JP7021487B2 - Pretreatment equipment, inkjet system, pretreatment method - Google Patents

Description

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

A printer that employs an inkjet method (hereinafter referred to as an "inkjet device") is known as one aspect of a device used for outputting digitized information. The image forming output, which is one aspect of the information output in the inkjet device, ejects ink or the like used for forming an image from a recording head and attaches it to a medium (for example, paper) forming an image.

By controlling the amount of ink attached to the medium, the dots of the ink forming the image can be made into a predetermined size, and the dots of the ink can be attached to the medium so as to be arranged in a two-dimensional direction to form an image. can.

In the image formation output using the inkjet method, the gradation and gradation of the image can be delicately expressed by adjusting the size of the dots of the ink and making adjustments such as making the arrangement coarse and dense.

However, the inkjet method has a problem that causes deterioration of the quality of the image formed on the medium. That is, depending on the speed at which the wetting of the ink spreads, the ink adhering to the medium flows on the medium, or the ink spreads on the medium, causing a beading phenomenon in which the dots of the ink are connected to each other. Bleed phenomenon such as bleeding of ink dots occurs. Such a phenomenon deteriorates the quality of the image formed on the medium.

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

In Patent Document 1, pretreatment according to the type of medium is uniformly performed on one surface of the medium. Therefore, even if the technique disclosed in Patent Document 1 is applied, the shape of the surface of the medium differs depending on the position on the medium, so that the behavior of the ink with respect to the medium cannot be controlled and the ink is formed on the medium. It deteriorates the quality of the image.

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

In order to solve the above problems, one aspect of the present invention is to apply a treatment agent that agglomerates the particles of the colorant onto the medium before the treatment of ejecting the droplets containing the colorant into the medium. A pretreatment device that executes a pretreatment for forming a layer, and is a surface property measuring unit that measures the surface characteristics of the medium, and a colorant before the treatment of ejecting droplets containing the colorant onto the medium. A pretreatment execution unit that applies a treatment agent having a property of aggregating particles to the medium to form a pretreatment agent layer on the medium, and a pretreatment unit for each position of the medium based on the surface characteristics. The pretreatment execution unit includes a pretreatment execution control unit that controls an execution mode of the treatment, and the pretreatment execution unit is a colorant contained in droplets ejected onto the medium with respect to the medium as the pretreatment. A process for controlling the behavior of the droplet by changing the dispersion state is executed , and the pretreatment execution control unit of the medium so that the behavior of the droplet ejected on the medium becomes constant. It is characterized in that the execution mode of the preprocessing is controlled for each position .

According to the present invention, it is possible to control the behavior of droplets ejected from an inkjet device to enable high-quality image formation.

Explanatory drawing explaining the fluidity of a droplet. The figure which shows the dispersion state of the pigment particles with respect to a solvent. The figure which shows the measurement image which measured the shape of the surface of a recording medium. The figure which shows the cross section of a recording medium. The figure which shows the outline of the inkjet system which concerns on 1st Embodiment of this invention. The block diagram of the ejection head which ejects a droplet which concerns on 1st Embodiment of this invention. The cross-sectional view which shows the schematic structure of the colorant discharge head which concerns on 1st Embodiment of this invention. The figure which shows the operation mode of the inkjet system which concerns on this Embodiment which concerns on 1st Embodiment of this invention. The figure which shows the hardware composition of DFE which concerns on 1st Embodiment of this invention. The block diagram which shows the functional structure of the inkjet apparatus and the pretreatment apparatus which concerns on 1st Embodiment of this invention. The block diagram which shows the functional structure of DFE which concerns on 1st Embodiment of this invention. The block diagram which shows the functional structure of the main control part which concerns on 1st Embodiment of this invention. The figure which shows the structure of the characteristic information data table which concerns on 1st Embodiment of this invention. The figure which shows the structure of the characteristic information data table which concerns on 1st Embodiment of this invention. The figure which shows the structure of the characteristic information data table which concerns on 1st Embodiment of this invention. The figure which shows the relationship between the shading value of the measured image of the surface of the recording medium which concerns on 1st Embodiment of this invention, and the surface characteristic. The figure which shows the relationship between the shading value of the measured image of the surface of the recording medium which concerns on 1st Embodiment of this invention, and the surface characteristic. The figure which shows the formation mode of the pretreatment agent layer which concerns on 1st Embodiment of this invention. The figure which shows the formation mode of the pretreatment agent layer which concerns on 1st Embodiment of this invention. The figure which shows the ejection mode of the droplet which concerns on 1st Embodiment of this invention. The flowchart which shows the flow of the process which calculates the amount of the pretreatment agent which concerns on 1st Embodiment of this invention. The figure which shows the outline of the inkjet system which concerns on the 2nd Embodiment of this invention. The perspective view of the image forming apparatus which concerns on 2nd Embodiment of this invention. The perspective view of the image forming apparatus which concerns on 2nd Embodiment of this invention. The figure which shows the functional structure of the image forming apparatus which concerns on 2nd Embodiment of this invention. The sequence diagram which shows the flow of the process which performs the image formation output which concerns on the 2nd Embodiment of this invention. The figure which shows the functional structure of the main control part which concerns on 3rd Embodiment of this invention. The flowchart which shows the flow of the feedback control which concerns on 3rd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. An embodiment described below is for forming an image, which is an example of an image forming object, by ejecting ink, which is an example of an image forming agent according to the present invention, onto printing paper, which is an example of a medium. First, the fluidity of the ink droplets will be described as an example of the behavior of the ink droplets ejected on a recording medium such as printing paper.

1 (a) to 1 (c) are explanatory views illustrating the fluidity of a droplet LD, which is an ink droplet containing a colorant such as a pigment, with respect to a recording medium M. FIG. 1A is a diagram showing a state immediately before the droplet LD is ejected and comes into contact with the recording medium M which is a printing paper. As shown in FIG. 1A, the droplet LD is composed of the pigment particles P and the solvent L.

Further, it is assumed that the surface of the recording medium M is coated with a flocculant AG, which is a treatment agent (reactant) that changes the dispersed state of the pigment particles P to coagulate the pigment particles P. The process of applying the flocculant AG to the surface of the recording medium M is called "pretreatment". The pretreatment is performed in advance before ejecting the droplet LD. By this pretreatment, the pretreatment agent layer PC is formed on the surface of the recording medium M, which is the ejection destination of the droplet LD.

FIG. 1A is a diagram showing a dispersed state of the pigment particles P with respect to the solvent L immediately before the droplet LD comes into contact with the recording medium M. As shown in FIG. 1A, the droplet LD is formed in a state where the pigment particles P are dispersed in the solvent L. In the case of a pigment ink containing a pigment as a colorant, the pigment particles P are uniformly dispersed in a solvent L such as a solvent or a resin.

FIG. 1B is a diagram showing a dispersed 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 droplet LD adheres to the recording medium M, the pigment particles P are aggregated by the flocculant AG contained in the pretreatment agent layer PC, and the dispersed state of the pigment particles P with respect to the solvent L becomes non-uniform.

FIG. 2 illustrates the dispersed state of the pigment particles P in the droplet LD with respect to the solvent L. In the following description, the droplet LD before adhering to the recording medium M is present in the state shown in FIG. 2A, that is, the pigment particles P are uniformly dispersed with respect to the solvent L. Suppose that. FIG. 2B illustrates a state in which the distribution of the pigment particles P becomes non-uniform with respect 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 uniformly dispersed with respect to the solvent L is defined as the particle diameter r, the pigment particles P uniformly distributed with respect to the solvent L However, when they aggregate with each other as shown in FIG. 2B, the apparent particle size of the pigment particles P increases from the particle diameter r to the particle diameter r ′. Further, due to the aggregation of the pigment particles P, the dispersed state of the pigment particles P with respect to the solvent L becomes non-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 the moving pigment particles P. 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 Equation 1, D is the mass diffusivity, η is the viscosity of the solvent L, T is the absolute temperature, k _B is the Boltzmann constant, and a is the particle radius. As shown in Equation 1, the larger the size of the pigment particles P, the smaller the diffusion coefficient D, and the smaller the degree of freedom of movement of the pigment particles P with respect to the solvent L. Therefore, when the pigment particles P are aggregated, the droplet LD becomes difficult to flow.

