WO2010114027A1 - Inkjet device, and ink fixing method using same - Google Patents

Abstract

An inkjet head (5) capable of ejecting ink droplets toward a recording medium (W), a heating device (6) to heat and fix the ink droplets landing on the recording medium (W), and an irradiation heat amount control unit (21) capable of controlling the amount of heat irradiated by the heating device (6) on the recording medium (W) depending on a picture area ratio of a picture drawn on the recording medium (W) are provided, and the irradiation heat amount control unit (21) increases the amount of irradiated heat in accordance with the increase of the picture area ratio. Thereby, the ink droplets landing on the recording medium (W) are preferably fixed, and the heating efficiency of the ink droplets can be improved.

Description

Ink jet device and ink fixing method using the same

The present invention relates to an ink jet apparatus that ejects ink droplets to land ink droplets on a drawing target, and an ink fixing method using the same.

Conventionally, as such an ink jet apparatus, an ink jet printer including an ink jet head for ejecting ink droplets and a heating lamp unit disposed in the immediate vicinity of the ink jet head is known (for example, see Patent Document 1). In this ink jet printer, ink droplets are ejected from an ink jet head and landed on a recording medium, and then the ink droplets landed on the recording medium are heated and cured by a heating lamp unit, thereby efficiently recording ink droplets. It is fixed on the medium.

JP 2008-279727 A

However, the amount of ink droplets ejected from the inkjet head is determined based on the drawing pattern drawn on the recording medium. In other words, the recording medium is formed with a portion where the ink droplet has landed and a portion where the ink droplet has not landed. Therefore, the discharge amount of the ink droplet discharged from the inkjet head is not always uniform. . At this time, the heating lamp unit heats the recording medium in order to cure the ink droplets that have landed on the recording medium. However, if the amount of heat irradiated from the heating lamp unit is constant, the heating medium does not need to be heated. It will heat up. For this reason, it is difficult to improve the heating efficiency for the recording medium of the heating lamp unit.

Conventionally, a technique for preheating a recording medium in advance before drawing in order to quickly fix ink droplets that have landed on the recording medium is also known, but the thermal conductivity, reflectance, and recording medium of the recording medium to be used are also known. Since the preheating condition of the recording medium changes depending on the pattern area ratio of the pattern drawn on the image, it is difficult to fix the ink droplets suitably.

Therefore, the present invention provides an ink jet apparatus capable of improving the heating efficiency of ink droplets while favorably fixing ink droplets that have landed on a drawing object, and an ink fixing method using the same. This is the issue.

An inkjet apparatus according to the present invention draws an ink jet head capable of ejecting ink droplets toward a drawing object, heating means for heating and solidifying the ink droplets that have landed on the drawing object, and drawing on the drawing object. Irradiation heat amount control means capable of controlling the amount of heat applied to the drawing object by the heating means in accordance with the pattern area ratio of the drawing pattern, and the irradiation heat amount control means is adapted to increase the pattern area ratio. It is characterized by increasing.

According to this configuration, the irradiation heat amount of the heating means can be controlled by the irradiation heat amount control means in accordance with the pattern area ratio of the drawing pattern drawn on the drawing object. Thereby, the irradiation heat amount control means can increase the irradiation heat amount when the pattern area ratio of the drawing pattern increases, and can decrease the irradiation heat amount when the pattern area ratio of the drawing pattern decreases. Accordingly, it is possible to provide an ink jet apparatus with good ink droplet heating efficiency while fixing ink droplets that have landed on a drawing object.

In this case, the drawing pattern has a high-rate pattern portion with a high pattern area ratio and a low-rate pattern portion with a low pattern area ratio, and the irradiation heat amount control means is based on the pattern area ratio averaged in the drawing pattern. It is preferable to derive the irradiation heat amount and fix the irradiation heat amount of the heating means so as to be the derived irradiation heat amount.

According to this configuration, it is possible to derive an irradiation heat amount with good heating efficiency from the averaged pattern area ratio, and it is possible to irradiate the derived irradiation heat amount toward the drawing target. Fixing can be suitably performed.

