output control unit 150, acquires one measurement image as a measurement result (S2104), and measures It is transmitted to the information analysis unit 112.

  The measurement information analysis unit 112 analyzes the surface characteristics (for example, the wettability and permeability) of the area of the recording medium M corresponding to the measurement image based on the measurement image, and analyzes the analysis result as the pretreatment agent discharge amount calculation unit 113. To (S2105).

  Next, the pretreatment agent discharge amount calculation unit 113 refers to the characteristic information storage unit 111, and acquires pretreatment agent characteristic information and colorant characteristic information (S2106). At this time, the pretreatment agent discharge amount calculation unit 113 may acquire the characteristic information from the characteristic information data table SD.

  The pretreatment agent discharge amount calculation unit 113 performs preprocessing for each pixel obtained from the analysis result based on the characteristic information acquired in S2106 and the analysis result of the surface characteristic of the recording medium M received from the measurement information analysis unit 112. The discharge amounts of the agents PCA1 and PCA2 are calculated (S2107). Thus, when different analysis results are obtained at the position of the surface of the recording medium M, the execution mode of the pre-processing is changed according to the droplet LD discharged onto the recording medium M, depending on the position of the recording medium M.

  In the process of S2107, the discharge amount of the pretreatment agents PCA1 and PCA2 may be calculated by setting the discharge amount of either the pretreatment agent PCA1 or the pretreatment agent PCA2 to “0”. The pre-processing agent amount information, which is information on the calculated discharge amounts of the pre-processing agents PCA1 and PCA2, is transmitted to the pre-processing device 3 by the main control unit 110 via the engine control unit 120 (S2108).

  Next, in the inkjet system 4 according to the present embodiment, a flow of processing for performing image formation output will be described. The main control unit 110 transmits preprocessing execution information that causes the preprocessing device 3 to execute preprocessing.

  When the pretreatment device 3 receives the pretreatment execution information from the DFE 1, the pretreatment device 3 discharges the pretreatment agent PCA 1 and the pretreatment agent PCA 2 to the recording medium M based on the pretreatment agent amount information received from the DFE 1 in S 2108 Execute pre-processing.

  The main control unit 110 transmits the image formation execution information to the inkjet device 2. The inkjet device 2 is colored at the timing when the recording medium M subjected to the pretreatment by the pretreatment device 3 is conveyed to the inkjet device 2 and reaches the ejection positions of the colorant ejection heads 21K, 21C, 21M, and 21Y. The colored droplets containing the agent are discharged onto the recording medium M.

  The position measured by the measuring device 5A, the position at which the preprocessing device 3 performed preprocessing, and the position at which the colorant discharge head 21 discharges are managed as the transport position of the recording medium M, respectively. An image is formed on the recording medium M by the measurement device 5A, the pre-processing device 3 and the colorant discharge head 21 operating in synchronization with each other.

  Therefore, the main control unit 110 functions as a droplet discharge control unit that causes the inkjet device 2 and the pretreatment device 3 to discharge droplets. Further, the main control unit 110 causes a processing droplet discharge execution control unit to cause the preprocessing device 3 to discharge processing droplets such as the pretreatment agent PCA, and a coloring to cause the inkjet device 2 to discharge colored droplets containing a coloring agent. It also functions as a droplet discharge execution control unit. The recording medium M on which the image is formed is discharged from the discharge unit 60.

  As described above, in the present embodiment, by forming the pretreatment agent layer PC based on the surface characteristics of the recording medium M, the behavior of the ejected droplet LD is controlled, and the pigment contained in the droplet LD The shape of the dots formed by the particles P is made to be a desired shape.

  In the present embodiment, it is assumed that the pretreatment agent layer PC1 is formed in the region where the pretreatment agent PCA1 is discharged, and the pretreatment agent layer PC2 is formed in the region where the pretreatment agent PCA2 is discharged. Although it carried out, you may discharge pretreatment agent PCA1 and pretreatment agent PCA2 to the same area | region, and may form pretreatment agent layer PC. In this way, the coagulant concentration AGC in the pretreatment agent layer PC can be controlled more finely.