Generally, the droplet LD adhering to the recording medium M flows and spreads toward the periphery of the adhering portion. Therefore, when the droplet LD adheres on the recording medium M, the droplet LD comes into contact with the recording medium M. The size of the droplet LD becomes larger than that at the moment. However, when the droplet LD becomes difficult to flow due to the aggregation of the pigment particles P as described above, the size of the droplet LD adhering to the recording medium M also becomes difficult to change, and the liquid when the droplet LD adheres to the recording medium M becomes difficult to change. The size of the droplet LD is smaller than that when the droplet LD tends to flow. FIG. 1C is a diagram showing how the droplet LD permeates the recording medium M.

As shown in FIG. 1 (c), 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 particles P are the recording medium. It sticks to the surface of M. Then, the fixed droplet LD is dried and dots of the pigment particles P are formed.

FIG. 3 is a diagram showing an example of measured values obtained by measuring the surface of the recording medium M. In FIG. 3, the measured value of the shape of the surface of the recording medium M is represented by a light and shade image. This difference in shading is caused by fine irregularities in the recording medium M, for example, a difference in the structure near the surface of the recording medium M, a bias in the material of the recording medium M, and the like.

Such differences in structure near the surface of the recording medium M, material bias, and the like are referred to as surface characteristics of the recording medium M. Here, the surface characteristics of the recording medium M will be described in detail. FIG. 4A is a diagram showing a cross section of the recording medium M having a horizontal surface, and FIG. 4B is a diagram showing a cross section of the recording medium M having an uneven surface.

As shown in FIG. 4 (b), when the surface of the recording medium M has fine irregularities or the like, the contact angle of the recording medium M with respect to the surface changes even if the coagulant concentration 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 with respect to the recording medium M, that is, the difference in the behavior of the droplet LD with respect to the recording medium M, the recording medium depends on the size of the contact angle of the droplet LD with respect to the surface of the recording medium M. It is possible to evaluate the wettability, which is an index indicating the degree of adhesion of the droplet LD to M.

For example, it is evaluated that the smaller the contact angle of the droplet LD with respect to the recording medium M, the better the wettability. The better the wettability, the larger the contact area between the droplet LD and the recording medium M, and the faster the wettability and spread of the droplet LD with respect to the recording medium M. On the other hand, the poorer the wettability, the smaller the contact area between the droplet LD and the recording medium M, and the slower the wettability and spread of the droplet LD with respect to the recording medium M.

In the droplet LD with respect to the recording medium M shown in FIG. 4A, the wettability of the droplet LD is uniform with respect to the surface of the recording medium M. In such a case, the droplet LD forms a ball cap shape and adheres to the recording medium M. On the other hand, when the droplet LD comes into contact with the recording medium M having an uneven surface as shown in FIG. 4B, the area where the droplet LD contacts the recording medium M is small, and the area with respect to the recording medium M is small. Since the contact angle of the droplet LD becomes large, the wettability of the droplet LD deteriorates.

As described above, the area where the droplet LD comes into contact with the recording medium M also changes depending on the degree of unevenness of the recording medium M. Therefore, when 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 uneven, so that the shape of the dots formed on the recording medium M is not uniform. It disappears.

Further, the aggregating agent concentration AGC in the pretreatment agent layer PC affects the contact angle of the droplet LD with respect to the recording medium M, the rate at which the aggregating agent AG diffuses into the solvent L of the droplet LD, and the like. Therefore, since the contact area between the droplet LD and the recording medium M also changes depending on the coagulant concentration AGC of the pretreatment agent layer PC, the behavior of the droplet LD with respect to the recording medium M changes.

Due to such a change in the behavior of the droplet LD with respect to the recording medium M, the quality (image quality) of the image formed on the recording medium M by ejecting the droplet LD may deteriorate. For example, if dots of pigment particles P having a uniform shape cannot 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 deteriorates. ..

Therefore, in the present invention, the behavior of the droplet LD ejected to the recording medium M is controlled. At this time, by performing the pretreatment on the recording medium M, which is executed to control the behavior of the droplet LD, based on the surface characteristics of the recording medium M, the droplet LD is constant regardless of the position of the recording medium M. Allows you to control behavior. It is a gist of the present invention that this makes it possible to execute a higher quality image forming output.

Embodiment 1.
In the present embodiment, a line head type inkjet device in which a recording medium is conveyed and image formation output is performed by droplets ejected from a fixed ejection head will be described as an example.

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 conveys a DFE (Digital Front End) 1, an inkjet device 2, a pretreatment device 3, a measuring device 5A, 5B, and a roll paper Md as a recording medium M. It includes a carry-in section 17, a drying section 30, and a carry-out section 60 arranged along the direction Xm.

The DFE1 transmits instruction information to each part constituting the inkjet system 4, controls its operation, and executes an image forming output. Therefore, DFE1 functions as an image formation output control device. Further, DFE1 executes RIP (Raster Image Processor) processing based on the information of the image to be the image formation output, and generates raster data.

The DFE1 causes the inkjet device 2 and the preprocessing device 3 to execute image formation output using raster data, bitmap data input to the DFE1, and the like. Therefore, the bitmap data input to the DFE1 and the raster data generated by the DFE1 correspond to the drawing information referred to by the inkjet device 2 and the preprocessing device 3 when the image formation output is executed. As will be described later, this drawing information is a part of the image forming information that controls the operation of the preprocessing device 3 and controls the operation of the inkjet device 2.

The inkjet device 2 has four colorant discharge heads 21K, 21C, 21M, 21Y (hereinafter referred to as "colorant discharge head 21") of black (K), cyan (C), magenta (M), and yellow (Y). ) Is a droplet ejection device. In the following description, the color of the droplet LD ejected from the colorant ejection head 21 will be indicated by using the symbol shown in parentheses.

Further, in the present embodiment, a colored droplet such as an ink containing pigment particles P as a colorant will be described as a droplet LD. Therefore, the colorant ejection head 21 functions as a colored droplet ejection portion.

The pretreatment device 3 is a droplet ejection device including pretreatment agent ejection heads 31H and 31L, which are pretreatment execution units for ejecting the flocculant AG having a property of changing the dispersed state of the pigment particles P. The pretreatment agent discharge head 31H is a discharge head that discharges the pretreatment agent AGH as a droplet LD (first treatment droplet) having a high concentration of the coagulant AG, and functions as a first droplet discharge portion.

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

In the present embodiment, the recording medium M is a continuous paper wound in a roll shape (hereinafter referred to as “roll paper Md”). As the recording medium M, a continuous paper such as a continuous paper or a continuous form 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 cut paper cut to a predetermined size. Further, it may be a film instead of paper.

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

The measuring devices 5A and 5B measure, for example, a predetermined range of the roll paper Md (hereinafter referred to as "one band"), and generate a measurement image as shown in FIG. 3 based on the measured values. It should be noted that the measured image is generated with a quality that is at least larger than the resolution of the image formed and output. The predetermined range to be measured may be, for example, the smallest unit in which the processing executed by the pretreatment device 3 can be controlled in the predetermined range.

