Image formation apparatus, method for examining discharge of transparent droplets, and program for examining discharge of transparent droplets

The present application is based on and claims the benefit of priorities of Japanese Priority Application No. 2014-185659 filed on Sep. 11, 2014 and Japanese Priority Application No. 2015-139226 filed on Jul. 10, 2015, the entire contents of which are hereby incorporated by reference.

1. Field of the Invention

The present invention relates to an image formation apparatus, a method for examining a discharge of transparent droplets, and a program for examining the discharge of transparent droplets.

2. Description of the Related Art

It is difficult to visually observe patterns formed with transparent droplets unlike patterns formed with color ink droplets.

Some documents describe a technique of performing registration adjustment through detection of recording positions of transparent droplets by a detection unit based on the fact that if transparent droplets are placed on color ink when printing is performed, color is different from a case where printing is performed with only the color ink (see Patent Documents 1 and 2, for example).

However, it is difficult to visually detect nozzle clogging or a curved discharge from multiple patterns formed with transparent droplets discharged from multiple nozzles.

[Patent Document 1] Japanese Laid-Open Patent Application No. 2012-035446 [Patent Document 2] Japanese Laid-Open Patent Application No. 2000-141624

It is a general object of at least one embodiment of the present invention to provide an image formation apparatus capable of improving visibility of patterns formed with transparent droplets discharged from multiple nozzles.

In an embodiment, an image formation apparatus is provided. The image formation apparatus includes a first discharge unit including a first nozzle line having a plurality of nozzles, the first nozzle line discharging color droplets to form a predetermined image on a recording medium, the first discharge unit moving relative to the recording medium; and a second discharge unit including a second nozzle line that discharges transparent droplets on the recording medium on which the predetermined image is formed, the second discharge unit moving in a first direction relative to the recording medium, and the second nozzle line having a plurality of nozzles arranged in a second direction orthogonal to the first direction. When a discharge operation of the second discharge unit is examined, after the predetermined image is formed with the color droplets discharged by the first discharge unit, the second discharge unit discharges the transparent droplets from two or more of the nozzles thereof spaced at m−1 nozzle intervals in the second direction to form a row of dots extending in the second direction, and repeats forming the rows while successively moving in the first direction relative to the recording medium so as to form m rows arranged side by side in the first direction, positions of the discharging nozzles being successively shifted together by one nozzle in the second direction upon a successive movement of the second discharge unit relative to the recording medium in the first direction, such that the dots in each of the rows are formed at m−1 nozzle intervals, and positions of the dots in an n-th one of the rows are displaced together by one nozzle in the second direction relative to positions of the dots in an n−1-th one of the rows.

According to an embodiment, it is possible to improve visibility of patterns formed with transparent droplets discharged from multiple nozzles.

Other objects and further features of embodiments will become apparent from the following detailed description when read in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic side view showing an image formation apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic configuration diagram showing a pretreatment unit of the image formation apparatus of FIG. 1 ;

FIG. 3 is a schematic configuration diagram illustrating a drying unit of the image formation apparatus of FIG. 1 ;

FIG. 4A is a diagram illustrating a line type head used for an image formation unit and a post-treatment liquid discharge unit of the image formation apparatus of FIG. 1 ;

FIG. 4B is a partially enlarged view illustrating a line type head used for an image formation unit of the image formation apparatus of FIG. 1 ;

FIG. 5A is a schematic cross-sectional view illustrating an image formation unit and a post-treatment liquid discharge unit of an image formation apparatus according to an embodiment of the present invention;

FIG. 5B is a schematic cross-sectional view illustrating an image formation unit and a post-treatment liquid discharge unit of an image formation apparatus according to an embodiment of the present invention;

FIG. 6A is a top view illustrating a recording medium when an image formation apparatus according to an embodiment of the present invention has formed an image;

FIG. 6B is cross-sectional view illustrating a recording medium when an image formation apparatus according to an embodiment of the present invention has formed an image;

FIG. 7 is an illustration of an image formation unit and a post-treatment liquid discharge unit according to an embodiment of the present invention;

FIG. 8 is an illustration of a maintenance and recovery operation for an image formation unit and a post-treatment liquid discharge unit according to an embodiment of the present invention;

FIG. 9 is a plan view of an image formation unit, a post-treatment liquid discharge unit, and a maintenance and recovery unit according to an embodiment of the present invention;

FIG. 10A is a schematic configuration diagram illustrating a control unit of an image formation apparatus according to an embodiment of the present invention;

FIG. 10B is a schematic configuration diagram illustrating a control unit of an image formation apparatus according to an embodiment of the present invention;

FIG. 11 is a functional block diagram illustrating functions of a control unit of an image formation apparatus according to an embodiment of the present invention;

FIG. 12 is a functional block diagram illustrating a data management unit of a control unit of an image formation apparatus according to an embodiment of the present invention; FIG. 13 is a functional block diagram illustrating an image output unit of a control unit of an image formation apparatus according to an embodiment of the present invention;

FIG. 14 is a diagram illustrating test patterns for a discharge examination of an image formation unit;

FIG. 15 is a diagram illustrating test patterns for a discharge examination of a post-treatment unit according to Example 1-1 of the present invention;

FIG. 16 is a diagram illustrating driving waveforms of an image formation unit when forming the test patterns for a discharge examination shown in FIG. 15 ;

FIG. 17 is a diagram illustrating driving waveforms of the post-treatment unit when forming the test patterns for a discharge examination shown in FIG. 15 ;

FIG. 18 is a flowchart of steps of a discharge examination of transparent droplets of the post-treatment unit according to Example 1-1 of the present invention;

FIG. 19 is a diagram illustrating test patterns for a discharge examination of a post-treatment unit according to Example 1-2 of the present invention;

FIG. 20 is a diagram illustrating a driving waveform of the post-treatment unit when forming the test patterns for a discharge examination shown in FIG. 19 ;

FIG. 21 is a flowchart of steps of a discharge examination of transparent droplets of the post-treatment unit according to Example 1-2 of the present invention;

FIG. 22 is a diagram illustrating test patterns for a discharge examination of a post-treatment unit according to Example 1-3 of the present invention;

FIG. 23 is a diagram illustrating a driving waveform of the post-treatment unit when forming the test patterns for a discharge examination shown in FIG. 22 ;

FIG. 24A is a diagram illustrating test patterns for a discharge examination of a post-treatment unit according to Example 2 of the present invention;

FIG. 24B is another diagram illustrating test patterns for a discharge examination of the post-treatment unit according to Example 2 of the present invention;

FIG. 24C is another diagram illustrating test patterns for a discharge examination of the post-treatment unit according to Example 2 of the present invention;

FIG. 25A is a diagram illustrating a discharge head of a post-treatment unit according to Example 3 of the present invention;

FIG. 25B is a diagram illustrating the discharge head of the post-treatment unit according to Example 3 of the present invention;

FIG. 26 is a diagram illustrating test patterns for a discharge examination using the discharge head shown in FIGS. 25A and 25B ;

FIG. 27A is a schematic diagram illustrating use of a serial type head for a post-treatment liquid discharge unit of the image formation apparatus of FIG. 1 ;

FIG. 27B is a top view illustrating use of a serial type head for the post-treatment liquid discharge unit of the image formation apparatus of FIG. 1 ; and

FIG. 28 is a diagram illustrating test patterns for a discharge examination of a post-treatment liquid discharge unit using the discharge head shown in FIGS. 27A and 27B .

