Heating device, liquid ejection device, printing device

Abstract

To provide a heating device which reduces the insufficient heating, a device for discharging liquid, and a printer.SOLUTION: A heating device comprises: ultraviolet ray irradiation means 521 which irradiates a sheet material P being the heating target applied with liquid with the ultraviolet ray; and UV irradiation control means 801 which controls the output of each UV-LED523 of the ultraviolet ray irradiation means 521. The UV irradiation control means 801 performs control of emitting light at the first output W1 in which output of each UV-LED523 becomes the first intensity in a region excluding edges Ga1, Ga2 of a liquid adhesion region G of the sheet material P, emitting light at the second output W2 in which the output of each facing UV-LED523 becomes the second intensity stronger than the first intensity in the edges Ga1, Ga2, and making the output to the edges Ga1, Ga2 stronger than the output to the region excluding the edges Ga1, Ga2.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present invention relates to a liquid ejecting device and a printing device. [Background technology]

[0002] 2. Description of the Related Art Printing devices that apply a liquid to a print target to perform printing include those that irradiate an active energy ray such as ultraviolet light onto a heating target to which the liquid has been applied, thereby heating and drying the heating target.

[0003] Conventionally, a partial curing station including at least one array of light-emitting diodes (LEDs) is known that partially cures ink to adjust the gloss of the ink, and each LED of each array of LEDs is individually addressable by varying the intensity of first radiation emitted from each LED as a substrate passes by the at least one array of LEDs, thereby adjusting the gloss of the ink (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2012-061853 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, heating by irradiation with active energy rays is performed by generating heat as the active energy rays are absorbed into the liquid, and heat is not generated in marginal areas where no liquid is attached (non-liquid-attached areas). Here, heat flows from areas of higher temperature to areas of lower temperature. Therefore, at the edge portion that is the boundary between the liquid-attached area and the non-liquid-attached area, there is a problem that the heat generated in the liquid-attached area escapes to the non-liquid-attached area, resulting in insufficient heating of the edge of the liquid-attached area.

[0006] The present invention has been made in view of the above problems, and has an object to reduce the occurrence of insufficient heating. [Means for solving the problem]

[0007] In order to solve the above problems, the heating device according to the present invention comprises: A means for irradiating the heating target to which the liquid has been applied with active energy rays; and a means for controlling the output of the irradiating means, The control means controls the output to be stronger for the edge of the liquid adhering area of ​​the heating target than for the area other than the edge of the liquid adhering area. The composition was as follows.

[0008] According to the present invention, the occurrence of insufficient heating can be reduced. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic explanatory diagram of a printing apparatus as a liquid ejecting apparatus according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view illustrating a discharge unit of the printing apparatus. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. 2 is a perspective view illustrating an example of an ultraviolet ray irradiation means. [Figure 6] FIG. 4 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in the first embodiment. [Figure 7] FIG. 11 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in the first embodiment. [Figure 8] FIG. 11 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in the first embodiment. [Figure 9] FIG. 11 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in a heating device according to a second embodiment of the present invention. [Figure 10]FIG. 11 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in a heating device according to a third embodiment of the present invention. [Figure 11] FIG. 11 is an explanatory diagram illustrating output control of an ultraviolet ray irradiation means in a heating device according to a fourth embodiment of the present invention. [Figure 12] FIG. 13 is an explanatory diagram illustrating output control of an ultraviolet ray irradiation means in a heating device according to a fifth embodiment of the present invention. [Figure 13] FIG. 11 is an explanatory diagram illustrating an example of an evaluation result regarding drying properties when heated by a heating device of a comparative example. [Figure 14] FIG. 13 is an explanatory diagram illustrating output control of ultraviolet radiation in a heating device according to a sixth embodiment of the present invention. [Figure 15] FIG. 13 is an explanatory diagram illustrating output control of ultraviolet radiation in a heating device according to a seventh embodiment of the present invention. [Figure 16] FIG. 13 is an explanatory diagram illustrating output control of ultraviolet radiation in a heating device according to an eighth embodiment of the present invention. [Figure 17] FIG. 13 is an explanatory diagram illustrating output control of ultraviolet radiation in a heating device according to a ninth embodiment of the present invention. [Figure 18] FIG. 23 is an explanatory diagram illustrating output control of ultraviolet radiation in a heating device according to a tenth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. A printing apparatus as a liquid ejecting apparatus according to a first embodiment of the present invention will be described with reference to Figures 1 and 2. Figure 1 is a schematic explanatory diagram of the printing apparatus, and Figure 2 is a plan explanatory diagram of an ejection unit of the printing apparatus.