Further, the measuring devices 5A and 5B can be configured by a plurality of line sensors or area sensors, the measured amount per sensor can be reduced, and the measuring speed can be improved. The measuring device 5A is arranged 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 pre-output measurement image which is pre-output measurement information.

The measuring device 5B is arranged downstream of the inkjet device 2 with respect to the transport direction Xm, measures the recording medium M after the image formation output is performed, and generates a post-output measurement image which is post-output measurement information. Therefore, the measuring device 5A functions as a surface characteristic measuring unit for measuring the surface characteristics of the roll paper Md before the droplet LD is ejected. Further, the measuring device 5B measures the roll paper Md in which the dots of the pigment particles P are formed by the droplet LD.

The carry-in unit 17 has a paper feed unit 18 and a plurality of carry-in side transport rollers 19, and the roll paper Md in the paper feed unit 18 is carried into the pretreatment device 3 by using the carry-in side transport rollers 19. The pretreatment device 3 discharges the droplet LD containing the flocculant 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 ejects droplets containing a pigment or dye as a colorant onto the roll paper Md on which the pretreatment agent layer PC is formed to form 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 carry-out unit 60 carries out the roll paper Md on which the image is formed, and winds the roll paper Md on which the image is formed around the storage unit 61 by using the carry-out side transport roller 62.

When the roll paper Md is wound around the storage roll of the storage unit 61, if the pressure acting on the roll paper Md becomes large, the roll paper Md is stored in order to prevent other images from being transferred to the back surface of the roll paper Md. A drying mechanism for drying the roll paper Md may be provided immediately before winding up by the portion 61.

As described above, in the inkjet system 4 according to the present embodiment, the roll paper Md is conveyed to the pretreatment device 3 and the inkjet device 2 by the carry-in unit 17, and an image is formed 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 wound up by the carrying-out unit 60 so that the roll paper Md can be carried out to the outside of the inkjet system 4.

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

The pretreatment agent discharge heads 31H and 31L are arranged on the upstream side of the roll paper Md in the transport direction Xm, and the colorant discharge heads 21K, 21C, 21M and 21Y are arranged on the downstream side of the pretreatment agent discharge heads 31H and 31L. ing.

That is, the inkjet system 4 conveys the roll paper Md as a kind of medium that is an object for forming an image, and attaches a treatment agent to perform pretreatment for the image formation position on the upstream side of the transport direction Xm. Let me. The region where the treatment agent is attached to the roll paper Md is used as the treatment region, and the colorant is adhered to the treatment region to form an image (image).

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

The colorant discharge head 21K is a roll paper in 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 a direction orthogonal to the transport direction Xm of Md.

In the inkjet device 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 can be formed in the width direction of the region to be formed, that is, in the region orthogonal to the transport direction Xm of the roll paper Md.

Since the K, C, M, and Y colorant discharge heads 21 and the pretreatment agent discharge heads 31H and 31L each have the same configuration as the black (K) colorant discharge head 21K. , 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 21K has a flow path plate 41, a diaphragm 42, a nozzle plate 43, a frame member 44, and a pressure generating portion 45. The flow path plate 41 forms a passage for the droplet LD to be discharged. The flow path plate 41 is made of, for example, a single crystal silicon substrate having a crystal plane orientation (110).

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

The diaphragm 42 is made of, for example, a metal plate processed by nickel electroforming (for example, electroforming method, electroforming method, etc.). The diaphragm 42 may be a metal plate other than nickel, or a joining 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 internal direction of the colorant discharge head 21K. The diaphragm 42 is deformed by applying a force by the pressure generating portion 45.

The nozzle plate 43 is made of, for example, a single crystal silicon substrate. The nozzle plate 43 is processed by anisotropic etching in the same manner as the flow path plate 41. The nozzle plate 43 may have a structure in which a water-repellent layer is formed on an outer surface surface made 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, in the external direction of the colorant discharge head 21K.

Further, the nozzle plate 43 has a plurality of nozzles 40N for ejecting the droplet LD. Specifically, a nozzle 40N having a diameter of 10 to 30 μm is formed on the nozzle plate 43 corresponding to each liquid chamber 40F.

The frame member 44 is made of a thermosetting resin such as an epoxy resin or polyphenylene sulfide (PPS). In addition, a resin having the same characteristics may be used as the material of the frame member 44. The frame member 44 is provided with an accommodating portion 44I for accommodating the pressure generating portion 45, a recess serving as a common liquid chamber 40CR, and an ink supply port 40IN for supplying ink from the outside of the ejection head to the common liquid chamber 40CR, and is processed by injection molding. Has been done. The frame member 44 holds the peripheral edge of the diaphragm 42.

The pressure generating portion 45 has a piezoelectric element 45P, a base substrate 45B for joining and fixing the piezoelectric element 45P, and a strut portion arranged in a gap between adjacent piezoelectric elements 45P. Further, an FPC (Flexible Printed Circuits) cable 45C that connects the piezoelectric element 45P to the 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 faces of the piezoelectric element 45P.

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

As for the piezoelectric direction of the piezoelectric element 45P, when an electric field is applied to the crystal of the piezoelectric element 45P in parallel with the polarization direction, the ink in the liquid chamber 40F is added to the d31 mode in which the crystal becomes shorter. It may be pressed or depressurized. Further, the pressure generating unit 45 may arrange a row of piezoelectric elements for one nozzle 40N which is an ink ejection port.

The strut portion may be formed at the same time as 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 strut portion having a piezoelectric element 45P to which no voltage is applied as a member. Since the K, C, M, and Y colorant discharge heads 21 and the pretreatment agent discharge heads 31H and 31L each have the same configuration as the black (K) colorant discharge head 21K. , Duplicate explanations are omitted.

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

As shown in FIG. 8, the DFE1 instructs each part constituting the inkjet system 4 to operate and controls the operation. Then, the pretreatment device 3 executes the pretreatment for discharging the pretreatment agent PCA to the roll paper Md. Further, the inkjet device 2 ejects a droplet LD containing a colorant onto the pretreated roll paper Md to form an image.

Further, the measuring devices 5A and 5B each measure the roll paper Md and generate a measured image based on the measured value. The DFE1 and the inkjet device 2, the DFE1 and the pretreatment device 3, the DFE1 and the measuring devices 5A and 5B are communicably connected by signal lines 70LC, 71LC, 50ALC and 50BLC, respectively.

The print control unit 20Cc shown in FIG. 8 bends and deforms the diaphragm 42 by lowering the voltage applied to the piezoelectric element 45P from the reference potential and reducing the piezoelectric element 45P in the stacking direction. Then, the volume of the liquid chamber 40F is increased by the bending deformation of the diaphragm 42. As a result, the droplet LD flows from the common liquid chamber 40CR into the liquid chamber 40F.

Next, the print control unit 20Cc increases the voltage applied to the piezoelectric element 45P and extends the piezoelectric element 45P in the stacking direction to deform the diaphragm 42 in the nozzle 40N direction. Then, the volume of the liquid chamber 40F is reduced by the deformation of the diaphragm 42. As a result, pressure is applied to the droplet LD in the liquid chamber 40F, and the droplet LD is ejected from the nozzle 40N.

After that, the print control unit 20Cc returns the voltage applied to the piezoelectric element 45P to the reference potential, and executes an operation of restoring the diaphragm 42 to the position before the reference voltage is lowered, that is, the initial position. In the colorant discharge head 21K, the inside of 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. Next, the vibration of the meniscus of the nozzle 40N is attenuated, and then the operation proceeds to the next ejection operation of the droplet LD. In this way, the operation of ejecting 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. You can hit and so on. Since each discharge head of the colorant discharge head 21 of each color of K, C, M, and Y has the same configuration as the colorant discharge head 21K of black (K), overlapping description will be omitted.