(Configuration of Image Formation Apparatus)

An image formation apparatus 100 according to an embodiment of the present invention will be described with reference to FIGS. 1-5B . In the present embodiment, the image formation apparatus 100 has a discharge head (recording head, ink head) of four colors: black (K), cyan (C), magenta (M), and yellow (Y). However, image formation apparatuses to which the present invention can be applied are not limited to those image formation apparatuses having such a discharge head. In other words, image formation apparatuses to which the present invention can be applied include those image formation apparatuses further having a discharge head for green (G), red (R), light cyan (LC), and/or another color or having only a discharge head for black (K). In the following description, a reference numeral provided with K, C, M, or Y as a suffix is assumed to correspond to black, cyan, magenta, or yellow, respectively.

Further, although rolled continuous paper is used as a recording medium (hereafter “roll paper Md”) in the present embodiment, recording mediums on which the image formation apparatus 100 according to the present invention can form an image are not limited to the roll paper Md. In other words, recording media on which the image formation apparatus 100 according to the present invention can form an image may include cut paper. Further, recording media on which the image formation apparatus 100 according to the present invention can form an image may include regular paper, high-quality paper, thin paper, cardboard, recording paper, roll paper, OHP sheet, synthetic resin film, metallic thin film, and other materials on which an image can be formed using ink or the like. The roll paper Md here includes continuous paper (continuous sheets, continuous form paper) in which perforations that allow cutting are formed at predetermined intervals. Further, a page in the roll paper Md is assumed to be a region between the perforations formed at predetermined intervals, for example.

As shown in FIG. 1 , the image formation apparatus 100 according to the embodiment of the present invention includes a carrying-in unit 10 that carries in the roll paper Md (recording medium), a pretreatment unit 20 that pretreats the roll paper Md that has been carried in, and a drying unit 30 that dries the roll paper Md that has been pretreated. Further, the image formation apparatus 100 includes an image formation unit 40 that forms an image on a surface of the roll paper Md, a post-treatment unit 50 that performs post-treatment on the roll paper Md on which the image is formed, and a carrying-out unit 60 that carries out the roll paper Md that has been subjected to the post-treatment. The image formation unit 40 , the post-treatment unit 50 , and maintenance and recovery units 90 A and 90 B are disposed on a case 74 of a printer engine 72 E. The case 74 serving as an inkjet printer body includes a carrying unit 80 having a carrying belt 81 or the like. The image formation unit 40 , the post-treatment unit 50 , the maintenance and recovery units 90 A and 90 B, cases 73 and 74 , and a post-treatment drying unit 32 correspond to the printer engine 72 E to be described later. Further, the image formation apparatus 100 includes a control unit 70 (see FIG. 11 ) that controls operations of the image formation apparatus 100 .

In the image formation apparatus 100 according to the present embodiment, the carrying-in unit 10 carries in roll paper Md, the pretreatment unit 20 pretreats a surface of the roll paper Md, and the drying unit 30 dries the surface of the roll paper Md. Further, in the image formation apparatus 100 , the image formation unit 40 forms an image on the surface of the roll paper Md that has been pretreated and dried. Further, in the image formation apparatus 100 , the post-treatment unit 50 performs post-treatment on the roll paper Md on which the image is formed. Then, in the image formation apparatus 100 , the carrying-out unit 60 rolls up (ejects, carries out) the roll paper Md.

In the following, each configuration of the image formation apparatus 100 according to the embodiment of present invention will be specifically described. The image formation apparatus 100 to which the present invention is applied may be configured without including one or more of the pretreatment unit 20 and the like described below depending on a type of the recording medium on which the image is formed.

(Configuration of Carrying-in Unit)

The carrying-in unit 10 carries the recording medium to the pretreatment unit 20 , for example. In the present embodiment, the carrying-in unit 10 is configured with a paper feeding unit 11 and a plurality of carrying rollers 12 . The carrying-in unit 10 uses the carrying rollers 12 to carry in (move) the roll paper Md rolled up and held on a paper feeding roller of the paper feeding unit 11 and carries the roll paper Md to the pretreatment unit 20 using a platen, for example.

(Configuration of Pretreatment Unit)

The pretreatment unit 20 pretreats the recording medium before an image is formed. In the present embodiment, the pretreatment unit 20 pretreats a surface of the roll paper Md with a pretreatment liquid, the roll paper Md been carried in by the carrying-in unit 10 .

The pretreatment here refers to treatment to evenly coat the surface of the roll paper Md (recording medium) with the pretreatment liquid that has a function of coagulating ink. In accordance with this, when the image formation apparatus 100 forms an image on paper exclusively used for inkjet printing or on a recording medium other than such an exclusive paper, the image formation apparatus 100 can coat the surface of the recording medium with the pretreatment liquid that has the function of coagulating ink by using the pretreatment unit 20 before the image is formed on the recording medium.

Accordingly, the image formation apparatus 100 is capable of reducing generation of a quality problem in an image to be formed involving blur, density, color tone, and set-off and reducing generation of a problem related to water resistance, weatherability, and image fastness. Accordingly, it is possible to improve quality of an image to be formed thereafter.

An example of the pretreatment unit 20 that uses a roll coating method is described with reference to FIG. 2 . As shown in FIG. 2 , the pretreatment unit 20 in the present embodiment coats the surface of the roll paper Md with a stored pretreatment liquid 20 L, the roll paper Md being carried in (carried to) the pretreatment unit 20 by the carrying-in unit 10 ( FIG. 1 ).

Specifically, the pretreatment unit 20 first transfers (moves) the pretreatment liquid 20 L to a surface of a coating roller 23 in a film state by using a stirring (providing) roller 21 and a thinning (transport) roller 22 . Next, the pretreatment unit 20 presses the coating roller 23 on a rotating platen roller 24 in order to rotate the coating roller 23 . In this case, the pretreatment unit 20 can coat the surface of the roll paper Md with the pretreatment liquid 20 L by carrying the roll paper Md between the coating roller 23 and the platen roller 24 .

Further, the pretreatment unit 20 uses a pressure regulating device 25 to control a nip pressure (applied to a position where the coating roller 23 and the platen roller 24 are brought into contact) when the pretreatment liquid 20 L is being applied. In addition or alternatively, the pretreatment unit 20 controls a rotational speed of the coating roller 23 and the platen roller 24 . In accordance with this, the pretreatment unit 20 changes the rotational speed of the coating roller 23 and the like. In accordance with these features, the pretreatment unit 20 can control (change) a coating amount (such as film thickness, liquid amount, adhesion amount, or dry adhesion amount) of the pretreatment liquid 20 L by changing the nip pressure using the pressure regulating device 25 . Accordingly, the pretreatment unit 20 can coat the surface of the roll paper Md (recording medium) with the pretreatment liquid 20 L while adjusting the coating amount to be suitable for image formation and post-treatment thereafter.

(Configuration of Drying Unit)

The drying unit 30 dries the recording medium by heating, for example. The drying unit 30 of the present embodiment includes a pretreatment drying unit 31 that dries the roll paper Md pretreated by the pretreatment unit 20 and a post-treatment drying unit 32 that dries the roll paper Md subjected to post-treatment by the post-treatment unit 50 .

The pretreatment drying unit 31 using heating rollers is described below. Heating rollers 311 - 316 are preferably disposed in multiple stages as shown in FIG. 3 in order to improve drying effects. In accordance with this, the pretreatment drying unit 31 uses the heating rollers 311 - 316 to heat the surface of the roll paper Md coated with the pretreatment liquid and vaporize moisture of the pretreatment liquid, thereby drying (the pretreatment liquid of) the roll paper Md. In this configuration, if drying intensity is to be lowered, a temperature of the heating rollers is lowered to be 40-80° C., for example. Further, only the heating rollers 311 and 312 are heated while the other heating rollers 313 - 316 are not heated. By contrast, it is possible to raise the drying intensity by increasing a number of heating rollers to be used or raising the temperature of the heating rollers.