In this case, the drawing pattern has a high-rate pattern portion with a high pattern area ratio and a low-rate pattern portion with a low pattern area ratio, and the heating means draws by heating while scanning each pattern portion. It is preferable that the entire pattern can be heated, and the irradiation heat amount control means varies the irradiation heat amount of the heating means in accordance with the pattern area ratio of each pattern portion heated by the heating means.

According to this configuration, when the heating unit moves to the high rate pattern portion, the irradiation heat amount control unit increases the irradiation heat amount of the heating unit to heat the high rate pattern portion, while the heating unit changes to the low rate pattern portion. When moved, the irradiation heat amount control means can reduce the irradiation heat amount of the heating means and heat the low rate pattern portion. As a result, the amount of heat applied by the heating means can be varied as appropriate according to the pattern portion, so that the heating efficiency of the heating means can be improved, and ink droplets can be suitably fixed. .

In this case, it is preferable that the control of the irradiation heat amount by the irradiation heat amount control means is performed for each scanning of the inkjet head.

According to this configuration, since the irradiation heat amount can be controlled by the irradiation heat amount control unit every time the inkjet head is scanned, the irradiation heat amount can be controlled with high accuracy, thereby improving the heating efficiency of the heating unit. Further improvement can be achieved.

In this case, it is preferable that the irradiation heat quantity control means controls the irradiation heat quantity of the heating means based on printing conditions including the pattern area ratio.

According to this configuration, it is possible to control the irradiation heat amount of the heating means in consideration of printing conditions other than the pattern area ratio, so that the ink can be effectively fixed to the drawing object. In other words, printing conditions other than the pattern area ratio include the thermal conductivity, reflectance, and thickness of the recording medium. By taking these printing conditions into consideration, it is possible to more suitably fix the ink droplets. it can.

In this case, the heating unit heats the ink droplets that have landed on the drawing target after discharging the ink droplets by the inkjet head, and a preheating unit that can preheat the drawing target before discharging the ink droplets by the inkjet head. It is preferable to have post-heating means.

According to this configuration, it is possible to suitably fix the ink droplets by preheating the drawing object before landing by the preheating means and heating the ink droplets after landing by the postheating means.

In this case, it is preferable that the irradiation heat amount control means controls the preheating means and the postheating means so as to be switchable.

According to this configuration, the preheating means and the afterheating means can be switched by the irradiation heat amount control means. For this reason, for example, when the heating means heats the drawing object by reciprocating scanning, the preheating means precedes and the rear heating means follows in the forward operation, and the rear heating means precedes in the return operation. Although the preheating means follows, by switching between the preheating means and the postheating means at the time of the return operation, the preheating means can be advanced and the postheating means can be advanced at the time of the recovery operation.

In this case, it is preferable that the irradiation heat amount control means controls the whole irradiation heat amount by the heating means so as to be variable in a batch while maintaining the balance of the irradiation heat amount irradiated by the heating means to the drawing pattern.

According to this configuration, for example, even when the external environment such as the outside air temperature changes, the irradiation heat quantity can be changed in a batch while maintaining the balance of the irradiation heat quantity. It can be carried out.

According to the ink fixing method of the present invention, an ink ejection process for ejecting ink droplets from an inkjet head toward a drawing object and a drawing area ratio of the drawing picture drawn on the drawing object are applied to the drawing object. An ink fixing process that controls the amount of irradiated heat and heats and solidifies the ink droplets that have landed on the drawing object. In the ink fixing process, the amount of irradiated heat increases as the pattern area ratio increases. It is characterized by making it.

According to this configuration, it is possible to control the amount of irradiation heat applied to the drawing target according to the pattern area ratio of the drawing pattern drawn on the drawing target. Thereby, in the ink fixing step, when the pattern area ratio of the drawn pattern increases, the irradiation heat amount can be increased. On the other hand, when the pattern area ratio of the drawn pattern decreases, the irradiation heat amount can be decreased. Accordingly, it is possible to provide an ink fixing method with good heating efficiency of ink droplets while making it preferable to fix ink droplets that have landed on the drawing object.