[0011] The printing device 1 includes an input section 10 for inputting the sheet material P, a pre-treatment section 20 which is an application section, a printing section 30, a first drying section 40, a second drying section 50, an inversion mechanism section 60, and an output section 70.

[0012] The printing device 1 applies (coats) a pretreatment liquid as a coating liquid to the sheet material P transported (supplied) from the transport section 10 in the pretreatment section 20 as necessary, and then applies the required liquid to the sheet material P in the printing section 30 to perform the required printing.

[0013] Then, the printing device 1 dries the liquid adhering to the sheet material P in the first drying section 40 and the second drying section 50, and then discharges the sheet material P to the discharge section 70 via the inversion mechanism section 60, either as is or after printing on both sides of the sheet material P.

[0014] The loading section 10 includes an input tray 11 (lower input tray 11A, upper input tray 11B) that stores multiple sheet materials P, and a feeding device 12 (12A, 12B) that separates and sends out the sheet materials P one by one from the input tray 11, and supplies the sheet materials P to the pre-processing section 20.

[0015] The pre-treatment section 20 includes, for example, an application section 21 which is a treatment liquid application section that applies a treatment liquid having an effect of agglomerating ink and preventing show-through to the printing surface of the sheet material P.

[0016] The printing unit 30 includes a drum 31 which is a support member (rotating member) that supports the sheet material P on its circumferential surface and rotates, and a liquid ejection unit 32 which ejects liquid toward the sheet material P supported by the drum 31.

[0017] The printing section 30 includes a transfer cylinder 34 which receives the sheet material P sent from the pre-treatment section 20 and transfers the sheet material P between the drum 31, and a transfer cylinder 35 which receives the sheet material P transported by the drum 31 and transfers it to the first drying section 40.

[0018] The sheet material P transported from the pre-processing section 20 to the printing section 30 has its leading edge gripped by a gripping means (sheet gripper) provided on the transfer cylinder 34, and is transported as the transfer cylinder 34 rotates. The sheet material P transported by the transfer cylinder 34 is delivered to the drum 31 at a position opposite to the drum 31.

[0019] A gripping means (sheet gripper) is also provided on the surface of the drum 31, and the leading end of the sheet material P is gripped by the gripping means (sheet gripper). A plurality of suction holes are formed in a dispersed manner on the surface of the drum 31, and the suction means generates a suction airflow that flows inward from the required suction holes of the drum 31.

[0020] Then, the sheet material P transferred from the transfer cylinder 34 to the drum 31 has its leading edge gripped by the sheet gripper, and is adsorbed and supported on the drum 31 by the suction airflow of the suction means, and is transported as the drum 31 rotates.

[0021] The liquid discharge section 32 includes discharge units 33 (33A to 33E) which are liquid discharge means serving as liquid application means. For example, the discharge unit 33A discharges cyan (C) liquid, the discharge unit 33B discharges magenta (M) liquid, the discharge unit 33C discharges yellow (Y) liquid, the discharge unit 33D discharges black (K) liquid, and the discharge unit 33E discharges white (W) liquid. In addition, a discharge unit that discharges a special liquid such as gold (silver) can also be used.

[0022] The ejection unit 33 has a head module 100 including a full-line head in which a plurality of liquid ejection heads (hereinafter simply referred to as "heads") 101, each having a plurality of nozzle rows in which a plurality of nozzles 111 are arranged, are arranged in a staggered pattern on a base member 103, as shown in FIG.

[0023] The discharge operation of each discharge unit 33 of the liquid discharge section 32 is controlled by a drive signal corresponding to the printing information. When the sheet material P supported on the drum 31 passes through an area facing the liquid discharge section 32, liquid of each color is discharged from the discharge unit 33, and an image corresponding to the printing information is printed.

[0024] The first drying section 40 includes a heating means 42 such as an IR heater, and irradiates infrared rays to heat and dry the sheet material P to which the liquid has been applied and which is being transported by the transport section 41. The second drying section 50 includes a heating means 52 that irradiates ultraviolet rays as active energy rays, and irradiates ultraviolet rays to heat and dry the sheet material P to which the liquid has been applied and which has passed through the first drying section 40 and is being transported by the transport section 51. The transport sections 41 and 51 are configured as parts of the same transport means.