While the drying intensity is controlled here in accordance with the temperature of the heating rollers and the number of the heating rollers to be used, the drying intensity can also be controlled by either of them. As mentioned above, it is possible to control the drying intensity using the temperature of the heating rollers and/or the number of the heating rollers to be used.

In addition, in the pretreatment drying unit 31 , elements used for drying are not limited to heating rollers. In other words, the pretreatment drying unit 31 may employ infrared drying, microwave drying, hot-air drying, or other drying methods. Further, the pretreatment drying unit 31 may use a drying method in which a plurality of drying methods are combined. Further, the pretreatment drying unit 31 may heat the roll paper Md (recording medium) before the pretreatment unit 20 coats the roll paper Md with the pretreatment liquid (preheating step).

A configuration of the post-treatment drying unit 32 is the same as the configuration of the pretreatment drying unit 31 , so that a description thereof is omitted.

(Configuration of Image Formation Unit)

The image formation unit 40 forms an image on a recording medium. The image formation unit 40 in the present embodiment forms an image on a surface of the roll paper Md by discharging droplets (hereafter “ink”) onto the roll paper Md dried by the drying unit 30 .

An example of an outer shape of the image formation unit 40 is described with reference to FIGS. 4A and 4B . FIG. 4A is a schematic plan view showing an entire configuration of the image formation unit 40 of the image formation apparatus 100 according to the embodiment of the present invention. FIG. 4B is a schematic plan view showing a main body (discharge head 40 K for black (K)) of the image formation unit 40 .

As shown in FIG. 4A , in the present embodiment, the image formation unit 40 may use a full-line type head. In other words, in the image formation unit 40 , four discharge heads 40 K, 40 C, 40 M, and 40 Y for black (K), cyan (C), magenta (M), and yellow (Y) are disposed upstream in a carrying direction Xm of the recording medium.

In the present embodiment, the discharge head 40 K for black (K) includes four head units 40 K- 1 , 40 K- 2 , 40 K- 3 , and 40 K- 4 disposed in a staggered manner in a direction orthogonal to the carrying direction Xm of the roll paper Md. In accordance with this, the image formation unit 40 can form an image on an entire area in a width direction (orthogonal to the carrying direction Xm) of an image formation region (printing region) on the roll paper Md (recording medium). Since the recording medium is carried in the carrying direction Xm by the carrying belt 81 , the discharge head 40 K is moved relative to the recording medium (in a direction opposite to the carrying direction Xm of the recording medium). In addition, a configuration of the other discharge heads 40 C, 40 M, and 40 Y is the same as the configuration of the discharge head 40 K for black (K), so that a description thereof is omitted.

FIG. 4B is an enlarged view of the head unit 40 K- 1 of the discharge head 40 K for black (K) of the image formation unit 40 . As shown in FIG. 4B , the head unit 40 K- 1 in the present embodiment includes a plurality of discharge ports (nozzles, printing nozzles) 40 N on a nozzle surface (outer surface of a nozzle plate 43 shown in FIG. 5A described below). The plurality of discharge ports 40 N are arranged in line in a longitudinal direction of the head unit 40 K- 1 and constitute a nozzle line. The head unit 40 K- 1 may include a plurality of nozzle lines. While the discharge heads shown in FIG. 4A have two nozzle lines and two adjacent head units discharge droplets for one line, the head may have another shape. For example, a plurality of head units may be connected and arranged in line to constitute the head. Further, one head unit that has one nozzle line extending in the width direction of the recording medium for one line may constitute one head.

These discharge heads 40 K, 40 C, 40 M, and 40 Y installed on a carriage 46 (see FIG. 7 ) serve as a first discharge unit that discharges ink (color droplets).

A cross-sectional shape of the discharge head of the image formation unit 40 is described with reference to FIGS. 5A and 5B . FIG. 5A is a schematic cross-sectional view illustrating a flow channel (cross section in a longitudinal direction of a liquid chamber 40 F) of the image formation unit 40 . FIG. 5B is a cross-sectional view illustrating arrangement of the discharge ports 40 N of the image formation unit 40 (cross section (taken along line SC 1 -SC 1 in FIG. 5A ) in a lateral direction of the liquid chambers 40 F (direction where the discharge ports are arranged)).

As shown in FIG. 5A , the discharge head ( 40 K, for example) of the image formation unit 40 according to the embodiment of the present invention includes a flow channel plate 41 that forms a passage of ink to be discharged, a vibration plate 42 joined to an undersurface (inner direction of the discharge head) of the flow channel plate 41 , the nozzle plate 43 joined to an upper surface (outer direction of the discharge head) of the flow channel plate 41 , and a frame member 44 that holds a peripheral part of the vibration plate 42 . Further, the discharge head also includes a pressure generation unit (actuator unit) 45 that deforms the vibration plate 42 .

Since the flow channel plate 41 , the vibration plate 42 , and the nozzle plate 43 are piled up, the discharge head ( 40 K, for example) according to the present embodiment can form the liquid chamber 40 F and a nozzle communication channel 40 R that is in communication with the discharge port (nozzle) 40 N. Further, since the frame member 44 is further piled up, the discharge head can form an ink inflow port 40 S to supply the liquid chamber 40 F with ink and a common liquid chamber 40 D to supply the liquid chamber 40 F with ink.

Further, the discharge head can deform (deflective deformation) the vibration plate 42 by using the pressure generation unit 45 . In accordance with this, the discharge head can change capacity (volume) of the liquid chamber 40 F and change pressure applied to ink within the liquid chamber 40 F. As a result of this, the discharge head can discharge the ink from the discharge ports 40 N.

In the present embodiment, in the frame member 44 , a housing portion where the pressure generation unit 45 is housed, a concave part that serves as the common liquid chamber 40 D, and an ink supply port 401 N to supply the common liquid chamber 40 D with ink from the outside of the discharge head are formed.

The pressure generation unit 45 may employ an electromechanical conversion element. The pressure generation unit 45 in the present embodiment includes a piezoelectric element 45 P that serves as the electromechanical conversion element, a base substrate 45 B that joins and fixes the piezoelectric element 45 P, and a support disposed in a space between adjacent piezoelectric elements 45 P. Further, the pressure generation unit 45 includes an FPC cable 45 C, for example, to connect the piezoelectric element 45 P to a driving circuit (driving IC) (not shown).

The piezoelectric element 45 P may employ a laminated piezoelectric element (PZT) as shown in FIG. 5B in which a piezoelectric material 45 Pp and an internal electrode 45 Pe are alternately laminated. The internal electrode 45 Pe includes a plurality of individual electrodes 45 Pei and a plurality of common electrodes 45 Pec. In the present embodiment, the individual electrode 45 Pei and the common electrode 45 Pec are alternatively connected to an end surface of the piezoelectric material 45 Pp. Further, the piezoelectric element 45 P uses d33 direction as a piezoelectric direction of the piezoelectric element 45 P. In accordance with this, the pressure generation unit 45 can pressurize or depressurize ink within the liquid chamber 40 F by using piezoelectric effects (displacement in the d33 direction) of the piezoelectric element 45 P. The pressure generation unit 45 may pressurize or depressurize the ink within the liquid chamber 40 F by using displacement in d31 direction of the piezoelectric element 45 P. Further, in the pressure generation unit 45 , a line of piezoelectric elements may be disposed for one discharge port 40 N. In addition, the support may be formed together with the piezoelectric element 45 P when a piezoelectric element member (piezoelectric element 45 P) is divided. In other words, the discharge head can use the piezoelectric element member as the support by not applying voltage to the piezoelectric element 45 P.