  From the above, in the present embodiment, for example, when a medium such as plain paper, coated paper, wood, or the like whose surface shape is not constant in the thickness direction is subjected to pretreatment, and then the ink is discharged, the medium The wettability and permeability of the ink can be made constant. Therefore, since the behavior of the ink ejected on the medium can be made constant, the uniform ink shape can be formed on the medium.

  In addition, since it is possible to form a pretreatment area having wettability and permeability according to the ink for each position of the medium according to the information of the ink ejected onto the medium and the surface characteristics of the medium, image formation with good quality is possible. Can be performed.

  In addition to the pigment particles P, biomolecules such as dyes, proteins, lipids, nucleic acids, hormones, sugars, amino acids, etc., are contained in the droplets LD discharged from the inkjet device 2 and the pretreatment device 3 to the recording medium M. , Resins, polymers and the like may be used. In addition to the coagulant AG, a chelating agent, a fibrin-based adhesive, a hydroxyapatite, a polymerization agent, and the like may be used as a reactive agent contained in the pretreatment agent PCA.

  Furthermore, the inkjet system 4 which concerns on this embodiment is applicable also to three-dimensional model | modeling apparatuses, such as 3D printer.

  The measurement device 5A may have the same function as the measurement information analysis unit 112, and the measurement device 5A and the measurement device 5B may analyze the measurement image before output. Then, the measuring apparatus 5A transmits the analysis result of the measurement image before output to the DFE 1.

  In such a case, the pretreatment agent discharge amount calculation unit 113 calculates the ejection amount of the pretreatment agent PCA based on the surface characteristic of the recording medium M transmitted from the measuring device 5A to the DFE 1.

Second Embodiment
In this embodiment, a serial head type ink jet apparatus will be described by way of example, which transports a recording medium and executes image formation output by droplets discharged from a discharge head moving in the main scanning direction. The same components as those in the first embodiment are given the same reference numerals, and redundant description will be omitted.

  FIG. 22 is a view showing an outline of the ink jet system 4 according to the present embodiment. The inkjet system 4 is configured by connecting the DFE 1 and the image forming apparatus 6 by a communication line. The image forming apparatus 6 according to the present embodiment is configured by integrating the inkjet apparatus 2 and the pre-processing apparatus 3 according to the first embodiment into one casing.

  Next, the configuration of the image forming apparatus 6 according to the present embodiment will be described with reference to the perspective views of the image forming apparatus 6 of FIGS. 23 and 24. FIG. The image forming apparatus 6 includes an inkjet apparatus 2, a pretreatment apparatus 3, measurement apparatuses 5A and 5B, and a carriage 101 for moving the inkjet apparatus 2 and the pretreatment apparatus 3 in the main scanning direction inside the apparatus body.

  The carriage 101 is slidably disposed in the main scanning direction (the direction perpendicular to the transport direction Xm) by the main guide rod 107 and the secondary guide rod 107b which are guide members laterally extended on the left and right side plates. . On the carriage 101, the inkjet device 2 and the pretreatment device 3 are mounted. Further, the measuring device 5A is mounted on the side surface of the carriage 101 on the side of the pretreatment device 3 and the measuring device 5B is mounted on the side surface of the carriage 101 on the side of the ink jet device 2.

  Then, the colorant ejection head 21 mounted on the inkjet device 2 ejects the colorant of each color of YMCK, and the pretreatment agent ejection head 31 mounted on the pretreatment device 3 records the pretreatment agent PCA as a recording medium. Discharge to M. The colorant ejection head 21 and the pretreatment agent ejection head 31 are arranged in a direction intersecting the main scanning direction, and the nozzle 40N is configured to open downward.