[0025] The reversing mechanism 60 includes a reversing section 61 that reverses the sheet material P using a switchback method when performing double-sided printing on the sheet material P that has passed through the first drying section 40 and the second drying section 50 and has had liquid applied to one side and been dried, and a double-sided conveying section 62 that sends the reversed sheet material P back upstream of the transfer drum 34 of the printing section 30.

[0026] The discharge section 70 includes a discharge tray 71 on which a plurality of sheet materials P are stacked. The sheet materials P conveyed from the reversing mechanism section 60 are successively stacked and held on the discharge tray 71.

[0027] In this embodiment, an example is described in which the sheet material is cut sheet material, but the present invention can also be applied to devices that use continuous bodies (webs) such as continuous paper or rolled paper, and devices that use sheet materials such as wallpaper.

[0028] Here, the liquid discharged from the discharge unit will be described.

[0029] The ejection units 33A to 33D eject water-based pigment inks that generate heat in the absorption wavelength range of ultraviolet light as active energy rays. That is, water-based pigment inks are used as the inks of the respective colors C, M, Y, and K (inks other than white).

[0030] A typical composition of aqueous pigment ink is about 90% water and other high boiling point solvents, about 5% resin, and about 5% pigment coloring material, but is not limited to this. Specific examples of pigment coloring materials that can be used include K carbon black, C copper phthalocyanine, M quinacridone, and Y monoazo yellow. By using such pigment coloring materials, it is possible to obtain vivid printed images that do not fade even when exposed to ultraviolet light, unlike inks that use dye coloring materials.

[0031] The ejection unit 33E ejects ultraviolet curable ink that initiates polymerization in the absorption wavelength range of ultraviolet light as active energy rays, that is, ultraviolet curable ink is used as the W ink (white ink).

[0032] UV-curable ink contains a UV-polymerization initiator and a UV-polymerizable monomer, and when irradiated with UV light, the polymerization initiator becomes active in a radical or cationic state, which reacts with the monomer, polymerizing the monomer and curing it as a resin. By using UV-curable ink for the white ink, cockling in the white area can be suppressed.

[0033] Next, an example of the heating device will be described with reference to Figures 3 and 4. Figure 3 is a side view of the heating device, and Figure 4 is a front view of the same.

[0034] The heating device 500 of the second drying section 50 has a transport mechanism section 501 which is a transport means, and an ultraviolet ray irradiation section 502 which is a heating means 52. The heating device 500 constitutes the second drying section 50.

[0035] The conveying mechanism 501 has a conveying belt 511 that carries and conveys the sheet material P. The conveying belt 511 is looped around a driving roller 512 and a driven roller 513 and moves in a circular motion. In this embodiment, the conveying mechanism 501 is a mechanism that conveys the sheet material P from the printing unit 30 to the reversing mechanism 60 as shown in FIG.

[0036] The conveyor belt 511 is a belt having a plurality of openings that are sucked by a suction chamber 514 disposed inside. For example, a mesh belt or a flat belt having suction holes is used. The suction chamber 514 performs suction using a suction blower, a fan, or the like. The conveyor is not limited to a conveyor using a suction method, and may be a conveyor that conveys the sheet material P using, for example, an electrostatic adsorption method or a gripper gripping method.

[0037] The ultraviolet ray irradiation section 502 includes a plurality of ultraviolet ray irradiation means 521 arranged along the conveying direction in a housing 503. The ultraviolet ray irradiation means 521 irradiates the sheet material P conveyed by the conveying mechanism section 501 with ultraviolet rays to heat it.

[0038] As shown in FIG. 3, the housing 503 is arranged with a gap between it and the conveyor belt 511 in the direction along the conveying direction, and as shown in FIG. 4, in the direction perpendicular to the conveying direction, the housing 503 has a portion 503a that extends below the conveyor belt 511 in the height direction.

[0039] Next, an example of the ultraviolet ray irradiation means will be described with reference to Fig. 5. Fig. 5 is a perspective explanatory view of the example of the ultraviolet ray irradiation means.

[0040] The ultraviolet irradiation means 521 has granular UV-LEDs 523 arranged in a lattice pattern on an irradiation surface 522. When each UV-LED 523 is caused to emit light with the same illuminance (intensity), the light is emitted uniformly overall along the irradiation surface 522. The ultraviolet light (UV light) used has a peak wavelength of 395 nm and a wavelength distribution with a full width at half maximum of approximately 15 nm.