The pressure generation unit 45 used in the present embodiment is not limited to the above-mentioned example (piezoelectric element 45 P). In other words, the pressure generation unit 45 may employ a method (what is called a thermal type) for generating bubbles by heating the ink within the liquid chamber 40 F using a heating element (see Japanese Laid-Open Patent Application No. 61-59911, for example). Further, the pressure generation unit 45 may employ a method (what is called an electrostatic type) by which a vibration plate and an electrode are disposed on wall surfaces of the liquid chamber 40 F to face each other, and the vibration plate is deformed by electrostatic force generated between the vibration plate and the electrode (see Japanese Laid-Open Patent Application No. 6-71882, for example).

(Configuration of Post-Treatment Unit)

The post-treatment unit 50 performs post-treatment on the recording medium on which an image has been formed. The post-treatment unit 50 uses a post-treatment liquid to perform the post-treatment on a surface of the roll paper Md on which the image has been formed by the image formation unit 40 .

The post-treatment refers to treatment to discharge (deposit) a post-treatment liquid 50 L (described later) onto the roll paper Md (recording medium). The post-treatment liquid 50 L is applied in spots or in stripes, for example. In accordance with this, it is possible to improve abrasion resistance, glossiness, and preservation stability (such as water resistance, light resistance, and gas resistance) of the recording medium on which the image is formed. As shown in FIGS. 6A and 6B , for example, when the post-treatment by the post-treatment unit 50 starts, the surface of the roll paper Md has already been coated with the pretreatment liquid 20 L and ink 40 Ink that forms the image has been further discharged thereon. The post-treatment unit 50 of the image formation apparatus 100 according to the embodiment of the present invention performs the post-treatment to discharge (deposit) the post-treatment liquid 50 L onto the roll paper Md on which the image has been formed.

FIG. 6B is a schematic diagram illustrating a predetermined cross section of the recording medium. The post-treatment liquid 50 L is discharged (deposited) in an area smaller than at least an area of the pretreatment liquid 20 L. Further, in this cross section, the ink 40 Ink is discharged onto an entire area and the post-treatment liquid 50 L is discharged (deposited) in the area smaller than an area of the ink 40 Ink.

While the post-treatment liquid 50 L seems to be formed in spots in FIG. 6B , the post-treatment liquid 50 L may be formed in stripes in a direction orthogonal to the cross section.

The post-treatment liquid 50 L may be discharged (deposited) in a portion where the image is formed on the recording medium, in an area smaller than a surface area where the image is formed. The post-treatment liquid 50 L may or may not be discharged in a portion where the image is not formed.

As a post-treatment method, the post-treatment liquid 50 L is preferably deposited (discharged) onto only a specified portion in a field of the roll paper Md where the image is formed. Further preferably, the post-treatment unit 50 changes a discharging amount (coating amount) and a discharging (coating) method of the post-treatment liquid 50 L based on a type, permeability, glossiness, and/or resolution of the recording medium, and/or a coating amount (liquid amount) of the pretreatment liquid 20 L coated by the pretreatment unit 20 .

Further, the post-treatment unit 50 according to the present embodiment can discharge the post-treatment liquid 50 L in any region (any location) with a desired discharging amount (in desired spots or desired stripes) using the same discharge head as in the image formation unit 40 shown in FIGS. 4A and 4B .

Specifically, the post-treatment unit 50 can select (1) discharging in an entire field of an area of the roll paper Md where an image can be formed; (2) discharging in a field where the image is formed; (3) discharging only in a field of an image formation portion (where dots are discharged); or (4) discharging in a field larger than the image formation portion of the roll paper Md (recording medium), the field being larger than an outer edge of the image formation portion by 1 or more dots, for example. Further, the post-treatment unit 50 can discharge the post-treatment liquid 50 L in an no field (in spots or in stripes) relative to a selected field where the post-treatment liquid 50 L is to be discharged. In this case, no may be set to 5-50%. Further, n % may be predetermined through experiments, numerical calculation, or the like.

Further, the post-treatment unit 50 according to the present embodiment can select, as a method for discharging the post-treatment liquid 50 L, (1) discharging based on a printing duty or (2) discharging based on a droplet amount of the post-treatment liquid 50 L to be discharged, for example. In this case, the post-treatment unit 50 may calculate the printing duty and the droplet amount of the post-treatment liquid 50 L from input information (print image data, for example) and determine the method for discharging based on a calculated printing duty or the like.

Thus, according to the image formation apparatus 100 in the embodiment of the present invention, it is possible to use the post-treatment unit 50 to deposit (discharge) the post-treatment liquid 50 L only in a specified portion in a field where an image is formed in comparison with a case where the post-treatment liquid 50 L is coated (discharged) onto an entire area of the recording medium. Thus, according to the image formation apparatus 100 in the present embodiment, it is possible to reduce time required for post-treatment or time required for drying the post-treatment liquid 50 L in particular. Further, it is possible to reduce a liquid amount of the post-treatment liquid 50 L required for post-treatment. Thus, it is possible to reduce cost required for the post-treatment.

In addition, the post-treatment method performed by the post-treatment unit 50 is not especially limited, so that another post-treatment method may be selected where necessary depending on a type of the post-treatment liquid 50 L. The post-treatment method performed by the post-treatment unit 50 preferably employs the same method as used for discharging ink of the image formation unit 40 in terms of size reduction of an apparatus and preservation stability of the post-treatment liquid 50 L. Accordingly, a configuration of the post-treatment unit 50 is determined in the same manner with reference to FIG. 4A . A post-treatment liquid discharge unit includes a plurality of discharge ports (nozzles, printing nozzles) 50 N on a nozzle surface (outer surface of a nozzle plate 53 shown in FIG. 5A ). A head 50 that serves as the post-treatment liquid discharge unit including the nozzle plate 53 is installed on a carriage 56 (see FIG. 7 ) and the head 50 serves as a second discharge unit that discharges the post-treatment liquid 50 L (transparent droplets).

When the post-treatment liquid 50 L is to be discharged, a suitable amount of a water-soluble organic solvent (wetting agent) used in a method for discharging ink of the image formation unit 40 is preferably contained. Further, in the post-treatment unit 50 according to the present embodiment, a dry adhesion amount of the post-treatment liquid 50 L is preferably 0.5 g/m 2 to 10 g/m 2 .

The post-treatment unit 50 according to the present embodiment may use, as the post-treatment liquid 50 L, a treatment liquid that contains a component that can form a transparent protective layer on the roll paper Md (recording medium). Examples of such a treatment liquid that contains a component that can form a transparent protective layer include a treatment liquid that contains water-dispersible resin (resin), water-soluble organic solvent (wetting agent), penetrant, surface-active agent, water, and/or other components where necessary. Further, the post-treatment liquid 50 L may be a resin composition that contains a component that polymerizes under ultraviolet irradiation and/or thermoplastic resin. Further, the post-treatment liquid 50 L preferably includes a thermoplastic resin emulsion in order to improve glossiness and a fixing property. In accordance with this, the post-treatment unit 50 can increase the glossiness of a surface of the roll paper Md on which an image is formed or protect the surface of the roll paper Md with a resin layer depending on a discharging (coating) method.