  The cartridge 103 for supplying the droplet LD including the colorant of each color to the colorant ejection head 21 and the droplet LD including the pretreatment agent PCA to the pretreatment agent ejection head 31 can be replaced to the carriage 101 so as to be replaceable. It is attached. In addition, the cartridge 103 has an atmosphere port communicating with the atmosphere at the upper side, and a supply port for supplying the droplet LD to the colorant ejection head 21 or the pretreatment agent ejection head 31 at the lower side. The cartridge 103 is configured to have a porous body filled with the droplet LD.

  The internal pressure of the cartridge 103 is maintained so that the droplet LD supplied by the capillary force of the porous body has a slight negative pressure. In the present embodiment, although the case where the colorant discharge head 21 is provided for each color is taken as an example, it may be a single head having a nozzle 40N for discharging the droplets LD of each color of YMCK.

  Furthermore, although the pretreatment agent discharge head 31 is also provided for each concentration of the coagulant AG as an example, it may be a single head having a nozzle 40N for discharging the droplets LD of the coagulant AG having different concentrations. .

  The carriage 101 is slidably attached to the main guide rod 107 on the rear side (downstream side in the sheet conveying direction) and slidably attached to the secondary guide rod 107 b on the front side (upstream side in the sheet conveying direction). Further, in order to move and scan the carriage 101 in the main scanning direction, a timing belt 212 is bridged between a driving pulley 210 and a driven pulley 211 which are rotationally driven by the main scanning motor 109. The timing belt 212 and the carriage 101 are fixed, and the carriage 101 is driven to reciprocate by forward and reverse rotation of the main scanning motor 109.

  On the other hand, in order to transport the recording medium M stacked in the paper feeding cassette 204 to the lower side of the ink jet head 102, the paper feeding roller 213 and friction pad 214 for separately feeding the recording medium M from the paper feeding cassette 204; A guide member 215 for guiding the medium M, a conveyance roller 216 for inverting and conveying the conveyed recording medium M, delivery of the recording medium M from the conveyance roller 118a pressed against the circumferential surface of the conveyance roller 216 and the conveyance roller 216 A tip roller 118b for defining an angle is provided. The conveyance roller 216 is rotationally driven by the sub scanning motor via a gear train.

  Printing which is a guide member for guiding the recording medium M sent from the conveyance roller 216 corresponding to the range in the main scanning direction in which the carriage 101 moves, below the coloring agent discharge head 21 and the pretreatment agent discharge head 31 A receiving member 119 is provided.

  The recording medium M is rotationally driven to be discharged in the direction of being discharged to the outside of the casing of the image forming apparatus 6 on the downstream side of the direction in which the recording medium M is conveyed to the printing receiving member 119 A conveying roller 220 and a spur 121 are provided. Further, a discharge roller 122 and a spur 123 for feeding the recording medium M to the discharge tray 106, and guide members 124 and 125 for forming a path for discharging the recording medium M to the outside of the casing of the image forming apparatus 6 are arranged. ing.

  Next, the functional configuration of the image forming apparatus 6 according to the present embodiment will be described with reference to FIG. The image forming apparatus 6 according to the present embodiment is configured by adding a transport control unit 60C that controls the transport of the recording medium M to the functions of the inkjet device 2 and the preprocessing device 3 illustrated in FIG.

  The transport control unit 60C transports the recording medium M by driving the sub-scanning motor based on the instruction information received from the print control unit 20Cc and the pre-processing control unit 30Cc. The print control unit 20Cc and the pre-processing control unit 30Cc also function as a drive control unit that controls the drive of the main scanning motor 109. The other configuration is the same as that shown in FIG.

  In the present embodiment, the image forming apparatus 6 is configured by integrating the inkjet apparatus 2 and the pre-processing apparatus 3 into one case. Therefore, the configuration may be such that each unit of the image forming apparatus 6 is controlled based on the information received from the main control unit 110 by the image forming controller which is a control unit that controls the operation of the image forming apparatus 6.