[0041] Next, heating by the ultraviolet ray irradiation means 521 will be described.

[0042] Process color pigment inks such as black, cyan, magenta, and yellow, and special color pigment inks such as orange, green, and violet, have absorption wavelengths in the ultraviolet wavelength range (380 to 400 nm) and generate heat.

[0043] Therefore, by irradiating the aqueous pigment ink applied to the sheet material P with ultraviolet light of a wavelength (380 to 400 nm) from the ultraviolet irradiation means 521, the ink generates heat by acting on the absorption wavelength range of the coloring material in the aqueous pigment ink and the composition in the ink, thereby heating and drying the ink.

[0044] On the other hand, when an aqueous pigment ink is used for white, the coloring material in the aqueous pigment ink and the composition in the ink have low absorption (high reflectance) in the ultraviolet absorption wavelength region (380 to 400 nm), so heat generation is difficult and drying is insufficient. Also, white ink is mainly used as the white part of an image on non-white media.

[0045] In other words, since the water-based pigment-based white ink absorbs less ultraviolet light and does not generate heat, it is slow to dry, which can cause problems such as soiling the transport path and adhering and sticking to overlapping sheet materials after ejection, causing the image to peel off when the sheet materials P are separated.

[0046] Therefore, in this embodiment, ultraviolet curable ink is used for white. By using ultraviolet curable ink, the monomer undergoes a polymerization reaction when ultraviolet light in the absorption wavelength range (380 to 400 nm) is irradiated by the ultraviolet irradiation means 521, and the ink becomes hardened and dried.

[0047] As a result, even when white ink is used, an image can be obtained in which cockling does not occur in the white portion, and the inside of the conveying path is prevented from being soiled with undried ink.

[0048] In addition, the ultraviolet ray irradiation means 521 used for drying is a single unit that can act on both water-based pigment inks (black, cyan, magenta, yellow, orange, green, violet) and white ink, leading to miniaturization and cost reduction of the device.

[0049] Next, returning to FIG. 3, the portion relating to the output control of the ultraviolet ray irradiation means will be described.

[0050] In this embodiment, the multiple UV-LEDs 523 arranged in a grid pattern in the ultraviolet ray irradiation means 521 are capable of controlling the output (ON / OFF and adjustment of the amount of light (illuminance or intensity)) on a UV-LED basis in the direction (width direction) perpendicular to the transport direction of the sheet material P.

[0051] In addition, the multiple UV-LEDs 523 arranged in a grid pattern in the ultraviolet ray irradiation means 521 can be configured to control the output (ON / OFF and adjustment of light amount (illuminance or intensity)) on a group basis in a direction (width direction) perpendicular to the transport direction of the sheet material P, with a predetermined number of UV-LEDs being grouped together.

[0052] The UV irradiation control means 801 is a means for controlling the output of the ultraviolet ray irradiation means, and controls the output of each UV-LED 523 of each ultraviolet ray irradiation means 521 based on the detection results of the edge detection means 802 and the detection results of the sheet material detection means 803.

[0053] The edge detection means 802 receives image data and printing conditions, and detects the edge of the image (liquid-adhered area) on the sheet material P. The sheet material detection means 803 detects the leading edge of the sheet material P.

[0054] The UV irradiation control means 801 causes each UV-LED 523 of the ultraviolet ray irradiation means 521 facing the area excluding the edge of the liquid adhering area of ​​the sheet material P to be heated to emit light at a first output W1 which is a first intensity (illuminance). Also, the UV irradiation control means 801 causes each UV-LED 523 of the ultraviolet ray irradiation means 521 facing the edge of the liquid adhering area of ​​the sheet material P to be heated to emit light at a second output W2 which is a second intensity (illuminance) stronger than the first intensity. Note that control can also be performed on a group basis as described above.

[0055] That is, the UV irradiation control means 801 as a control means controls the output to the edge of the liquid adhering area of ​​the sheet material P so as to be stronger than the output to the area other than the edge of the liquid adhering area.

[0056] Next, the output control of the ultraviolet ray irradiation means in this embodiment will be described with reference to Fig. 6 to Fig. 8. Fig. 6 to Fig. 8 are explanatory diagrams for the same description, in which (a) is a plan view of the sheet material, and (b) or (c) is an explanatory diagram of the output of the ultraviolet ray irradiation means.