By using such a post-treatment apparatus, it is possible to prevent detachment (removal) of an image (ink) on the recording medium when the surface of the roll paper Md on which the image is formed rubs against another object (another recording medium, for example). In other words, it is possible to improve abrasion resistance (friction resistance). Further, it is possible to reduce generation of a quality problem in an image to be formed involving blur, density, color tone, glossiness, and set-off and to reduce generation of a problem related to water resistance, weatherability, and image fastness.

(Maintenance and Recovery Unit)

The maintenance and recovery units 90 A and 90 B maintain and recover (restore performance of) the image formation unit 40 and the post-treatment unit 50 . When the image formation unit 40 and the post-treatment unit 50 that employ the above-mentioned head (see FIG. 4A ) are used for a long period of time, the head may be clogged with the ink or the post-treatment liquid. Accordingly, it is desirable to perform a maintenance and recovery operation (cleaning and maintenance) when not performing printing such as before printing. FIGS. 7-9 show the maintenance and recovery units 90 A and 90 B in which a line type head is used for the image formation unit 40 and the post-treatment unit 50 .

FIG. 7 is a schematic diagram illustrating a discharge head, a post-treatment liquid output unit, and a maintenance and recovery unit in the embodiment of the present invention. In FIG. 7 , the image formation unit (ink head) 40 and the post-treatment unit (post-treatment liquid output unit, head) 50 are disposed so as to face the carrying belt 81 serving as a carrying unit. The carrying belt 81 carries the recording medium in the carrying direction Xm shown by an arrow. The maintenance and recovery unit 90 A (maintenance unit) is disposed upstream (right side in FIG. 7 ) relative to the image formation unit 40 and the maintenance and recovery unit 90 B (maintenance unit) is disposed downstream (left side in FIG. 7 ) relative to the post-treatment unit 50 in the carrying direction Xm of the recording medium. The maintenance and recovery units 90 A and 90 B maintain and recover the image formation unit 40 and the post-treatment unit 50 each including a line type head.

The heads of the image formation unit 40 and the post-treatment unit 50 are configured to be vertically movable. The discharge heads 40 K, 40 C, 40 M and 40 Y (first discharge unit) for four colors serving as the image formation unit are disposed on the carriage 46 and the head 50 (second discharge unit) that discharges the post-treatment liquid 50 L is disposed on the carriage 56 .

The carriages 46 and 56 can move between a position close to the carrying unit 80 shown in FIG. 7 , namely, a recording position which is a printing position to discharge a liquid (ink, post-treatment liquid) and a spaced position which is a position spaced apart from the carrying unit 80 as shown in FIG. 8 . This spaced position functions as a maintenance position to maintain the image formation unit 40 and the post-treatment unit 50 by the maintenance and recovery units 90 A and 90 B. The spaced position also functions as a standby position to wait for a next operation and as a recovery position to perform maintenance.

In order to perform this vertical movement, the carriages 46 and 56 are respectively supported by carriage position movement units 47 and 57 . When the carriage position movement units 47 and 57 are operated, positions of the carriages 46 and 56 are vertically moved relative to the case 74 of the printer engine 72 E having the carrying belt 81 . In addition, while the carriage position movement units 47 and 57 are indicated by arrows in FIG. 7 , a movement mechanism including a rail and a roller used in combination may be employed for the carriage position movement units 47 and 57 or an arm or the like may be used to lift the carriage position movement units 47 and 57 .

In the carrying unit 80 , the carrying belt 81 is stretched and installed for rotational movement between a driving roller 83 rotated by a motor and a driven roller 82 . The recording medium is carried in accordance with the rotational movement of the carrying belt 81 supported by a supporting member 84 . The supporting member 84 may include a suction unit or an electrostatic attraction unit in order to attract paper while carrying the paper.

Further, the maintenance and recovery unit 90 A includes an engagement unit 91 A and a cleaning unit 95 A. The maintenance and recovery unit 90 B includes an engagement unit 91 B and a cleaning unit 95 B.

When maintenance is performed, the engagement unit 91 A is reciprocated to an opposite field that faces the discharge heads 40 K, 40 C, 40 M and 40 Y serving as the image formation unit 40 in the spaced position (dotted line in FIG. 7 ) and the engagement unit 91 A is selectively engaged with the discharge heads 40 K, 40 C, 40 M and 40 Y. When maintenance is performed, the engagement unit 91 B is reciprocated to an opposite field that faces the head 50 serving as the post-treatment unit 50 in the spaced position (dotted line in FIG. 7 ) and the engagement unit 91 B is engaged with the head 50 .

Since the maintenance and recovery units 90 A and 90 B have the same configuration except a number of cap units and liquid to be received (ink, post-treatment liquid), the same configuration is described with reference to the maintenance and recovery unit 90 B of the post-treatment unit 50 to be controlled in the present embodiment and a description of the same configuration of the maintenance and recovery unit 90 A is omitted. Further, for elements used in common in the maintenance and recovery units 90 A and 90 B, reference numerals added to ends thereof are omitted.

The engagement unit 91 includes a cap unit 92 , a wiper 93 , and a fixing member 94 that fixes the cap unit 92 and the wiper 93 . The cap unit 92 engages the head 50 in the spaced position in order to seal and cap the nozzles 50 N of the head 50 . When the maintenance is performed, the head 50 performs what is called an idle discharge to discharge the post-treatment liquid 50 L while the cap unit 92 is engaged. The cap unit 92 functions as an idle discharge receiver that receives the post-treatment liquid 50 L discharged from the head 50 by the idle discharge. The wiper 93 performs cleaning (wiping) on the head 50 by wiping off the post-treatment liquid 50 L flowing from the head 50 in the spaced position.

A cleaning unit 95 performs cleaning on the cap unit 92 , the wiper 93 , and the like while the engagement unit 91 is in a home position thereof after the engagement unit 91 is reciprocated when the maintenance is performed. In addition, the cleaning of the engagement unit 91 by the cleaning unit 95 may be regularly performed after a predetermined number of images are formed, for example.

The maintenance and recovery unit 90 also includes a pump 96 serving as a suction unit that suctions the post-treatment liquid 50 L inside the head 50 and drains the post-treatment liquid 50 L to the outside of the head 50 while the cap unit 92 is engaged with the head 50 in the spaced position. The maintenance and recovery unit 90 further includes a drain passage that connects the cap unit 92 to the pump 96 and drains the post-treatment liquid 50 L to the outside of the head 50 and a fluid collection unit connected to the drain passage, the fluid collection unit collecting liquids (ink, post-treatment liquid) draining to the outside of the head 50 .

FIG. 9 is a plan view of FIG. 7 . As shown in FIG. 9 , the maintenance and recovery unit 90 A includes cap units 92 K, 92 C, 92 M, and 92 Y for each head segment serving as the image formation unit 40 in a direction orthogonal to the carrying direction Xm of the recording medium, and the maintenance and recovery unit 90 B includes a cap unit 92 B.

Further, the maintenance and recovery unit 90 includes a movement unit that moves the engagement unit 91 . As the movement unit of the engagement unit 91 , the maintenance and recovery unit 90 includes a reciprocation unit ( 97 , 98 , 99 ) that reciprocates the engagement unit 91 to the heads 40 , 50 and a vertical movement unit ( 75 ) that supports the reciprocation unit and moves the cap unit 92 vertically, the vertical movement unit ( 75 ) being integrated with the engagement unit 91 .