According to the ink jet apparatus of the present invention and the ink fixing method using the same, it is possible to improve the heating efficiency of the ink droplets while making the fixing of the ink droplets landed on the drawing object suitable.

FIG. 1 is a schematic configuration diagram schematically illustrating the ink jet apparatus according to the first embodiment. FIG. 2 is a control block diagram of the ink jet apparatus according to the first embodiment. FIG. 3 is various graphs showing increase / decrease of irradiation heat amount with respect to various printing conditions. FIG. 4 is a schematic configuration diagram schematically illustrating the ink jet apparatus according to the second embodiment.

Hereinafter, an ink jet apparatus according to the present invention and an ink fixing method using the same will be described with reference to the accompanying drawings. The present invention is not limited to the following examples. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

As shown in FIG. 1, the inkjet apparatus 1 according to the first embodiment draws (prints) a drawing pattern on a recording medium W by ejecting ink droplets onto a sheet-like recording medium W that is a drawing target. Is. The inkjet apparatus 1 includes a mounting table 4 on which a recording medium W is placed, an inkjet head 5 that ejects ink droplets toward the recording medium W, and a heating device 6 that solidifies the ink droplets ejected from the inkjet head 5 ( Heating means), an inkjet head 5 and a heating device 6 are mounted, and a head moving mechanism 7 for moving the inkjet head 5 and the heating device 6 to the X axis and the Y axis is provided. The inkjet head 5, the heating device 6, and the head moving mechanism 7 are comprehensively controlled by the control device 8.

The mounting table 4 is formed in a rectangular parallelepiped shape, and the recording medium W is mounted on the upper surface thereof. The head moving mechanism 7 includes a traverser 10 equipped with the inkjet head 5 and the heating device 6, an X-axis moving mechanism (not shown) that moves the traverser 10 in the X-axis direction with respect to the mounting table 4, and the inkjet head 5 and the traverser 10. The heating device 6 includes a Y-axis moving mechanism (not shown) that can move in the Y-axis direction.

The traverser 10 is disposed so as to span the mounting table 4, and an X-axis moving mechanism is provided between the traverser 10 and the installation surface. A Y-axis moving mechanism is provided between the traverser 10, the inkjet head 5, and the heating device 6. Accordingly, the head moving mechanism 7 can sub-scan the inkjet head 5 and the heating device 6 by moving the traverser 10 in the X-axis direction (sub-scanning direction) by the X-axis moving mechanism, and can also move the Y-axis. By moving the inkjet head 5 and the heating device 6 in the Y-axis direction (main scanning direction) by the mechanism, the inkjet head 5 and the heating device 6 can be main-scanned.

Further, the traverser 10 is provided with a head position detection sensor 12 capable of detecting the position of the inkjet head 5. The head position detection sensor 12 is connected to the control device 8, and the control device 8 is ejected from the inkjet head 5 based on the head position information of the inkjet head 5 detected by the head position detection sensor 12. While controlling the ejection timing of the ink droplets, the amount of irradiation heat of the heating device 6 is controlled.

The inkjet head 5 performs drawing on the recording medium W while being controlled by the control device 8 based on the pattern data of the drawing pattern drawn on the recording medium W. Note that a plurality of types of ink ejected from the inkjet head 5 are prepared, and are appropriately used depending on the material of the recording medium W.

The heating device 6 includes a pair of heaters 15 and 15 provided on both sides in the main scanning direction with the inkjet head 5 interposed therebetween, and the pair of heaters 15 and 15 is configured by, for example, a halogen lamp or the like. ing. One of the pair of heaters 15 and 15 is used as a preheating heater 15 (preheating means), and the other is used as a postheating heater 15 (postheating means). That is, the pair of heaters 15 and 15 are appropriately switched between preheating and postheating by the forward and backward operations of the inkjet head 5 that reciprocates in the main scanning direction. In other words, the heater 15 located on the leading side in the traveling direction with respect to the reciprocating inkjet head 5 is used as the preheating heater 15, while the heater 15 located on the trailing side in the traveling direction is used as the rear heater 15. Used as

The preheater 15 preheats the recording medium W prior to the ejection of ink droplets by the inkjet head 5. Then, by preheating the recording medium W by the preheating heater 15, solidification of ink droplets that land on the recording medium W can be promoted. On the other hand, after the ink is ejected by the inkjet head 5, the post-heater 15 is heated toward the recording medium W on which the ink droplet has landed. The ink droplets that have landed on the recording medium W can be solidified by post-heating the recording medium W by the post-heater 15. Thereby, it is possible to suitably fix the ink to the recording medium W.