Regarding the pretreatment agent ejection 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 print control unit 20Cc, and the droplet LD is relative to the roll paper Md. The pretreatment is executed by discharging.

The pressure generating unit 45 in the present embodiment is not limited to the piezoelectric element 45P, and for example, known techniques such as thermal type and electrostatic type can be adopted. The thermal type is a method in which a droplet LD in the liquid chamber 40F is heated by using a heat generation resistor to generate bubbles. The electrostatic type is a method in which a diaphragm and an electrode are arranged facing each other on 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 such colorant ejection heads 21K, 21C, 21M, 21Y and pretreatment agent ejection heads 31H, 31L in the width direction of a region where an 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 DFE1 according to this embodiment will be described. As shown in FIG. 9, the DFE1 has a CPU (Central Processing Unit) 11, a ROM (Read Only Memory) 12, and a RAM (Random Access Memory) 13. DFE1 further has an HDD (hard disk drive) 14, I / F15. Devices such as the CPU 11 constituting the DFE1 are connected to each other by a bus 16.

The inkjet device 2, the pretreatment device 3, and the measuring devices 5A and 5B are also composed of the same hardware as the DFE1. When the measuring devices 5A and 5B are image pickup devices such as a camera, the measuring devices 5A and 5B may have an image pickup unit such as a camera in addition to the configuration shown in FIG. 9, and the measuring devices 5A and 5B are infrared rays or ultrasonic waves. It may be configured to include a sensor for measuring the surface of the roll paper Md by such means.

The CPU 11 controls the operation of the entire DFE1. The CPU 11 controls the operation of the DFE1 by loading and executing the program stored in the ROM 12 or the HDD 14 into the RAM 13. A control program for controlling the CPU 11 is 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 / F15 is used for communication between the DFE1 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).

Further, the I / F15 may be configured to perform communication by, for example, PCI Express (Peripheral Component Interface Bus Express), ISA (Industry Standard Architecture), or the like. Further, the I / F 15 may be configured to have a plurality of channels corresponding to each color of the printed image data.

The DFE1 receives print job data transmitted from an external device such as a host device under the control of the CPU 11 via the I / F15 and stores the print job data in the HDD 14. DFE1 generates raster data, which is image information such as bitmap data corresponding to each CMYK color, based on job data received from a host device such as a PC (Personal Computer), and information including raster data (hereinafter referred to as "Raster data"). "Print output data") is transmitted to the inkjet device 2. The inkjet device 2 ejects the droplet LD to the roll paper Md based on the print output data.

Further, the DFE1 generates data for controlling the printing operation (hereinafter, referred to as "control information data") based on the print job data, the information input from the host device, and the like. The control information data includes print form, print type, feed / output information, print surface order, print paper size, print image data data size, resolution, paper type information, gradation, color information, and information on the number of pages to be printed. Contains data related to printing conditions such as.

Further, the control information data may include data related to the discharge of the post-treatment liquid discharged by the post-treatment device. The print output data is transmitted from DFE 1 to the inkjet device 2 and the preprocessing device 3, respectively.

Further, the DFE 1 transfers data (hereinafter referred to as “pre-processing output data”) regarding the ejection of the droplet LD ejected by the pre-processing device 3 to the pre-processing device 3 based on the pre-output measurement image generated by the measuring device 5A. Send.

Further, DFE1 analyzes the measurement image generated by the measuring device 5B, determines whether or not a desired dot is formed, and changes the ejection amount of the droplet LD in the preprocessing output data based on the determination result. And send it to the preprocessing device 3.

FIG. 10 is a block diagram showing a functional configuration of the inkjet device 2 and the pretreatment device 3 according to the present embodiment. The inkjet device 2 controls an operation of forming an image on the roll paper Md based on the print output data and the control information data input from the DFE1. 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, and 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 operation of the entire inkjet device 2 by using a control program stored in the ROM.

The print control unit 20Cc transmits / receives information such as commands, parameters, or data to and from the printer engine 20E based on the control information data transmitted from DFE1. 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 / receives control information data and the like to / from DFE1 via the signal line 20LC. The printer controller 20C transmits and receives control information data and the like to and from the printer engine 20E, which will be described later, via the signal line 20LC.

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

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

The printer engine 20E converts the bitmap data input from the DFE 1 to the inkjet device 2 into data corresponding to the image formation output based on the instruction from the printer controller 20C, and converts the colorant discharge head 21C and the colorant discharge head. The data is divided into 21M, a colorant discharge head 21Y, and a colorant discharge head 21K.

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

The pretreatment device 3 performs an operation of ejecting a droplet LD onto the roll paper Md based on the pretreatment output data and control information data input from DFE1 to form a pretreatment region which is a pretreated region. Execute. The pretreatment device 3 includes a precoat controller 30C and a precoat engine 30E.

The precoat controller 30C includes a CPU 30Cp and a pre-processing control unit 30Cc, and the CPU 30Cp and the pre-processing 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 operation of the entire preprocessing device 3 by using the control program stored in the ROM.

The preprocessing control unit 30Cc transmits / receives information such as commands, parameters, or data to and from the precoat engine 30E based on the control information data transmitted from DFE1. The pre-processing control unit 30Cc controls the pre-coat engine 30E by transmitting and receiving information to and from the pre-coat 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 DFE1 via the signal line 30LC. The precoat controller 30C transmits and receives control information data and the like to and from the precoat engine 30E, which will be described later, via the signal line 30LC.

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

The precoat engine 30E has pretreatment agent discharge control units 30Eph and 30Epl. Based on the instruction from the precoat controller 30C, the precoat engine 30E converts the bitmap data input from the DFE 1 to the pretreatment device 3 into small value data corresponding to the image formation output, and the pretreatment agent discharge control unit. Divide into data for each 30Eph and 30Epl.

For example, the precoat engine 30E converts the input 256-bit bitmap data into four values of large drop, medium drop, small drop, and no discharge, and converts it into data for each corresponding pretreatment agent discharge control unit 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 droplet LD on the roll paper Md based on the pretreatment output data transmitted from the pretreatment agent ejection control unit 30Cc, respectively. A pretreatment agent layer PC is formed on the roll paper Md.

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

The measuring device 5B includes a measuring control unit 50B. The measurement control unit 50B measures the surface of the roll paper Md over a predetermined range in the width direction and the transport direction Xm based on the measurement execution information transmitted from DFE1. Then, a measurement image is generated based on the measured value, and the generated measurement image is transmitted to DFE1.

As described above, in the inkjet system 4 according to the present embodiment, the inkjet device 2 ejects droplets onto the roll paper Md pretreated by the pretreatment device 3 based on the drawing information input from the DFE 1. By doing so, the image formation output is executed. Next, the functional configuration of DFE1 according to this embodiment will be described with reference to FIG.

As shown in FIG. 11, DFE1 includes a controller 100, an input / output device 400, and a network I / F15F. The input / output device 400 is an output interface that visually displays the state of the DFE1, and is also an input interface when the user directly operates the DFE1 as a touch panel or inputs information to the DFE1.

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 / F15F is an interface for DFE1 to communicate with other devices such as a host terminal and measuring devices 5A and 5B via a network, and an Ethernet (registered trademark) or USB (Universal Serial Bus) interface is used. The network I / F15F can communicate by the TCP / IP protocol. The network I / F15F is realized by the I / F15.

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 composed of a combination of hardware and software shown in FIG. Specifically, a program stored in a ROM 12, a non-volatile memory, and a non-volatile storage medium such as an HDD 14 or an optical disk is loaded into a volatile memory (hereinafter, memory) such as a RAM 13.