The reciprocation unit includes the fixing member 94 integrated with the engagement unit 91 , an endless belt 97 whose portion fixes the fixing member 94 , and two pulleys 98 on which the endless belt 97 is wound. The reciprocation unit further includes a position sensor 99 ( 99 K, 99 C, 99 M, 99 Y, and 99 B) that detects being positioned directly below the head 40 or 50 and being positioned in the home position (where reciprocation starts). The reciprocation unit further includes a support table that supports the engagement unit 91 from below reciprocatively as mentioned above and a motor or the like that rotates the pulley 98 as a driving unit.

Further, the vertical movement unit 75 includes base members 75 A and 75 B on which the support table including the endless belt 97 is placed, the base members 75 A and 75 B being arranged and fixed below from above the case 74 across a paper movement space. A bottom face of these base members 75 A and 75 B is screwed with a shaft serving as a driving shaft and connected to a plurality of gears fixed on the other end of the shaft, the plurality of gears being rotated together with the shaft. The plurality of gears are connected to a stepping motor that rotates the gears.

Accordingly, it is possible to reciprocate the engagement unit 91 by driving the motor to rotate the pulley 98 for rotation movement of the endless belt 97 as the reciprocation unit. In this case, by driving the motor such that any one of the position sensors 99 detects the fixing member 94 , it is possible to position the cap units 92 K, 92 C, 92 M, and 92 Y or the cap unit 92 B to face the discharge heads 40 K, 40 C, 40 M, and 40 Y or the head 50 in the spaced position or to position the cap units 92 K, 92 C, 92 M, and 92 Y or the cap unit 92 B in the home position with precision.

Further, while the cap units 92 K, 92 C, 92 M, 92 Y, and 92 B are positioned to face the discharge heads 40 K, 40 C, 40 M, 40 Y, and the head 50 by the position sensor 99 , by driving the stepping motor a predetermined amount, namely, a predetermined number of pulses, the base members 75 A and 75 B are moved upward. In accordance with this, it is possible to move the engagement units 91 A and 91 B upward by a predetermined amount and engage them with the discharge heads 40 K, 40 C, 40 M and 40 Y or the head 50 in the spaced position the cap units 92 K, 92 C, 92 M, 92 Y, and 92 B face. In addition, instead of using the stepping motor, a sensor that detects a position of the cap unit 92 in the vertical direction may be used in combination with a motor.

When such a configuration is used to perform a maintenance and recovery operation, as shown in FIG. 8 , the image formation unit 40 and the post-treatment unit 50 are moved upward to be in the spaced position while the engagement units 91 A and 91 B of the maintenance and recovery units 90 A and 90 B are stopped directly below each head in the spaced position and are engaged.

In the embodiment of the present invention, before the maintenance and recovery operation is performed, test patterns to be described below are formed and a user, an administrator, or a service person confirms the test patterns printed on the recording medium by visual observation. Further, a maintenance and recovery operation described below is performed only if maintenance (cleaning, for example) is determined to be necessary by visual observation. Further, maintenance is performed only on a head segment that requires such maintenance depending on a result of the visual observation of the test patterns.

Specifically, depending on the result of the visual observation of the test patterns, the maintenance and recovery operation is performed only on the cap unit 92 K, 92 C, 92 M, 92 Y, or 92 B that requires maintenance. Further, in each cap unit such as the cap unit 92 B for post-treatment, the maintenance and recovery operation can be performed only on a portion for a specific nozzle ( 50 N) within a corresponding head segment.

In the maintenance and recovery operation, the nozzles 40 N and 50 N of the heads in the image formation unit 40 and the post-treatment unit 50 are capped with the cap unit 92 for idle charge reception. Ink and post-treatment liquid within the heads are suctioned by the pump 96 from the discharge ports 40 N and the nozzles 50 N via the cap unit 92 .

When nozzle suction is complete as the maintenance and recovery operation, after the engagement units 91 A and 91 B are returned to the home position, the image formation unit 40 and the post-treatment unit 50 move downward to a printing position on the carrying unit 80 and assume a printable state.

In the embodiment described with reference to FIGS. 7-9 , the discharge heads 40 K, 40 C, 40 M and 40 Y serving as the image formation unit and the head 50 serving as the post-treatment unit are installed on the carriages 46 and 56 that are independent of each other. In accordance with this, it is possible to maintain the image formation unit and the post-treatment unit at different times.

However, the image formation unit 40 and the post-treatment unit 50 may be integrally configured and installed on the same carriage. In such a configuration, the maintenance and recovery units 90 A and 90 B are also integrally configured, so that the movement mechanism is simplified and the cap units 92 K, 92 C, 92 M, 92 Y, and 92 B are also simplified. In this case, the integrally configured engagement unit 91 collectively caps the discharge heads 40 K, 40 C, 40 M and 40 Y and the head 50 and performs a maintenance and recovery operation. Accordingly, it is possible to collectively dispose the maintenance and recovery units upstream or downstream relative to the image formation unit 40 or the post-treatment unit 50 in the carrying direction Xm of the roll paper Md.

(Configuration of Carrying-Out Unit)

The carrying-out unit 60 carries out (ejects) a recording medium on which an image or the like is formed. As shown in FIG. 1 , the carrying-out unit 60 in the present embodiment is configured with a storage unit 61 and a plurality of carrying rollers 62 . The carrying-out unit 60 uses the carrying rollers 62 to roll up and store the roll paper Md having the image thereon on a storage roller of the storage unit 61 .

If pressure applied to the roll paper Md is great when the roll paper Md is rolled on the storage roller of the storage unit 61 , a drying device that further dries the roll paper Md immediately before the roll paper Md is rolled up may be disposed in order to prevent transfer of another image to a rear surface of the roll paper Md.

(Configuration of Control Unit)

The control unit 70 controls operations of the image formation apparatus 100 . The control unit 70 in the present embodiment sends an instruction to each element of the image formation apparatus 100 to perform an operation and controls the operation. The control unit 70 according to the present embodiment is described with reference to FIGS. 10A-13 .

In addition, the image formation apparatus 100 according to the embodiment of the present invention may employ production printing as a printing system. The production printing here refers to a production system capable of printing (image formation, character printing) on a huge amount of printed matter (image forming medium, character printed matter) in a short time by efficiently performing job management and print data management, for example. Specifically, the image formation apparatus 100 according to the present embodiment performs, with different devices (units), a Raster Image Processor (RIP) process to control an operation to print bitmap data or the like and a print process based on the bitmap data controlled by the RIP process.

Further, the image formation apparatus 100 (control unit 70 ) according to the present embodiment has a workflow system that manages from creation of print data to distribution of printed matter. In other words, the image formation apparatus 100 (control unit 70 ) according to the present embodiment is capable of accelerating printing by separating a device that performs the RIP process that requires processing time from a device that performs the print process.

As shown in FIG. 10A , the control unit 70 of the image formation apparatus 100 according to the embodiment of the present invention includes a higher-level device (DFE: Digital Front End) 71 that performs the RIP process and a printer device 72 that performs the print process. The higher-level device 71 and the printer device 72 here are connected to each other via a plurality of data lines 70 LD and a control line 70 LC.

In the following, the higher-level device 71 and the printer device 72 according to the present embodiment are described in detail.

(Higher-Level Device)

The higher-level device 71 of the control unit 70 in the image formation apparatus 100 according to the embodiment of the present invention performs the RIP process based on print job data (job data, print data) output from a host device. In other words, the higher-level device 71 according to the present embodiment creates sets of bitmap data (hereafter “print image data”) one set being created for each color based on the print job data. The print image data in the present embodiment further includes data about discharge of a post-treatment liquid to be discharged by the post-treatment unit 50 (hereafter “image data about post-treatment”).