  In such a case, the image forming controller causes the printer engine 20E to control the operation of the colorant discharge head 21 and the precoat engine 30E to control the operation of the pretreatment agent discharge head 31 based on the information received from the main control unit 110. . At this time, the main control unit 110 functions as a droplet discharge control unit that causes the image forming apparatus 6 to discharge droplets.

  Using the image forming apparatus 6 configured as described above, the inkjet system 4 according to the present embodiment executes an image formation output based on the information of the image. Next, in the inkjet system 4 according to the present embodiment, the flow of processing for performing image formation output will be described with reference to FIG.

  When the DFE 1 ends the process shown in the flowchart of FIG. 21, the main control unit 110 transmits preprocessing execution information to cause the preprocessing device 3 to execute preprocessing (S2601). The pre-processing device 3 discharges the pre-processing agent PCA1 and the pre-processing agent PCA2 to the recording medium M based on the pre-processing execution information received from the DFE 1 to execute pre-processing.

  When the pretreatment agent ejection heads 31H and 31L eject the droplets LD onto the recording medium M, the pretreatment control unit 30Cc drives the pretreatment agent ejection heads 31H and 31L based on the drawing information while moving the carriage 101. The droplet LD including the pretreatment agent PCA is ejected by one band in the main scanning direction to the recording medium M which has been stopped (S2602). When the ejection for one band is completed, the preprocessing device 3 transmits, to the DFE 1, a preprocessing completion notification for which the preprocessing for one band has been performed (S 2603).

  When the DFE 1 receives the preprocessing completion notification from the preprocessing device 3, it transmits transport execution information for transporting the recording medium M by one band in the sub scanning direction to the image forming apparatus 6 (S2604). The image forming apparatus 6 causes the conveyance control unit 60C to drive the sub scanning motor according to the conveyance execution information, conveys the recording medium M by one band in the sub scanning direction by the conveyance roller 216 (S2605), and notifies the conveyance completion to DFE1. It transmits (S2606).

  When the DFE 1 receives the conveyance execution notification, the DFE 1 transmits image formation execution information for causing the inkjet device 2 to execute image formation output for one band (S2607). When the colorant discharge head 21 discharges the droplet LD onto the recording medium M, the print control unit 20Cc drives the colorant discharge head 21 of each color based on the drawing information while moving the carriage 101 and stops. One band of a droplet LD containing a colorant of each color is discharged to the recording medium M in the main scanning direction (S2608).

  When the ejection for one band is completed, the inkjet device 2 causes the print control unit 20Cc to drive the sub scanning motor to convey the recording medium M, and transmits an image formation completion notification to the DFE 1 (S2609).

  The DFE 1 transmits discharge execution information for discharging the recording medium M to the image forming apparatus 6 when all the image formation output of the drawing information included in the job data is finished (S2610), and drives the sub scanning motor The recording medium M on which the recording medium M is formed is discharged (S2611). If the image formation output of the drawing information included in the job data has not been completed for all bands, DFE 1 is re-executed from the process of S2101.

Third Embodiment
In the present embodiment, an inkjet system 4 that analyzes an image formed and output and feedback-controls the discharge amount of the pretreatment agent PCA based on the analysis result will be described as an example. In addition, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant description will be omitted.

  The inkjet system 4 according to the present embodiment is configured in the same manner as the inkjet system 4 described in the first embodiment. FIG. 27 is a diagram showing a functional configuration of the main control unit 110 according to the present embodiment. The main control unit 110 according to the present embodiment is configured by adding a feedback control unit 117 to the configuration shown in FIG.

  The feedback control unit 117 determines whether a desired dot is formed on the recording medium M based on the output measurement image and the drawing information which are measurement information after image formation output acquired from the measuring device 5B. It functions as a shape comparison unit. Then, based on the determination result, the feedback control unit 117 functions as a discharge amount correction unit that performs feedback control to correct the discharge amount of the pretreatment agent PCA calculated by the pretreatment agent discharge amount calculation unit 113.