[0057] Here, a solid image is printed on a sheet material P, and the printed area of ​​this solid image is defined as the liquid adhering area G. In the liquid adhering area G, edges including the downstream and upstream edges of the sheet material P in the transport direction are defined as edge Ga1 and edge Ga2, respectively, and edges including the edge in the width direction perpendicular to the transport direction are defined as edge Gb1 and Gb2. The edges are predetermined areas including the edges of the liquid adhering area G, and in this embodiment, they are also the ends of the liquid adhering area.

[0058] First, the control of irradiating ultraviolet light to edge portions Ga1 and Ga2 on the downstream and upstream sides in the conveying direction of the sheet material P with the second output W2 will be described with reference to FIG.

[0059] 6(b), at time t1 when the leading edge of the sheet material P shown in FIG. 6(a) reaches the ultraviolet irradiation start position by the ultraviolet irradiation means 521, the UV irradiation control means 801 turns on the ultraviolet irradiation means 521 to emit light at the first output W1. By making the UV-LED 523 emit light at the first output W1, ultraviolet light of a first intensity is emitted (the same applies to the following explanation).

[0060] Then, at time t2 when edge Ga1 of liquid adhering area G of sheet material P reaches the ultraviolet ray irradiation position, UV irradiation control means 801 causes each UV-LED 523 of ultraviolet ray irradiation means 521 facing edge Ga1 to emit light at the second output W2. By causing the UV-LED 523 to emit light at the second output W2, ultraviolet rays of a second intensity are emitted (the same applies to the following explanation).

[0061] Then, at time t3 when edge Ga1 of liquid adhering area G of sheet material P passes the ultraviolet ray irradiation position, the UV irradiation control means 801 returns the output of each UV-LED 523 facing edge Ga1 to the first output W1, causing the ultraviolet ray irradiation means 521 to emit light at the first output W1.

[0062] Next, at time t4 when edge Ga2 of liquid adhering area G of sheet material P reaches the ultraviolet irradiation position, the UV irradiation control means 801 causes each UV-LED 523 of the ultraviolet irradiation means 521 facing edge Ga2 to emit light at the second output W2.

[0063] Then, at time t5 when edge Ga2 of liquid adhesion area G of sheet material P passes the ultraviolet ray irradiation position, the UV irradiation control means 801 returns the output of each UV-LED 523 facing edge Ga2 to the first output W1, causing the ultraviolet ray irradiation means 521 to emit light at the first output W1.

[0064] Then, at time t6 when the rear end of the sheet material P reaches the ultraviolet irradiation end position of the ultraviolet ray irradiation means 521, the UV irradiation control means 801 turns off the ultraviolet ray irradiation means 521.

[0065] In this way, ultraviolet light is irradiated to the liquid adhesion area G at a first output W1 that is a first intensity to the area excluding the edges Ga1, Ga2 on the downstream and upstream sides in the transport direction, and ultraviolet light is irradiated to the edges Ga1, Ga2 on the downstream and upstream sides in the transport direction at a second output W2 that is a second intensity stronger than the first intensity. In other words, in the transport direction of the sheet material P, the output of the UV-LEDs 523 of the ultraviolet light irradiation means 521 to the edges Ga1, Ga2 of the liquid adhesion area G is stronger than the output to the inner area.

[0066] This allows sufficient heat generation at the edge portions Ga1, Ga2 on the downstream and upstream sides in the transport direction of the liquid adhesion region G, reducing insufficient heating.

[0067] Here, the timing of ON / OFF and output change of the ultraviolet ray irradiation means 521 by the UV irradiation control means 801 will be described.

[0068] The edge detection means 802 detects the distance from the leading edge (downstream end) of the sheet material P to the downstream end (edge) of the liquid adhesion area G, the distance in the transport direction of the liquid adhesion area G, the position of the widthwise edge of the liquid adhesion area G, or the distance from the widthwise edge of the sheet material P, based on image data and printing conditions, and provides the results to the UV irradiation control means 801.

[0069] The UV irradiation control means 801 calculates the time from when the leading edge of the sheet material P is detected by the sheet material detection means 803 to times t1 to t6 in Figure 6 based on information from the edge detection means 802, the timing when the leading edge of the sheet material P is detected by the sheet material detection means 803, and the conveying speed of the sheet material P.