At this time, the preheater 15 and the postheater 15 are connected to the control device 8, and the control device 8 uses the preheater 15 and the postheater heater based on the pattern data of the drawing pattern drawn on the recording medium W. 15 irradiation heat quantity is controlled.

Accordingly, when the recording medium W is placed on the mounting table 4 and drawing on the recording medium W is started, the ink jet apparatus 1 causes the head moving mechanism 7 to move the ink jet head 5 in the main scanning direction, thereby causing the ink jet head 5 to move forward. Thus, ink droplets are ejected onto the recording medium W. As a result, printing for one scan is performed on the recording medium W. Thereafter, the inkjet apparatus 1 moves the inkjet head 5 in the sub-scanning direction by the head moving mechanism 7 and then causes the inkjet head 5 to return in the main scanning direction. As a result, printing for one scan is performed on the recording medium W. That is, printing for two scans can be performed on the recording medium W by reciprocating the inkjet head 5 in the main scanning direction. At this time, one of the pair of heaters 15, 15 preheats the recording medium W prior to ink ejection by the inkjet head 5, and the other after the ink ejection by the inkjet head 5, the ink droplets The recording medium W that has landed is heated.

Next, the control device 8 will be described. The control device 8 includes a drawing control unit 20 that controls drawing by the inkjet head 5 and an irradiation heat amount control unit 21 that controls irradiation heat amount by the pair of heaters 15 and 15. And. The control device 8 also includes a management control unit 22 that can input and output drawing pattern image data and various printing conditions, and a heater that stores a plurality of heater operation setting data for controlling the irradiation heat amount by the irradiation heat amount control unit 21. And a setting database 23.

The management control unit 22 is configured by a so-called computer, and receives image data of a drawing pattern to be drawn on the recording medium W, and various types of printing such as the type of ink to be used and the material and thickness of the recording medium W. It is configured to be able to input conditions. Further, the management control unit 22 generates head drive data for driving the inkjet head 5 based on the input pattern data and various printing conditions, and controls the irradiation heat amount of the pair of heaters 15 and 15. The heater operation setting data for this is appropriately selected from the heater setting database 23.

The drawing control unit 20 is connected to the head position detection sensor 12 and the management control unit 22 and is connected to the inkjet head 5 so as to be controllable. That is, the drawing control unit 20 discharges ink droplets discharged from the inkjet head 5 based on the head position information detected by the head position detection sensor 12 and the head drive data generated by the management control unit 22. Etc. are controlled.

The irradiation heat amount control unit 21 is connected to the head position detection sensor 12 and the heater setting database 23, and is connected to the pair of heaters 15 and 15 so as to be controllable. That is, the irradiation heat quantity control unit 21 applies the recording medium W by the pair of heaters 15 and 15 based on the head position information detected from the head position detection sensor 12 and the heater operation setting data acquired from the heater setting database 23. The amount of irradiation heat is appropriately controlled.

Here, the irradiation heat quantity control unit 21 acquires the heater operation setting data from the heater setting database 23, and the heater operation setting data is optimized based on the pattern data and various printing conditions input to the management control unit 22. The one is selected. Hereinafter, a series of operations for acquiring the heater operation setting data from the heater setting database 23 will be specifically described.