  The feedback control unit 117 compares, for example, the size and area of the dots in the dot shape of the output measurement image and the drawing information, and determines how much difference occurs. At this time, if the image to be formed and output is a line, a surface, or a dot formed by overlapping multiple color pigment particles P, the feedback control unit 117 sets the shape of a single dot. It can not be detected.

  In such a case, the feedback control unit 117 compares the sizes and areas of the dots only in the pixels in which the sizes and areas of the dots can be compared in the image formed and output, and a difference occurs to some extent. It may be determined whether it is present.

  Further, the determination as to whether or not the desired dot is formed on the recording medium M performed by the feedback control unit 117 does not need to be continuously performed while the image forming output operation is performed, for example, every morning or every six hours For example, the configuration may be performed periodically.

  Further, the feedback control unit 117 forms a test pattern of dots that can determine whether a desired dot is formed on the recording medium M, compares the size and area of the dot, etc. It may be configured to determine whether or not there is a difference.

  The feedback control unit 117 compares the size and the area of the dot in the measurement image after output and the drawing information, and when it is determined that a difference equal to or more than a predetermined value has occurred, the characteristic information shown in FIGS. The discharge amount of the pretreatment agent PCA calculated by the pretreatment agent discharge amount calculation unit 113 is controlled based on the value of the data table SD.

  Specifically, when the size and area of the dot in the measurement image after output are larger than the size and area of the dot in the drawing information, the feedback control unit 117 has a concentration lower than that of the coagulant concentration AGC of the previous pretreatment agent PCA2. The pretreatment agent PCA1 containing the flocculant AG of Alternatively, feedback control is performed to reduce the discharge amount of the pretreatment agent PCA2.

  At this time, in the area where the permeability of the recording medium M is high, since the size of the dots decreases, feedback control is performed so that the dots become large, and in the area where the permeability of the recording medium M is low, As the dots become larger, feedback control may be performed so that the size of the dots becomes smaller.

  Next, the flow of feedback control according to the present embodiment will be described with reference to FIG. The main control unit 110 is instructed to execute feedback by, for example, performing an operation of instructing the execution of feedback control by the user of the inkjet system 4 from the input / output device 400 after a predetermined time has elapsed since the previous execution of image formation output. Information is input (S2801).

  When feedback execution instruction information is input, the feedback control unit 117 acquires a post-output measurement image which is measurement information after image formation output from the measurement device 5B (S2802). Then, the feedback control unit 117 compares the output measurement image with the drawing information, and based on the comparison result, determines whether a desired dot is formed on the recording medium M (S2803).

  Then, the feedback control unit 117 performs feedback control of the discharge amount of the pretreatment agent PCA calculated by the pretreatment agent discharge amount calculation unit 113 based on the determination result (S2804).

  As described above, in the inkjet system 4 according to the present embodiment, the values of the characteristic information data table SD are set so that the shape of the dots that are colored areas formed by discharging the image forming agent onto the recording medium M does not change. The discharge amount of the pretreatment agent PCA calculated by the pretreatment agent discharge amount calculation unit 113 is controlled based on the above.

  The measuring device 5B may have the same function as that of the feedback control unit 117, and the measuring device 5B may analyze the measurement image after output. Then, the measuring apparatus 5B transmits the analysis result of the measurement image after output to the DFE 1.

  In such a case, the feedback control unit 117 of the DFE 1 executes feedback control on the discharge amount of the pretreatment agent PCA calculated by the pretreatment agent discharge amount calculation unit 113 based on the analysis result received from the measuring device 5B. Do.

  The above-described DFE 1 may be a dedicated device or may be realized by installing predetermined software in a server device or a personal computer.