[0070] For example, the time until the leading edge position of the sheet material P is transported to the ultraviolet ray irradiation position, the time until the downstream end position (edge) of the edge Ga1 of the liquid adhering area G is transported to the ultraviolet ray irradiation position, and the time the edge Ga1 of the liquid adhering area G is transported to the ultraviolet ray irradiation position are calculated. Also, the time until the downstream end position (edge) of the edge Ga2 of the liquid adhering area G is transported to the ultraviolet ray irradiation position, and the time the edge Ga2 of the liquid adhering area G is transported to the ultraviolet ray irradiation position are calculated.

[0071] Then, based on the calculated time, at time points t1 to t6, the UV irradiation control means 801 turns on / off and changes the output of each UV-LED 523 of the ultraviolet ray irradiation means 521. Note that, although an example of time-based management is described here, it is also possible to detect the leading edge on the conveyor belt 511, detect the moving distance of the conveyor belt 511 with an encoder, and turn on / off and change the output of each UV-LED 523 of the ultraviolet ray irradiation means 521 at the distance corresponding to time points t1 to t6.

[0072] Next, the control of irradiating the widthwise edge portions Gb1 and Gb2 of the sheet material P with ultraviolet light at the second output W2 will be described with reference to FIGS.

[0073] In the direction along the conveying direction of the sheet material P shown in Fig. 7(a), the output of each UV-LED 523 of the ultraviolet ray irradiation means 521 facing the edge portion Gb (Gb1, Gb2) of the liquid adhering area G is controlled as shown in Fig. 7(b). In contrast, the output of each UV-LED 523 of the ultraviolet ray irradiation means 521 facing the area of ​​the liquid adhering area G of the sheet material P excluding the edge portion Gb is controlled as shown in Fig. 7(c). Also, in the width direction perpendicular to the conveying direction of the sheet material P shown in Fig. 8(a), the output of each UV-LED 523 of the ultraviolet ray irradiation means 521 is controlled as shown in Fig. 8(b).

[0074] In other words, in the region of the edge Gb of the liquid adhesion area G, as shown in Figure 7 (b), at the time t1 when the leading edge of the sheet material P reaches the ultraviolet irradiation start position, the UV irradiation control means 801 turns on each UV-LED 523 of the ultraviolet irradiation means 521 facing the edge Gb, causing them to emit light at the first output W1.

[0075] 8(b), the UV irradiation control means 801 causes each UV-LED 523 of the ultraviolet irradiation means 521 facing the edge Gb to emit light at the second output W2. At this time, the range of the UV-LED 523 to be set to the second output W2 is determined based on a predetermined edge width determined in advance from the edge position in the width direction of the liquid adhesion area G given by the edge detection means 802.

[0076] Then, at the point t3 when the edge Gb of the liquid adhering area G of the sheet material P passes the ultraviolet ray irradiation position, the UV irradiation control means 801 returns the output of each UV-LED 523 of the ultraviolet ray irradiation means 521 facing the edge Gb to the first output W1, causing the ultraviolet ray irradiation means 521 to emit light at the first output W1.

[0077] Then, at time t4 when the rear end of the sheet material P reaches the ultraviolet irradiation end position by the ultraviolet irradiation means 521, the UV irradiation control means 801 turns off the output of each UV-LED 523 of the ultraviolet irradiation means 521 facing the edge portion Gb.

[0078] In contrast, in the area excluding the edge Gb of the liquid adhesion area G, as shown in Figure 7 (c), at time t1 when the leading edge of the sheet material P reaches the ultraviolet irradiation start position, the UV irradiation control means 801 turns on each UV-LED 523 of the ultraviolet irradiation means 521 facing the area excluding the edge Gb, and causes them to emit light at the first output W1.

[0079] Then, while maintaining this first output W1, at time t4 when the rear end of the sheet material P reaches the ultraviolet irradiation end position, the UV irradiation control means 801 turns off each UV-LED 523 of the ultraviolet irradiation means 521 that faces the area excluding the edge portion Gb.

[0080] In this way, ultraviolet light is irradiated to the liquid adhesion region G at a first output W1 having a first intensity to the region excluding the edges Gb1, Gb2 in the width direction perpendicular to the transport direction, and ultraviolet light is irradiated to the edges Gb1, Gb2 in the width direction at a second output W2 having a second intensity stronger than the first intensity. In other words, in the width direction perpendicular to the transport direction of the sheet material P, the output of the UV-LEDs 523 of the ultraviolet light irradiation means 521 to the edges Gb1, Gb2 of the liquid adhesion region G is stronger than the output to the inner region.