When the pattern data and various printing conditions are input to the management control unit 22, the management control unit 22 derives the pattern distribution data and the pattern area ratio data from the pattern data of the drawn pattern. Here, the pattern area ratio is a line drawing ratio of a pattern per unit area. The closer to blank paper, the lower the pattern area ratio, and the darker the drawn pattern, the higher the pattern area ratio. Further, the pattern distribution is a data distribution of a high-rate pattern portion having a high pattern area ratio and a low-rate pattern portion having a low pattern area ratio in the drawn pattern. In other words, the management control unit 22 subdivides the drawing pattern and derives the data by deriving the pattern area ratio in each of the plurality of subdivided pattern parts. As shown in FIG. 3, the amount of preheated and postheated heat by the pair of heaters 15 and 15 increases as the pattern area ratio increases. This is because if the pattern area ratio is high, the amount of ink discharged per unit area increases, and a large amount of heat is required to solidify the ink.

The management control unit 22 makes it preferable to control the amount of heat applied by the pair of heaters 15 and 15 by considering various printing conditions in addition to the above-described pattern distribution data and pattern area ratio data.

As shown in FIG. 3, the various printing conditions include the thermal conductivity of the recording medium W, the infrared reflectance of the recording medium, the thickness of the recording medium W, and the like. The printing conditions are not limited to these, and for example, the moving speed of the inkjet head 5 and the type of ink used may be considered. When setting these various printing conditions, it is preferable to register a plurality of printing conditions as a group, and select and call the registered group. According to this configuration, operability by the user can be improved.

The amount of preheated and postheated heat by the pair of heaters 15 and 15 increases as the thermal conductivity of the recording medium W increases. This is because if the thermal conductivity is high, the amount of heat distributed by the recording medium W is fast, and the amount of heat necessary to keep the ink landing position at a predetermined temperature increases. At this time, the change rate of the irradiation heat amount in the post-heating is smaller than the change rate of the irradiation heat amount in the preheating. This is because the ink droplets land on the recording medium W, and thus the influence of the heat diffusion. This is because of the decrease.

Further, the amount of preheated and postheated heat by the pair of heaters 15 and 15 increases as the infrared reflectance of the recording medium W increases. This is because if the infrared reflectance is high, the amount of heat absorbed by the recording medium W is poor, and the amount of heat required is increased. At this time, the change rate of the irradiation heat amount in the post-heating is smaller than the change rate of the irradiation heat amount in the preheating. This is because the ink droplets land on the recording medium W, thereby improving the heat absorption. It is to do.

Furthermore, the amount of preheated and postheated irradiation heat by the pair of heaters 15 and 15 increases as the thickness of the recording medium W increases. This is because the heat quantity required to raise the temperature of the recording medium W increases as the thickness of the recording medium W increases. In addition, when the recording medium W is thin, if the irradiation heat amount is increased, the recording medium W is likely to be deformed. Therefore, the irradiation heat amount is reduced as the recording medium W is thinner.

Here, with reference to FIG. 2, a series of control flows in which the control device 8 controls the irradiation heat amount of the heating device 6 will be described. First, when the pattern data and various printing conditions are input to the management control unit 22 (S1), the management control unit 22 derives the pattern distribution data of the drawn pattern and the pattern area ratio data corresponding to the pattern distribution from the pattern data. (S2). Then, the management control unit 22 adds heater operation setting data for controlling the irradiation heat amount of the pair of heaters 15 and 15 based on various printing conditions in addition to the derived pattern distribution data and pattern area ratio data of the drawn drawing pattern. Is selected from the heater setting database 23, and the selected heater operation setting data is output to the irradiation heat quantity control unit 21 (S3). Subsequently, when the drawing control unit 20 controls the head moving mechanism 7 and the inkjet head 5 and drawing of the drawing pattern is started (S4), the irradiation heat quantity control unit 21 sets a pair based on the heater operation setting data. The heaters 15 and 15 are driven. Thus, when the preheating heater 15 that performs preheating of the pair of heaters 15 and 15 moves to the high-rate pattern portion of the drawing pattern, the preheating of the drawing medium is performed while increasing the amount of irradiation heat and preheating the recording medium W. When moving to the low rate pattern portion, the amount of irradiation heat is lowered and the recording medium W is preheated. Similarly to the preheating heater 15 described above, when the post-heater 15 that performs post-heating moves to the high-rate pattern portion of the drawing pattern, it increases the amount of irradiation heat and heats the ink droplets that have landed. When moving to the low rate pattern portion of the pattern, the amount of irradiation heat is lowered to heat the landed ink droplets. From the above, the heating device 6 can vary the amount of irradiation heat according to the pattern area ratio as the inkjet head 5 moves in the main scanning direction.