  Also, the DFE 1 does not have to be separate from the inkjet device, and may be realized by a controller inside the inkjet device. Further, among the functions of DFE 1, the function of instructing the preprocessing device 3 based on the output of the measurement control unit 50A may be realized by a controller in the preprocessing device 3. Furthermore, the DFE 1, the controller in the inkjet device 2, and the controller in the preprocessing device 3 may cooperate to realize the DFE 1 function.

  Further, although the recording medium M is conveyed in the embodiment described above, the recording medium M may not be conveyed. For example, in the flatbed method, a recording medium M is disposed on a table, and a carriage on which the colorant discharge head 21 and the pretreatment agent discharge head 31 are mounted moves in a two-dimensional direction to form an image on the recording medium M. It is applicable also to an ink jet device.

  Moreover, although the pre-processing apparatus 3 mentioned above was demonstrated by the example of the apparatus which discharges a pre-processing liquid, the apparatus which performs other pre-processing may be sufficient. For example, when the pretreatment device 3 can finely change the plasma processing based on the surface characteristics of the recording medium M, the pretreatment device 3 applies the recording medium M to the recording medium M based on the measurement results of the measuring devices 5A and 5B. The intensity of the plasma treatment to be performed may be changed for each position.

1 DFE
Reference Signs List 2 inkjet apparatus 3 pre-processing apparatus 4 inkjet system 5A, 5B measurement apparatus 6 image forming apparatus 11 CPU
12 ROM
13 RAM
14 HDD
15 I / F
15F Network I / F
16 Bus 21 Colorant Discharge Head 31 Pretreatment Agent Discharge Head 100 Controller 110 Main Control Unit 111 Characteristic Information Storage Unit 112 Measurement Information Analysis Unit 113 Pretreatment Agent Discharge Amount Calculation Unit 114 Medium Characteristic Information Storage Unit 115 Pretreatment Agent Characteristic Information Storage Unit 116 Colorant characteristic information storage unit 117 Feedback control unit SD characteristic information data table

JP, 2015-189110, A

Claims (10)

A surface characteristic measurement unit that measures the surface characteristic of the medium;
A pre-processing execution unit for pre-processing the medium;
A pre-processing execution control unit configured to control an execution mode of the pre-processing for each position of the medium based on the surface characteristic;
A pre-processing apparatus characterized by including. The pre-processing execution control unit
2. The pre-processing apparatus according to claim 1, wherein an execution mode of the pre-processing is controlled for each position of the medium such that the behavior of droplets ejected onto the medium becomes constant. The pre-processing execution control unit
The execution mode of the pretreatment is controlled for each position of the medium based on the information of the droplets ejected onto the medium and the surface characteristics. Preprocessor. The pre-processing execution control unit
The execution mode of the pre-processing is controlled for each position of the medium so that the spreading speed of the droplets discharged onto the medium becomes small. The pre-processing apparatus as described in a term. The pre-processing execution control unit
The execution mode of the pre-processing is controlled for each position of the medium so as to increase the wetting and spreading speed of droplets discharged onto the medium. The pre-processing apparatus as described in a term. The pre-processing execution unit
As the pre-processing, the medium is subjected to a process for controlling the behavior of the droplet by changing the dispersion state of the coloring agent contained in the droplet discharged onto the medium. The pretreatment device according to any one of claims 1 to 5. The pre-processing execution unit
7. The pretreatment device according to claim 6, wherein the pretreatment agent for changing the dispersion state of the colorant contained in the droplets ejected onto the medium is ejected to the medium. The pre-processing execution unit
7. The pre-processing apparatus according to claim 6, wherein plasma processing is performed to change the dispersion state of the coloring agent contained in the droplets discharged onto the medium to the medium. A pretreatment device according to any one of claims 1 to 8,
A droplet discharge device that discharges droplets onto a medium to execute image formation output;
An inkjet system characterized by including: Measure the surface characteristics of the medium,
A pre-processing method comprising controlling an execution mode of the pre-processing for each position of the medium based on the surface characteristic when performing pre-processing on the medium.