The CPU 11 performs an operation according to a program loaded in the RAM 13 or the like. The controller 100 is composed of a software control unit configured by these series of collaborations and hardware such as an integrated circuit. The controller 100 functions as a control unit that controls the entire DFE1.

The main control unit 110 plays a role of controlling each unit included in the controller 100, and gives a command to each unit of the controller 100. The engine control unit 120 plays a role as a drive means for controlling or driving the inkjet device 2, the pretreatment device 3, the carry-in unit 17, the carry-out 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 according to the control of the main control unit 110. This drawing information is information for drawing an image to be formed in the image forming operation by the inkjet device 2 and the preprocessing device 3, that is, an image to be output for 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 the information input via the input / output device 400. The input / output control unit 150 inputs information input via the network I / F 15F to the main control unit 110. Further, the main control unit 110 controls the input / output control unit 150 to access the network I / F15F and other devices connected to the network via the network.

As a process executed by DFE1, first, the input / output control unit 150 receives a print job which is instruction information for executing image formation output from a host device or the like via the network I / F15F. The input / output control unit 150 transfers the received print job to the main control unit 110. When the main control unit 110 receives the print job, the main control unit 110 controls the image processing unit 130 to generate drawing information based on the document information included in the print job or the image information.

In the print job according to the present embodiment, in addition to the image information in which the image information to be output is described in an information format that can be analyzed by the image processing unit 130 of DFE1, the information of the parameters to be set at the time of image formation output is displayed. included. The information of this parameter is, for example, information such as double-sided printing setting, aggregate printing setting, and color / monochrome setting.

When the 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 engine control unit 120 transmits the print output data and the preprocessing output data. Image formation is performed on the paper transported from the carry-in 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, the functional configuration of the main control unit 110, which also functions as the preprocessing 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 pretreatment 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 shows the discharge amount of the pretreatment agent PCA and the coagulant concentration AGC regarding the size of the dots 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 shows the medium characteristics of the recording medium M (for example, high or low permeability), the type of the pigment particles P contained in the droplet LD, and the pretreatment agent PCA. It is configured for each type combination.

FIG. 13 shows the relationship between the discharge amount of the pretreatment agent PCAa in the low-permeability recording medium M, the coagulant concentration AGC, and the dot size of the pigment Dy, and FIG. 14 shows the pretreatment agent in the medium-permeability recording medium M. Relationship between the discharge amount of PCAa and the coagulant concentration AGC and the size of the dots of the pigment Dy. FIG. 15 shows the discharge amount of the pretreatment agent PCAa and the coagulant concentration AGC and the dots of the pigment Dy in the highly permeable recording medium M. It is a figure which illustrated the characteristic information data table SD which shows the relationship with the size, respectively.

As shown in FIGS. 13 to 15, when the pretreatment agent layer PC is formed on the recording medium M and then the droplet LD is ejected to form an image, the pigment particles P contained in the droplet LD form the image. The dots to be formed become larger as the discharge amount of the pretreatment agent PCA is larger, and become larger as the concentration of the coagulant AG is higher. 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 increase or decrease the speed at which the droplet LD, which is an image forming agent and contains the pigment particles P as a colorant, wets and spreads.

As described above, the characteristic information data table SD contains 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. Information configured as a relationship with is included as characteristic information.

Further, the characteristic information data table SD shows 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 a relationship may be input as a result of the image formation output, or may be configured by the characteristic information obtained as a result of an experiment or a simulation.

Further, the characteristic information data table SD may be configured by the characteristic information obtained as a simulation result or an experimental result showing the relationship between the discharge amount of the pretreatment agent PCA and the coagulant concentration AGC for each type of the recording medium M. .. 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 the 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 an permeable medium, and is information indicating the degree of penetration of the droplet LD into the recording medium M. be.

As a non-permeable medium, a film is known, and as a permeable medium, plain paper or coated paper is known. Further, as the medium characteristic information, the surface roughness of the surface of the recording medium M may be measured 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 contains information on the characteristics of the pretreatment agent PCA1 discharged from the pretreatment agent discharge head 31H and the pretreatment agent PCA2 discharged from the pretreatment agent discharge head 31L. Information is stored. The pretreatment agent property information is, for example, information indicating the material and physical properties of the pretreatment agent PCA.

The colorant characteristic information storage unit 116 stores colorant characteristic information, which is information on the characteristics of each ink of YMCK ejected from the colorant ejection head 21. The colorant characteristic information is, for example, information indicating the material and physical characteristics of the colorant that colors each color of YMCK.

The main control unit 110 may be configured to add characteristic information to the characteristic information data table SD by referring to the pretreatment 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 characteristics of the recording medium M for each pixel with respect to the pre-output measurement image input to the main control unit 110 via the input / output control unit 150, and outputs the analysis result. ..

The measurement information analysis unit 112, for example, is based on a relational expression representing the relationship between the shading value and the surface characteristics of the measured image on the surface of the recording medium M shown in FIGS. 16 and 17, and the recording medium M is used for each pixel of the measurement image. The analysis result of the surface characteristics of is output. The analysis result of the surface characteristics of the recording medium M does not have to be for each pixel, and may be output for each predetermined region according to the ejection resolution of the droplet, for example.

FIG. 16 is a diagram schematically showing the relationship between the shading value of the measured image on the surface of the recording medium M and the wettability of the droplet LD with respect to the recording medium M, and FIG. 17 is the measurement of the surface of the recording medium M. It is a figure which simplifies the relational expression which expresses the relationship between the shading value of an image, and the permeability of a droplet LD with respect to a recording medium M.

In FIG. 16, it is shown that the darker the shade of the measured image on the surface of the recording medium M, the better the wettability of the droplet LD with respect to the recording medium M, and the more easily the droplet LD adheres to the recording medium M. In FIG. 17, it is shown that the darker the shade of the measured image on the surface of the recording medium M, the greater the permeability of the droplet LD to the recording medium M, and the easier it is for the droplet LD to penetrate into 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 shading information for each pixel of the measurement image, and transmits the analysis result to the pretreatment agent discharge amount calculation unit 113. Further, the measurement information analysis unit 112 analyzes the permeability of the droplet LD to the recording medium M based on the information on the shading of each pixel of the measurement image, and transmits the analysis result to the pretreatment agent discharge amount calculation unit 113. ..

The pretreatment agent discharge amount calculation unit 113 is used from the pretreatment agent discharge heads 31H and 31L, respectively, based on the analysis result of the measurement image by the measurement information analysis unit 112 and various characteristic information stored in the characteristic information storage unit 111. It functions as a processed droplet ejection amount calculation unit, a first droplet ejection amount calculation unit, and a second droplet ejection amount calculation unit for calculating the amount of the pretreatment agent which is the processed droplet ejection amount to be ejected.

Then, the pretreatment agent PCA is discharged to the recording medium M based on the discharge amount of the pretreatment agent PCA calculated by the pretreatment agent discharge amount calculation unit 113 to form the pretreatment agent layer PC, thereby forming the recording medium. It controls the behavior of the droplet LD containing the image forming agent on the M surface.

Next, the difference in the formation mode of the pretreatment agent layer PC with respect to the recording medium M will be described with reference to FIG. First, when the pretreatment agent PCA is discharged to 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 and the coagulant concentration AGC discharged with respect to the region (a) and the region (b) are the same, and the region shown by (a) and the region shown by (b) are the same. In the description, it is assumed that the penetrance of the droplet LD with respect to the recording medium M is different.

At this time, the penetrance of the droplet LD with respect to the recording medium M is different between the region shown in FIG. 18A and the region shown in FIG. 18B. Specifically, in the region shown in (b), the coagulant AG is likely to move in the thickness direction of the recording medium M because the coagulant AG is smaller than the voids of the recording medium M.