In addition, the heater setting database 23 stores the used heater operation setting data and the drawing result by the inkjet apparatus 1 as a learning value in association with each other, and uses the learning value when the same printing conditions are obtained. Then, the irradiation heat amount control of the heating device 6 may be executed.

Further, the irradiation heat quantity control unit 21 can collectively change the whole irradiation heat quantity by the pair of heaters 15 and 15 while maintaining the balance of the irradiation heat quantity irradiated by the pair of heaters 15 and 15 with respect to the drawing pattern. Can do. That is, the irradiation heat amount control unit 21 controls the pair of heaters 15 and 15 based on the pattern distribution data, the pattern area rate data, and the heater operation setting data. The amount of heat that is required changes. For this reason, the irradiation heat amount control unit 21 increases or decreases the amount of heat at a certain temperature or a certain ratio in a batch while maintaining the balance of the amount of irradiation heat by the pair of heaters 15 and 15 set based on each data. Thus, the ink droplet can be more suitably fixed.

According to the above configuration, the amount of heat applied by the heating device 6 can be controlled in accordance with the pattern area ratio of the drawn pattern. As a result, the amount of heat applied by the heating device 6 can be increased in the high rate pattern portion where the ink droplet discharge amount is large, while the heating device 6 is used in the low rate pattern portion where the ink droplet discharge amount is small. The amount of irradiation heat can be lowered. As a result, the ink droplet landing on the recording medium W can be suitably fixed, and the ink jet apparatus 1 having high heating efficiency for the ink droplet can be obtained.

In addition, since the amount of heat applied by the heating device 6 can be controlled in consideration of various printing conditions other than the pattern area ratio, the ink can be more effectively fixed to the recording medium W.

In the first embodiment, the irradiation heat amount control unit 21 changes the irradiation heat amount of the heating device 6 in consideration of the pattern distribution in the drawing pattern, but instead of this, the pattern area averaged in the drawing pattern. The irradiation heat amount of the heating device 6 may be fixed so that the irradiation heat amount corresponds to the rate. Hereinafter, to be specifically described, the drawing pattern has a low rate pattern portion and an efficiency pattern portion, these pattern area rates are averaged, the amount of irradiation heat corresponding to the averaged pattern area rate, Derived from the graph shown in FIG. Then, the storage medium W may be heated by fixing the irradiation heat amount of the pair of heaters 15 and 15 of the heating device 6 so that the derived irradiation heat amount is obtained. According to this configuration, since it is not necessary to vary the amount of irradiation heat of the pair of heaters 15 and 15, the configuration of the irradiation heat amount control unit 21 can be simplified.

In Example 1, the irradiation heat amount control unit 21 presets the control of the irradiation heat amount by the pair of heaters 15 and 15 based on the pattern distribution data, the pattern area rate data, and the heater operation setting data. Not limited to this, the irradiation heat amount control unit 21 performs real-time control of the irradiation heat amount by the pair of heaters 15 and 15 based on the pattern distribution data, the pattern area ratio data, and the heater operation setting data during printing by the inkjet head 5. For example, it may be performed each time the inkjet head 5 is scanned. According to this, the irradiation heat amount control unit 21 can control the irradiation heat amount by the pair of heaters 15 and 15 for each scan of the inkjet head 5, and therefore can accurately control the irradiation heat amount. The heating efficiency by the heating device 6 can be further improved.

Next, with reference to FIG. 4, the ink jet apparatus 50 according to the second embodiment will be described. Only different parts will be described in order to avoid duplicate descriptions. The inkjet apparatus 1 according to the first embodiment draws a drawing pattern on the recording medium W by moving the inkjet head 5 in the main scanning direction and the sub-scanning direction. The drawing pattern can be drawn on the recording medium W only by moving the line head 52 only in the main scanning direction. Hereinafter, the inkjet device 50 will be described.