Further, the higher-level device 71 according to the present embodiment creates data to control a print operation (hereafter “control information data”) based on the print job data and information about the host device. The control information data here includes data about print conditions (print form, print type, paper feed or ejection information, order of printing surfaces, size of printing paper, data size of print image data, resolution, paper type information, tones, color information, and a number of pages to be printed). Further, the control information data in the present embodiment further includes data about discharge of a post-treatment liquid to be discharged by the post-treatment unit 50 (hereafter “control data about post-treatment”).

Further, when maintenance and recovery is performed, a user, an administrator, or a serviceman inputs information detected by visual observation to the higher-level device 71 .

As shown in 10 B, the higher-level device 71 in the present embodiment includes a Central Processing Unit (CPU) 71 a , a Read Only Memory (ROM) 71 b , Random Access Memory (RAM) 71 c , and a Hard Disk Drive (HDD) 71 d . Further, the higher-level device 71 includes an external I/F 71 e , a control information I/F 71 f , and an image data I/F 71 g . Further, the higher-level device 71 includes a bus 71 h that connects the CPU 71 a and the like. In other words, in the higher-level device 71 , the CPU 71 a and the like are connected to one another to be able to perform transmission and reception mutually via the bus 71 h.

The CPU 71 a controls an entire operation of the higher-level device 71 . The CPU 71 a uses a control program stored in the ROM 71 b and/or the HDD 71 d to control the operation of the higher-level device 71 .

The ROM 71 b , the RAM 71 c , and the HDD 71 d store data and the like, the ROM 71 b and/or the HDD 71 d store the control program to control the CPU 71 a in advance, and the RAM 71 c is used as a work memory for the CPU 71 a.

The external I/F 71 e controls communication (transmission and reception) with an external device (such as the host device) placed outside the image formation apparatus 100 . The control information I/F 71 f controls communication of control information data. The image data I/F 71 g controls communication of print image data. The image data I/F 71 g in the present embodiment has a plurality of channels (described below) for each color of the print image data.

The higher-level device 71 of the control unit 70 according to the present embodiment receives print job data at the external I/F 71 e , the print job data being transmitted from the host device, and uses the CPU 71 a to store the print job data in the HDD 71 d . The higher-level device 71 further uses the CPU 71 a to read out the print job data from the HDD 71 d . Further, the higher-level device 71 uses the CPU 71 a to create bitmap data about each color (yellow (Y), cyan (C), magenta (M), and black (K)) based on the print job data that is read out, and stores created bitmap data about each color in the RAM 71 c . In this case, the higher-level device 71 (CPU 71 a ) can create bitmap data about each color by rendering with Page Description Language (PDL), for example, as an RIP process and write the bitmap data onto the RAM 71 c.

Next, the higher-level device 71 compresses and encodes the bitmap data about each color written onto the RAM 71 c and temporarily stores encoded bitmap data in the HDD 71 d.

Then, when a print operation starts at the printer device 72 , the higher-level device 71 (CPU 71 a ) reads out the encoded bitmap data about each color from the HDD 71 d , decodes the encoded bitmap data, and writes each set of bitmap data about the corresponding color in the RAM 71 c . Then, the higher-level device 71 reads out the bitmap data about each color from the RAM 71 c and outputs the bitmap data as print image data about each color to the printer device 72 (printer engine 72 E described below) via each channel of the image data I/F 71 g . In this case, the higher-level device 71 can output the print image data to the printer device 72 via the data lines 70 LD ( 70 LD-Y, 70 LD-C, 70 LD-M, and 70 LD-K) as the channels of the image data I/F 71 g shown in FIG. 11 .

Further, in accordance with progress of the print operation, the higher-level device 71 according to the present embodiment uses the CPU 71 a to transmit or receive control information data to or from a printer controller 72 C of the printer device 72 via the control information I/F 71 f (control line 70 LC).

Further, when a post-treatment starts at the post-treatment unit 50 , the higher-level device 71 according to the present embodiment uses the CPU 71 a to read out encoded image data about the post-treatment from the HDD 71 d and outputs the image data to the printer engine 72 E via a data line 70 LD-P ( FIG. 11 ) in the same manner as the above-mentioned bitmap data.

(Printer Device)

The printer device 72 of the control unit 70 in the image formation apparatus 100 according to the embodiment of the present invention controls an operation to form an image on a recording medium based on the print image data and the control information data input from the higher-level device 71 . The printer device 72 in the present embodiment includes the printer controller 72 C and the printer engine 72 E. As shown in FIGS. 1 and 11 , the printer engine 72 E includes the case (for carrying) 73 , the case (inkjet printer body) 74 , the image formation unit (head) 40 , the post-treatment unit (head) 50 , the maintenance and recovery units 90 A and 90 B, and the post-treatment drying unit 32 .

The printer controller 72 C controls an operation of the printer engine 72 E described below. The printer controller 72 C transmits or receives the control information data to or from the higher-level device 71 via the control line 70 LC. Further, the printer controller 72 C transmits or receives the control information data to or from the printer engine 72 E via a control line 72 LC. In accordance with this, the printer controller 72 C can store print conditions by writing print information such as various types of print conditions included in the control information data and data about a test pattern for discharge in a register of a print control unit 72 Cc. Further, the printer controller 72 C can control the printer engine 72 E based on the control information data and perform printing in accordance with the print job data (control information data).

As shown in FIG. 11 , the printer controller 72 C in the present embodiment includes a CPU 72 Cp and the print control unit 72 Cc. Further, in the printer controller 72 C, the CPU 72 Cp and the print control unit 72 Cc are connected to each other to be able to perform transmission and reception mutually via a bus 72 Cb. The bus 72 Cb here is connected to the control line 70 LC via a communication I/F.

The CPU 72 Cp uses the control program stored in a ROM to control an entire operation of the printer device 72 . The print control unit 72 Cc transmits or receives a command and status information to or from the printer engine 72 E based on the control information data transmitted from the higher-level device 71 . In accordance with this, the print control unit 72 Cc can control an operation of the printer engine 72 E.

The printer engine 72 E controls an operation to form an image on a recording medium based on the print image data input from the higher-level device 71 and the control information data input from the printer controller 72 C. Further, the printer engine 72 E controls an operation for post-treatment based on the print image data (image data about post-treatment) input from the higher-level device 71 and the control information data (control data about post-treatment) input from the printer controller 72 C.

As shown in FIG. 11 , a plurality of data lines 70 LD ( 70 LD-Y, 70 LD-C, 70 LD-M, 70 LD-K, and 70 LD-P) are connected to the printer engine 72 E. The printer engine 72 E receives the print image data from the higher-level device 71 via the plurality of data lines 70 LD. In accordance with this, the printer engine 72 E can perform a print operation of each color and a post-treatment using a post-treatment liquid based on the received print image data.

The printer engine 72 E in the present embodiment includes a plurality of data management units 72 EC, 72 EM, 72 EY, 72 EK, and 72 EP. Further, the printer engine 72 E includes an image output unit 72 Ei to which a print image, for example, is input from the data management unit 72 EC and a carrying control unit 72 Ecc that controls carrying of a recording medium. Further, the printer engine 72 E in the present embodiment includes a post-treatment liquid output unit 72 Epp to which image data about post-treatment is input from the data management unit 72 EP and a drying control unit after post-treatment 72 Epb that controls an operation of the drying unit 30 ( FIG. 1 ). Further, the printer engine 72 E in the present embodiment further includes a maintenance and recovery control unit 72 Er that controls an operation of a maintenance and recovery mechanism (maintenance and recovery units 90 A and 90 B and carriage position movement units 47 and 57 shown in FIG. 7 ).