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

Compared with the distribution mode of the flocculant AG in the region (a), in the region (b), the flocculant AG diffuses in the thickness direction of the recording medium M and is larger in the thickness direction of the recording medium M. A pretreatment agent layer PC is formed in the range. Therefore, in the pretreatment agent layer PC formed in the region (b), the concentration of the flocculant AG is lower than that in the pretreatment agent layer PC formed in the region (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). Further, in the region (b), since the flocculant AG is distributed at a position far from the surface of the recording medium M, the amount of the flocculant AG diffused into the droplet LD adhering to the recording medium M per unit time is , It is less than the region of (a).

On the other hand, in the region (a), since the flocculant AG is distributed at a position close to the surface of the recording medium M, the amount of the flocculant AG diffused into the droplet LD adhering to the recording medium M per unit time. Is larger than that of the region (b).

Therefore, if the droplet LD is ejected to each of the regions (a) and (b), the amount of the flocculant AG diffused in the droplet LD ejected to each region is different. As a result, the behavior of the ejected droplet LD also differs, and the size of the dots formed by the pigment particles P also differs.

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 so that the desired dots are formed by the image forming agent. The execution mode of the pretreatment is controlled based on the surface characteristics of the above. Specifically, the main control unit 110 controls the discharge amounts of the pretreatment agent PCA1 and the pretreatment agent PCA2 having different coagulant concentration AGCs based on the surface characteristics of the recording medium M to form the pretreatment agent layer PC.

Specifically, the region shown in FIG. 19A is a region analyzed by the measurement information analysis unit 112 that the permeability of the droplet LD to the recording medium M is low. Further, the region shown in FIG. 19B is a region 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 pretreatment agent discharge amount calculation unit 113 so that the amount of the coagulant AG per unit time diffused into the droplet LD adhering to the region shown in (a) and the region shown in (b) becomes the same. The discharge amounts of the pretreatment agent PCA1 and the pretreatment agent PCA2 are calculated. By doing so, the pretreatment device 3 can perform pretreatment on the recording medium M so 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 necessarily formed on the recording medium M so that the surface of the recording medium M is horizontal. And it is not necessary to discharge the pretreatment agent PCA2 to form the pretreatment agent layer PC.

In this way, 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 transmitted 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 discharge head 31H for discharging the pretreatment agent PCA1 having a high concentration of the coagulant AG and the pretreatment agent PCA2 for discharging the pretreatment agent PCA2 having a low concentration of the coagulant AG. Includes head 31L. Then, in the pretreatment device 3, from each of the pretreatment agent discharge head 31H and the pretreatment agent discharge head 31L, as shown in FIG. 20, the pretreatment agent PCA1 having a high concentration of the coagulant AG with respect to the recording medium M The pretreatment agent PCA2 having a low concentration of the flocculant 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 the droplet LD, which is an image forming agent containing the pigment particles P, is ejected to the pretreatment agent layer PC shown in FIG. 20.

At this time, as shown in FIG. 19, the pretreatment agent layer PC1 has a low concentration of the flocculant AG, and the pretreatment agent layer PC is formed near the surface of the recording medium M. On the other hand, the pretreatment agent layer PC2 has a high concentration of the flocculant AG, and the pretreatment agent layer PC is formed so as to expand in the thickness direction of the recording medium M as compared with the pretreatment agent layer PC1.

At this time, since the amount of the flocculant AG per unit time diffused with respect to the droplet 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 Dots of the same size are formed by the droplet LDs attached to the agent layer PC2.

As described above, in the inkjet system 4 according to the present embodiment, the behavior of the droplet LD containing the colorant on the recording medium M depends on the concentration of the flocculant AG in the pretreatment agent layer PC formed on the recording medium M. And controls the size of dots and the shape of dots, which are colored regions formed by the droplet LD adhering to the recording medium M.

The pretreatment agent discharge amount calculation unit 113 discharges the pretreatment agents PCA1 and PCA2 from the pretreatment agent discharge head 31H and the pretreatment agent discharge head 31L to the same region on the recording medium M, respectively. In addition, the configuration may be such that the first treated droplet discharge amount and the second treated droplet discharge amount, which are the discharge amounts of the pretreatment agents PCA1 and PCA2, are calculated. At this time, the pretreatment device 3 controls the discharge timing of the pretreatment agent discharge head 31H and the pretreatment agent discharge head 31L, and discharges the pretreatment agent PCA1 and the pretreatment agent PCA2 to the same region to discharge the pretreatment agent PCA1 and the pretreatment agent PCA2. 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.

Based on the job data, the image processing unit 130 sets the print conditions specified in the job data for the image information, executes the RIP (Raster Image Processing) process, and executes the image formation output. Generate drawing information such as data (S2102).

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

The image processing unit 130 transmits the drawing information and the setting information generated by the RIP processing to the main control unit 110 (S2103). Upon receiving 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 a measurement image for one band as a measurement result (S2104), and measures the measurement. It is transmitted to the information analysis unit 112.

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

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

The pretreatment agent discharge amount calculation unit 113 preprocesses each pixel obtained from the analysis result based on the characteristic information acquired in S2106 and the analysis result of the surface characteristics 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). As a result, when different analysis results are obtained depending on the position of the surface of the recording medium M, the execution mode of the pretreatment is changed according to the position of the recording medium M according to the droplet LD ejected to the recording medium M.

In the treatment of S2107, the discharge amount of either the pretreatment agent PCA1 or the pretreatment agent PCA2 may be set to "0" to calculate the discharge amount of the pretreatment agents PCA1 and PCA2. The calculated pretreatment agent amount information, which is the information on the discharge amounts of the pretreatment agents PCA1 and PCA2, is transmitted to the pretreatment 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, the flow of processing for performing image formation output will be described. The main control unit 110 transmits preprocessing execution information for causing the preprocessing device 3 to execute the preprocessing.

When the pretreatment apparatus 3 receives the pretreatment execution information from the DFE1, the pretreatment agent PCA1 and the pretreatment agent PCA2 are discharged to the recording medium M based on the pretreatment agent amount information received from the DFE1 in S2108. Perform preprocessing.

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

The position measured by the measuring device 5A, the position where the pretreatment device 3 performs the pretreatment, and the position where the colorant discharge head 21 discharges are managed as the transport positions of the recording medium M, respectively, and are instructed by the main control unit 110. An image is formed on the recording medium M by the measuring device 5A, the pretreatment device 3, and the colorant ejection head 21 operating in synchronization with each other.

Therefore, the main control unit 110 functions as a droplet ejection control unit that ejects droplets to the inkjet device 2 and the pretreatment device 3. Further, the main control unit 110 discharges the processed droplets such as the pretreatment agent PCA to the pretreatment apparatus 3, the processing droplet ejection execution control unit, and the coloring droplets containing the colorant to be ejected to the inkjet apparatus 2. It also functions as a droplet ejection execution control unit. The recording medium M on which the image is formed is discharged from the carry-out unit 60.

As described above, in the present embodiment, the behavior of the ejected droplet LD is controlled by forming the pretreatment agent layer PC based on the surface characteristics of the recording medium M, and the pigment contained in the droplet LD is contained. The shape of the dots formed by the particles P is made to have 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. However, the pretreatment agent PCA1 and the pretreatment agent PCA2 may be discharged into the same region to form the pretreatment agent layer PC. By doing so, the flocculant concentration AGC in the pretreatment agent layer PC can be controlled more finely.

From the above, in the present embodiment, when pretreatment is performed on a medium whose surface shape is not constant in the thickness direction, such as plain paper, coated paper, and wood, and then ink is ejected, the medium is used. 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, a uniform ink shape can be formed on the medium.