The inkjet device 50 includes a moving table 51 on which the recording medium W is placed, an inkjet line head 52 that ejects ink droplets toward the recording medium W, and a heating device 53 that solidifies the ink droplets ejected from the inkjet head 5. And. The moving table 51, the inkjet line head 52, and the heating device 53 are comprehensively controlled by the control device 8.

The moving table 51 is formed in a rectangular shape, and the recording medium W is placed on the upper surface thereof. The moving table 51 is movable in the X-axis direction (main scanning direction). At this time, a medium position detection sensor 57 for detecting the position of the recording medium W is provided on the moving table 51. Based on the medium position information detected by the medium position detection sensor, the inkjet line head 52 and the heating The device 53 is controlled.

The inkjet line head 52 is disposed over the entire width direction (Y-axis direction) of the recording medium W, and is controlled to be drawn by the control device 8 based on the picture data of the drawing picture drawn on the recording medium W. Printing is performed on the recording medium W. Therefore, when the inkjet line head 52 is drawn, the inkjet line head 52 can draw on the entire surface of the recording medium W by moving the moving table 51 in the X-axis direction.

The heating device 53 includes a pair of heaters provided on both sides in the main scanning direction with the inkjet line head 52 interposed therebetween. Each heater group includes a plurality of heaters 15 in the longitudinal direction of the inkjet line head 52. It is configured by arranging in the direction over the entire width. One of the pair of heaters is used as a preheater heater group, and the other is used as a postheater heater group. At this time, the heater group positioned on the leading side in the traveling direction in which the inkjet line head 52 travels relative to the moving table 51 is used as a preheating heater group, while the heater group positioned on the trailing side in the traveling direction. Is used as a post-heater group.

At this time, the preheating heater group and the rear heating heater group are connected to the control device 8, and the control device 8 performs the preheating heater group and the rear heating heater based on the pattern data of the drawing pattern drawn on the recording medium W. The amount of irradiation heat is controlled individually.

Accordingly, when the recording medium W is placed on the moving table 51 and drawing by the ink jet apparatus 1 is started, the moving table 51 moves in the main scanning direction relative to the ink jet line head 52, and along with this movement, ink jetting is performed. The line head 52 ejects ink droplets. Thereby, the drawing pattern is drawn on the entire surface of the recording medium W only by the ink-jet line head 52 performing one scan. At this time, one of the pair of heater groups preheats the recording medium W prior to ink ejection by the inkjet line head 52, and the other after the ink ejection by the inkjet line head 52, ink droplets The recording medium W that has landed is heated.

Next, the control device 8 will be described. The control device 8 is configured in substantially the same manner as in the first embodiment, and the irradiation heat amount control unit 21 individually controls each heater 15 of the pair of heater groups. ing.

Therefore, when the pattern data and various printing conditions are input to the management control unit 22, the management control unit 22 derives the pattern distribution of the drawn pattern and the pattern area ratio corresponding to the pattern distribution from the pattern data. Then, the management control unit 22 sets heater operation setting data for controlling the amount of irradiation heat of the pair of heaters based on various printing conditions in addition to the derived pattern distribution of the drawn drawing pattern and the pattern area ratio. Output from the database 23 toward the irradiation heat quantity control unit 21. Then, when the drawing control unit 20 controls the moving table 51 and the inkjet line head 52 and printing of the drawing pattern is started, the irradiation heat quantity control unit 21 sets a pair of heaters based on the heater operation setting data. Drive. Accordingly, when the preheating heater group that performs preheating of the pair of heaters moves to the high rate pattern portion of the drawing pattern, the irradiation heat amount is increased to preheat the recording medium W, while the drawing pattern has a low rate. When moved to the pattern portion, the amount of irradiation heat is lowered and the recording medium W is preheated. Similarly to the preheating heater 15, the post-heater group that performs post-heating, when moved to the high-rate picture portion of the drawing picture, increases the amount of irradiation heat and heats the landed ink droplets, while drawing. When moving to the low rate pattern portion of the pattern, the amount of irradiation heat is lowered to heat the landed ink droplets.