Further, in the present embodiment, test patterns used for a maintenance and recovery operation to be described below other than normal printing are included as image data. In addition, the printer engine 72 E may further include a pretreatment liquid coating control unit, a drying control unit after pretreatment, and a drying control unit before rolling up.

A configuration of the data management unit 72 EC is described with reference to FIG. 12 . In addition, a configuration of other data management units 72 EM, 72 EY, 72 EK, and 72 EP is the same as the configuration of the data management unit 72 EC, so that a description thereof is omitted. The data management units 72 EC, 72 EM, 72 EY, and 72 EK used for image formation function as a first driving waveform creation unit. The data management unit 72 EP related to discharge of a post-treatment liquid functions as a second driving waveform creation unit.

As shown in FIG. 12 , the data management unit 72 EC includes a logic circuit 72 EC 1 and a memory unit 72 ECm. The data management unit 72 EC (logic circuit 72 EC 1 ) is connected to the higher-level device 71 via the data line 70 LD-C. The data management unit 72 EC (logic circuit 72 EC 1 ) is also connected to the printer controller 72 C (print control unit 72 Cc) via the control line 72 LC.

In the present embodiment, the memory unit 72 ECm stores print image data output from the higher-level device 71 based on a control signal output from the printer controller 72 C (print control unit 72 Cc).

Further, the logic circuit 72 EC 1 reads out print image data (driving waveform) Ic ( FIG. 12 ) corresponding to cyan (C) from the memory unit 72 ECm based on the control signal output from the printer controller 72 C (print control unit 72 Cc) and outputs the print image data Ic to the image output unit 72 Ei.

Specifically, the logic circuit 72 EC 1 of the data management unit 72 EC creates the driving waveform by creating driving waveform data based on image data received from the higher-level device 71 and the print control unit 72 Cc, performing digital-to-analog conversion on the created driving waveform data, and performing voltage amplification and current amplification.

As for post-treatment, in a case of a logic circuit 72 ECp (data management unit 72 EP), post-treatment liquid discharge data Ip ( FIG. 11 ) about post-treatment and data to control a discharge position of a test pattern for a discharge examination are output to the post-treatment liquid output unit 72 Epp.

The logic circuit 72 ECp of the data management unit 72 EP creates a driving waveform by creating driving waveform data based on a post-treatment liquid test pattern received from the higher-level device 71 and control information about the test pattern received from the print control unit 72 Cc, performing digital-to-analog conversion on the created driving waveform data, and performing voltage amplification and current amplification.

The memory unit 72 ECm here may have a capacity that can store print image data for at least three pages. The print image data for three pages includes print image data about a page being forwarded (received) from the higher-level device 71 , print image data about a page being output to the image output unit 72 Ei, and print image data about a next page, for example.

In addition, the data management unit 72 EC may employ a hardware logic circuit configured with a combination of logic circuits, for example. In accordance with this, the data management unit 72 EC can realize faster processing. Further, the data management unit 72 EC may use the logic circuit 72 EC 1 to perform a logical decision on a control signal based on a bit string, for example, and determine a process to be performed.

A configuration of the image output unit 72 Ei is described with reference to FIG. 13 . A configuration of the post-treatment liquid output unit 72 Epp is basically the same as the configuration of the image output unit 72 Ei, so that a description thereof is omitted.

As shown in FIG. 13 , the image output unit 72 Ei includes an output control unit 72 Eic. The output control unit 72 Eic outputs print image data about each color to the corresponding discharge heads 40 C, 40 M, 40 Y, and 40 K ( FIG. 4 ). Specifically, driving waveforms created by the logic circuits of the data management units 72 EC, 72 EM, 72 EY, and 72 EK are applied to the piezoelectric element 45 P that serves as a pressure generation unit in the discharge heads (first discharge units) 40 C, 40 M, 40 Y, and 40 K while timing of the driving waveforms is controlled by the output control unit 72 Eic. When the driving waveform is applied, the piezoelectric element 45 P is expanded or contracted. Force of expansion or contraction acts on ink within a pressure chamber 40 R from the piezoelectric element 45 P via the vibration plate 42 . When a pressure change occurs within the pressure chamber 40 R, ink droplets are discharged from the nozzles 40 N. In this manner, the output control unit 72 Eic can control an operation of the discharge head 40 C and the like based on the print image data (driving waveform).

Specifically, the output control unit 72 Eic individually controls a plurality of discharge heads 40 C and the like. Further, the output control unit 72 Eic may simultaneously control the plurality of discharge heads 40 C and the like using print image data (such as Ic in FIG. 13 ) that is input. Further, the output control unit 72 Eic may control the discharge heads 40 C and the like based on a control signal that is input from a control device (not shown). The output control unit 72 Eic may control the discharge head 40 C and the like based on an operation input by a user, for example.

In the same manner as in FIG. 13 , the post-treatment liquid output unit 72 Epp includes an output control unit. The output control unit outputs post-treatment data to the head 50 ( FIG. 4 , second discharge unit). Specifically, driving waveforms created by a logic circuit of the data management unit 72 EP are applied to the piezoelectric element 45 P of the head 50 while timing of the driving waveforms is controlled by an output control unit. Ink droplets are discharged from the nozzles 50 N in accordance with a pressure change having occurred within the pressure chamber 40 R via the vibration plate 42 . The output control unit can control an operation of the head 50 based on the post-treatment liquid discharge data Ip (driving waveforms).

Further, as mentioned above, as a part of a position movement recovery operation, positional information is input and controlled such that the image formation unit (image output unit) 40 and the post-treatment unit (post-treatment liquid output unit) 50 are moved vertically for maintenance and recovery by the position movement units when printing is not being performed.

In accordance with this, the printer device 72 according to the present embodiment uses the data management unit 72 EC and the output control unit 72 Eic to input print image data output from the higher-level device 71 to the plurality of discharge heads 40 C and the like. In this case, the printer device 72 can control a set of the print image data about each color independently of other sets of the print image data. Further, the printer device 72 can easily change a configuration of the printer engine 72 E in accordance with a number of colors of the print image data (such as C, M, Y, and K or only K) or a number of discharge heads. In other words, the printer device 72 provides advantageous effects on size reduction and low cost of an apparatus by installing therein only the data management unit 72 EC and the like and the discharge head 40 C and the like that are required.

In the printer device 72 according to the present embodiment, if full-color printing is to be performed with four colors such as K, C, M, and Y, the data management unit 72 EC and the like can be disposed on the printer engine 72 E. In accordance with this, the printer device 72 can use the output control unit 72 Eic to connect each output from the data management unit 72 EC and the like to the corresponding discharge head 40 C and the like.

Further, in the printer device 72 , if printing is to be performed with a single color such as K, only a single data management unit 72 EK and the discharge head 40 K can be disposed to give priority to cost reduction of an apparatus. In accordance with this, the printer device 72 can use the output control unit 72 Eic to connect an output of the data management unit 72 EK to the discharge head 40 K.

Or, if printing is to be performed with a single color such as K, one data management unit 72 EK and four discharge heads may be disposed to give priority to printing speed. In accordance with this, the image formation apparatus 100 can use the output control unit 72 Eic to connect the output of the data management unit 72 EK to each of the four discharge heads. In this case, the image formation apparatus 100 can print by overlapping (superposing) the same color (K) plural times. Accordingly, it is possible to realize high-speed printing (image formation) four times faster as compared with a case where image formation is performed by a single discharge head.