Further, since it is possible to form a pretreatment region having wettability and permeability according to the ink at each position of the medium according to the information of the ink ejected to the medium and the surface characteristics of the medium, a high quality image is formed. Can be executed.

In addition to the pigment particles P, biomolecules such as dyes, proteins, lipids, nucleic acids, hormones, sugars, and amino acids are contained in the droplet LD ejected from the inkjet device 2 and the pretreatment device 3 to the recording medium M. , Resin, polymer and the like may be used. Further, as the reactant contained in the pretreatment agent PCA, a chelating agent, a fibrin-based adhesive, hydroxyapatite, a polymerizing agent and the like may be used in addition to the flocculant AG.

Further, the inkjet system 4 according to the present embodiment can also be applied to a three-dimensional modeling device such as a 3D printer.

The measuring device 5A may be provided with the same function as the measurement information analysis unit 112, and the measuring device 5A and the measuring device 5B may be made to analyze the measurement image before output. Then, the measuring device 5A transmits the analysis result of the measurement image before output to DFE1.

In such a case, the pretreatment agent discharge amount calculation unit 113 calculates the discharge amount of the pretreatment agent PCA based on the surface characteristics of the recording medium M transmitted from the measuring device 5A to the DFE1.

Embodiment 2.
In the present embodiment, a serial head type inkjet device that conveys a recording medium and executes image forming output by droplets ejected from a ejection head moving in the main scanning direction will be described as an example. The same components as those in the first embodiment are designated by the same reference numerals, and duplicate description will be omitted.

FIG. 22 is a diagram showing an outline of the inkjet 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 preprocessing apparatus 3 of the first embodiment in one housing.

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. The image forming apparatus 6 includes an inkjet device 2, a preprocessing device 3, measuring devices 5A, 5B, and a carriage 101 that moves the inkjet device 2 and the preprocessing device 3 in the main scanning direction inside the device main body.

The carriage 101 is slidably arranged in the main scanning direction (direction perpendicular to the transport direction Xm) by the main guide rod 107 and the slave guide rod 107b, which are guide members laid horizontally on the left and right side plates. .. The carriage 101 is equipped with an inkjet device 2 and a preprocessing device 3. Further, a measuring device 5A is mounted on the side surface of the carriage 101 on the preprocessing device 3 side, and a measuring device 5B is mounted on the side surface of the carriage 101 on the inkjet device 2 side.

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

The cartridge 103 that supplies the droplet LD containing the colorants of each color to the colorant discharge head 21 and the droplet LD containing the pretreatment agent PCA to the pretreatment agent discharge head 31 is provided on the carriage 101 so as to be replaceable. It is installed. Further, the cartridge 103 has an atmospheric port communicating with the atmosphere above, and a supply port below which supplies the droplet LD to the colorant discharge head 21 or the pretreatment agent discharge head 31. 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 this embodiment, the case where the colorant ejection head 21 is provided for each color is taken as an example, but one head having a nozzle 40N for ejecting the droplet LD of each color of YMCK may be used.

Further, although the pretreatment agent ejection head 31 is also provided for each concentration of the flocculant AG as an example, one head having a nozzle 40N for ejecting droplet LDs of the flocculant AG having different concentrations may be used. ..

The carriage 101 is slidably mounted on the main guide rod 107 on the rear side (downstream side in the paper transport direction) and slidably mounted on the slave guide rod 107b on the front side (upstream side in the paper transport direction). A timing belt 212 is laid between the drive pulley 210 and the driven pulley 211, which are rotationally driven by the main scanning motor 109, in order to move and scan the carriage 101 in the main scanning direction. The timing belt 212 and the carriage 101 are fixed, and the carriage 101 is reciprocated and driven by the forward and reverse rotation of the main scanning motor 109.

On the other hand, in order to convey the recording medium M stacked on the paper feed cassette 204 to the lower side of the inkjet head 102, the paper feed roller 213 and the friction pad 214 for separately supplying the recording medium M from the paper feed cassette 204, and recording. The guide member 215 that guides the medium M, the transport roller 216 that reverses and transports the transported recording medium M, and the transport roller 118a and the transport roller 216 that are pressed against the peripheral surface of the transport roller 216 send out the recording medium M. A tip roller 118b that defines the angle is provided. The transfer roller 216 is rotationally driven via a gear train by a sub-scanning motor.

Imprinting, which is a guide member that guides the recording medium M sent out from the transport roller 216 corresponding to the range in the main scanning direction in which the carriage 101 moves, on the lower side of the colorant discharge head 21 and the pretreatment agent discharge head 31. A receiving member 119 is provided.

On the downstream side in the direction in which the recording medium M is conveyed to the imprint receiving member 119, the recording medium M is rotationally driven to be sent out in the direction of being discharged to the outside of the housing of the image forming apparatus 6. A transport roller 220 and a spur 121 are provided. Further, a paper ejection roller 122 and a spur 123 for feeding the recording medium M to the paper ejection tray 106, and guide members 124 and 125 forming a path for ejecting the recording medium M to the outside of the housing of the image forming apparatus 6 are arranged. ing.

Next, with reference to FIG. 25, the functional configuration of the image forming apparatus 6 according to the present embodiment will be described. The image forming apparatus 6 according to the present embodiment is configured by adding a transfer control unit 60C for controlling the transfer of the recording medium M to the functions of the inkjet device 2 and the preprocessing device 3 shown in FIG.

The transport control unit 60C drives the sub-scanning motor based on the command information received from the print control unit 20Cc and the preprocessing control unit 30Cc to transport the recording medium M. The print control unit 20Cc and the pretreatment control unit 30Cc also function as a drive control unit that controls the drive of the main scanning motor 109. Since other configurations are the same as those in FIG. 9, duplicate description will be omitted.

In this embodiment, the inkjet device 2 and the pretreatment device 3 are integrated into one housing to form the image forming device 6. Therefore, each unit of the image forming apparatus 6 may be controlled based on the information received from the main control unit 110 by the image forming controller which is a control unit for controlling 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. .. Further, at this time, the main control unit 110 functions as a droplet ejection control unit for ejecting droplets to the image forming apparatus 6.

Using the image forming apparatus 6 configured as described above, the inkjet system 4 according to the present embodiment executes image forming output based on image information. 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. 26.

When the DFE1 completes the process shown in the flowchart of FIG. 21, the main control unit 110 transmits preprocess execution information for causing the preprocessing device 3 to execute the preprocess (S2601). The pretreatment device 3 discharges the pretreatment agent PCA1 and the pretreatment agent PCA2 to the recording medium M based on the pretreatment execution information received from DFE1 to execute the pretreatment.

When the pretreatment agent discharge heads 31H and 31L discharge the droplet LD to the recording medium M, the pretreatment control unit 30Cc drives the pretreatment agent discharge heads 31H and 31L based on the drawing information while moving the carriage 101. , The droplet LD containing the pretreatment agent PCA is ejected to the stopped recording medium M by one band in the main scanning direction (S2602). When the ejection for one band is completed, the preprocessing device 3 transmits a preprocessing completion notification for executing the preprocessing for one band to DFE1 (S2603).

Upon receiving the preprocessing completion notification from the preprocessing device 3, the DFE 1 transmits the transfer 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 drives the sub-scanning motor to the transport control unit 60C according to the transport execution information, transports the recording medium M by the transport roller 216 for one band in the sub-scanning direction (S2605), and sends the transport completion notification to DFE1. Transmit (S2606).

Upon receiving the transfer execution notification, the DFE 1 transmits image formation execution information for causing the inkjet device 2 to execute an image formation output for one band (S2607). When the colorant ejection head 21 ejects the droplet LD to the recording medium M, the print control unit 20Cc drives the colorant ejection head 21 of each color based on the drawing information while moving the carriage 101, and stops. Droplets LD containing colorants of each color are ejected to the recording medium M for one band in the main scanning direction (S2608).