Even in the above configuration, the amount of heat applied by the heating device 6 can be controlled in accordance with the pattern area ratio of the drawn pattern. As a result, the amount of heat applied by the heating device 6 can be increased in the high rate pattern portion where the ink droplet discharge amount is large, while the heating device 6 is used in the low rate pattern portion where the ink droplet discharge amount is small. The amount of irradiation heat can be lowered. As a result, the ink droplets that have landed on the recording medium W can be suitably fixed, and the ink jet device 50 with high ink droplet heating efficiency can be obtained.

In the second embodiment, the moving table 51 is used to move the recording medium W in the main scanning direction. However, instead of the moving table 51, a fixed table is used, and a roller is brought into rolling contact with the recording medium W. A configuration may be adopted in which only the recording medium W is moved in the main scanning direction by being rotated.

As described above, the ink jet device and the ink fixing method using the ink jet device according to the present invention are useful when ink is suitably fixed, and particularly suitable for improving the heating efficiency of ink droplets. Yes.

DESCRIPTION OF SYMBOLS 1 Inkjet apparatus 4 Mounting stand 5 Inkjet head 6 Heating apparatus 7 Head moving mechanism 8 Control apparatus 10 Traverser 12 Head position detection sensor 15 Heating heater 20 Drawing control part 21 Irradiation heat amount control part 22 Management control part 23 Heater setting database 50 Inkjet apparatus ( Example 2)
51 Moving Table 52 Inkjet Line Head 53 Heating Device (Example 2)
57 Medium position detection sensor W Recording medium

Claims (9)

An inkjet head capable of ejecting ink droplets toward a drawing object;
Heating means for heating and solidifying the ink droplets landed on the drawing object;
Irradiation heat amount control means capable of controlling the amount of heat applied to the drawing object by the heating means according to the pattern area ratio of the drawing pattern drawn on the drawing object,
The inkjet apparatus according to claim 1, wherein the irradiation heat amount control means increases the irradiation heat amount in accordance with an increase in the pattern area ratio. The drawing pattern has a distribution of a high rate pattern portion with a high pattern area rate and a low rate pattern portion with a low pattern area rate,
The irradiation heat amount control means includes
2. The irradiation heat amount is derived based on the pattern area ratio averaged in the drawing pattern, and the irradiation heat amount of the heating unit is fixed so as to be the derived irradiation heat amount. Inkjet device. The drawing pattern has a distribution of a high rate pattern portion with a high pattern area rate and a low rate pattern portion with a low pattern area rate,
The heating means is configured to be able to heat the entire drawing picture by heating while scanning each picture part,
The irradiation heat amount control means includes
The inkjet apparatus according to claim 1, wherein the amount of irradiation heat of the heating unit is varied in accordance with the pattern area ratio of each of the pattern portions heated by the heating unit. The inkjet apparatus according to any one of claims 1 to 3, wherein the irradiation heat quantity is controlled by the irradiation heat quantity control means for each scan of the inkjet head. The irradiation heat amount control means includes
5. The ink jet apparatus according to claim 1, wherein an irradiation heat amount of the heating unit is controlled based on printing conditions including the pattern area ratio. The heating means includes
Prior to ejection of ink droplets by the inkjet head, preheating means capable of preheating the drawing object;
6. The inkjet according to claim 1, further comprising a post-heating unit that heats the ink droplet that has landed on the drawing target after the ink droplet is discharged by the inkjet head. apparatus. The inkjet apparatus according to claim 6, wherein the irradiation heat amount control means controls the preheating means and the post-heating means to be switchable. The irradiation heat amount control means controls the whole irradiation heat amount by the heating means so as to be variable in a collective manner while maintaining a balance of the irradiation heat amounts irradiated by the heating means to the drawing pattern. The inkjet device according to any one of 1 to 7. An ink ejection process for ejecting ink droplets from an inkjet head toward a drawing object;
Ink fixing that controls the amount of irradiation heat applied to the drawing object in accordance with the pattern area ratio of the drawing picture drawn on the drawing object, and heats and solidifies the ink droplets that have landed on the drawing object A process,
In the ink fixing step, the amount of heat of irradiation is increased in accordance with an increase in the pattern area ratio.

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