When the ejection for one band is completed, the inkjet device 2 drives the sub-scanning motor to the print control unit 20Cc to convey the recording medium M, and transmits an image formation completion notification to the DFE1 (S2609).

The DFE1 transmits the discharge execution information for discharging the recording medium M to the image forming apparatus 6 when all the image forming outputs of the drawing information included in the job data are completed (S2610), and drives the sub-scanning motor to drive the image. The recording medium M on which the above 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, DFE1 is re-executed from the process of S2101.

Embodiment 3.
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. Further, the same components as those in the first embodiment are designated by the same reference numerals, and duplicate description will be omitted.

The inkjet system 4 according to the present embodiment is configured in the same manner as the inkjet system 4 shown 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 has a configuration in which the feedback control unit 117 is added to the configuration shown in FIG.

The feedback control unit 117 determines whether or not a desired dot is formed in the recording medium M based on the post-output measurement image and the drawing information, which are the measurement information after the image formation output acquired from the measuring device 5B. Functions as a shape comparison unit. Then, based on the determination result, the feedback control unit 117 functions as a feedback control unit that performs feedback control for correcting 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 between the measured image after output and the drawing information, and determines how much the difference has occurred. At this time, when the image to be output is a line or a surface or a dot formed by overlapping the pigment particles P of multiple colors, the feedback control unit 117 changes the shape of a single dot. Cannot be detected.

In such a case, the feedback control unit 117 compares the dot size, area, etc. only in the pixels to which the dot size, area, etc. can be compared in the image formed and output, and how much difference occurs. It may be determined whether or not.

Further, the determination of whether or not a desired dot is formed in the recording medium M performed by the feedback control unit 117 does not need to be continuously executed during the image formation output operation, for example, every morning or every 6 hours. It may be configured to be executed periodically.

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

The feedback control unit 117 compares the size and area of dots between the measured image after output and the drawing information, and when it is determined that a difference of a predetermined value or more has occurred, the characteristic information shown in FIGS. 13 to 15. The discharge amount of the pretreatment agent PCA calculated by the pretreatment agent discharge amount calculation unit 113 based on the value of the data table SD is controlled.

Specifically, when the size or area of the dots in the post-output measurement image is larger than the size or area of the dots in the drawing information, the feedback control unit 117 has a concentration lower than the coagulant concentration AGC of the pretreatment agent PCA2 up to that point. The pretreatment agent PCA1 containing the flocculant AG of the above is used. Alternatively, feedback control is executed so as to reduce the discharge amount of the pretreatment agent PCA2.

Further, at this time, since the size of the dots becomes smaller in the region where the permeability of the recording medium M is high, feedback control is performed so that the dots become larger, and in the region where the permeability of the recording medium M is low, the size of the dots becomes smaller. Since 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 this embodiment will be described with reference to FIG. 28. A predetermined time has elapsed from the execution of the previous image formation output, or the user of the inkjet system 4 performs an operation instructing the execution of the feedback control from the input / output device 400, so that the main control unit 110 is instructed to execute the feedback. Information is input (S2801).

When the 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 measured image after output with the drawing information, and determines whether or not a desired dot is formed in the recording medium M based on the comparison result (S2803).

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

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

The measuring device 5B may be provided with the same function as the feedback control unit 117, and the measuring device 5B may be made to analyze the measured image after output. Then, the measuring device 5B transmits the analysis result of the measured image after output to DFE1.

In such a case, the feedback control unit 117 of the DFE1 executes feedback control for 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 DFE1 described above may be a dedicated device, or may be realized by installing predetermined software on a server device or a personal computer.

Further, the DFE1 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 the DFE 1, the function of giving an instruction to the preprocessing device 3 based on the output of the measurement control unit 50A may be realized by the controller in the preprocessing device 3. Further, the function of DFE1 may be realized by collaborating with the DFE1, the controller in the inkjet device 2, and the controller in the preprocessing device 3.

Further, although the recording medium M is conveyed in the above-described embodiment, the recording medium M may not be conveyed. For example, a flatbed system in which a recording medium M is arranged on a table and a carriage on which a colorant discharge head 21 and a pretreatment agent discharge head 31 are mounted moves in a two-dimensional direction to form an image on the recording medium M. It can also be applied to inkjet devices.

Further, although the above-mentioned pretreatment device 3 has been described with the example of the device for discharging the pretreatment liquid, it may be another device for performing pretreatment. 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 refers 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
2 Inkjet equipment 3 Pretreatment equipment 4 Inkjet system 5A, 5B measuring equipment 6 Image forming equipment 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 Part 116 Colorant characteristic information storage unit 117 Feedback control unit SD characteristic information data table

Japanese Unexamined Patent Publication No. 2015-189110

Claims (7)

A surface characteristic measuring unit that measures the surface characteristics of the medium,
Prior to the treatment of ejecting the droplets containing the colorant into the medium, a pretreatment of applying a treatment agent having a property of aggregating the particles of the colorant to the medium to form a pretreatment agent layer is applied to the medium. Pre-processing execution part to be performed and
A pretreatment execution control unit that controls an execution mode of the pretreatment for each position of the medium based on the surface characteristics.
Including
The pretreatment execution unit is
As the pretreatment, a process for controlling the behavior of the droplets by changing the dispersed state of the colorant contained in the droplets ejected onto the medium is executed on the medium.
The pre-processing execution control unit
The execution mode of the pretreatment is controlled for each position of the medium so that the behavior of the droplets ejected on the medium becomes constant .
A pretreatment device characterized by that. The pretreatment execution unit is
It is characterized in that a pretreatment agent that changes the dispersed state of the colorant contained in the droplets discharged onto the medium is discharged to the medium.
The pretreatment apparatus according to claim 1 . A surface characteristic measuring unit that measures the surface characteristics of the medium,
Prior to the treatment of ejecting the droplets containing the colorant into the medium, a pretreatment of applying a treatment agent having a property of aggregating the particles of the colorant to the medium to form a pretreatment agent layer is applied to the medium. Pre-processing execution part to be performed and
A pretreatment execution control unit that controls an execution mode of the pretreatment for each position of the medium based on the surface characteristics.
Including
The pre-processing execution control unit
The execution mode of the pretreatment relating to the wetting and spreading speed of the droplets ejected on the medium is controlled so that the behavior of the droplets ejected on the medium is constant for each position of the medium . ,
A pretreatment device characterized by that. The pre-processing execution control unit
One of claims 1 to 3 , wherein the execution mode of the pretreatment is controlled for each position of the medium based on the information of the droplets ejected on the medium and the surface characteristics. The pretreatment device described in. The pretreatment execution unit is
The pretreatment according to any one of claims 1 to 4 , wherein a plasma treatment is performed on the medium to change the dispersed state of the colorant contained in the droplets ejected on the medium. Device. The pretreatment apparatus according to any one of claims 1 to 5 .
A droplet ejection device that ejects droplets onto a medium to perform image formation output,
An inkjet system characterized by including. This is a pretreatment method for performing a pretreatment for forming a pretreatment agent layer by applying a treatment agent for aggregating the particles of the colorant onto the medium before the treatment for ejecting the droplets containing the colorant onto the medium. hand,
Measure the surface properties of the medium and
In controlling the execution mode of the pretreatment for each position of the medium based on the surface characteristics when the pretreatment is performed on the medium.
As the pretreatment, a process of changing the dispersed state of the colorant contained in the droplets for each position of the medium is executed so that the behavior of the droplets ejected on the medium becomes constant .
A pretreatment method characterized by that.

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