[0081] This allows sufficient heat to be generated at the widthwise edge portions Gb1, Gb2 of the liquid adhesion area G, reducing insufficient heating.

[0082] By combining the above-mentioned control of the edges Ga1, Ga2 in the transport direction and the edges Gb1, Gb2 in the width direction of the liquid adhesion area G, ultraviolet light can be irradiated to the entire peripheral edge (edge) of the liquid adhesion area G with the second output W2.

[0083] Further, although an example in which the liquid adhesion area G is rectangular has been described here, even if the liquid adhesion area G has a shape other than rectangular, for example, if the outer shape is curved, ultraviolet light can be irradiated to the entire peripheral edge with the second output W2 in a similar manner by performing tracing control to select the UV-LED 523 that follows the edge and sets the second output W2.

[0084] Next, a second embodiment of the present invention will be described with reference to Fig. 9. Fig. 9 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in a heating device according to the second embodiment, where (a) is a plan view of a sheet material, and (b) is an explanatory diagram of the output of the ultraviolet ray irradiation means.

[0085] The control of irradiating ultraviolet light with the second output W2 onto the edge portion Ga1 and edge portion Ga2 on the downstream side and upstream side in the conveying direction of the sheet material P will be described below.

[0086] As shown in Figure 9(b), at time t1 when the leading edge of the sheet material P shown in Figure 9(a) reaches the ultraviolet irradiation start position, the UV irradiation control means 801 turns on each UV-LED 523 of the ultraviolet irradiation means 521, causing them to emit light at the first output W1.

[0087] Then, at time t2 prior to time t3 when edge Ga1 of liquid adhesion area G of sheet material P reaches the ultraviolet irradiation position, the UV irradiation control means 801 causes each UV-LED 523 of the ultraviolet irradiation means 521 facing edge Ga1 to emit light at the second output W2.

[0088] Here, the UV irradiation control means 801 changes the output of each UV-LED 523 facing the edge portion Ga1 of the ultraviolet irradiation means 521 at time t2, which is a predetermined time that is shorter than the time from when the sheet material detection means 803 detects the leading edge of the sheet material P to when the downstream end (edge) of the edge portion Ga1 is transported to the ultraviolet irradiation position.

[0089] Then, at time t4 when edge Ga1 of liquid adhering area G of sheet material P passes the ultraviolet ray irradiation position, the UV irradiation control means 801 returns the output of each UV-LED 523 facing edge Ga1 to the first output W1, causing the ultraviolet ray irradiation means 521 to emit light at the first output W1.

[0090] Next, at time t5 when edge Ga2 of liquid adhering area G of sheet material P reaches the ultraviolet irradiation position, the UV irradiation control means 801 causes each UV-LED 523 of the ultraviolet irradiation means 521 facing edge Ga2 to emit light at the second output W2.

[0091] Then, at time t7 after time t6 when edge Ga2 of the liquid adhesion area G of the sheet material P passes the ultraviolet ray irradiation position, the UV irradiation control means 801 returns the output of each UV-LED 523 facing edge Ga2 to the first output W1, and causes the ultraviolet ray irradiation means 521 to emit light at the first output W1.

[0092] Then, at time t8 when the rear end of the sheet material P reaches the ultraviolet irradiation end position of the ultraviolet ray irradiation means 521, the UV irradiation control means 801 turns off the ultraviolet ray irradiation means 521.

[0093] In this manner, in this embodiment, when ultraviolet light is irradiated at the second output W2 to the edges Ga1, Ga2 of the liquid adhering region G, ultraviolet light is irradiated at the second output W2 including the liquid non-adhering region adjacent to the liquid adhering region G. In other words, the output of the UV-LEDs 523 of the ultraviolet light irradiating means 521 to the region including the liquid non-adhering region adjacent to the edges Ga1, Ga2 of the liquid adhering region G is made stronger than the output to the region excluding the edges Ga1, Ga2 of the liquid adhering region G.

[0094] This allows ultraviolet light to be reliably irradiated to the edge of the liquid adhesion region G, including the edge, at the second output W2, and reduces insufficient heating of the edge.

[0095] Next, a third embodiment of the present invention will be described with reference to Fig. 10. Fig. 10 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in a heating device according to the third embodiment, where (a) is a plan view of a sheet material, and (b) is an explanatory diagram of the output of the ultraviolet ray irradiation means.

[0096] The control of irradiating ultraviolet light with the second output W2 onto the edge portion Ga1 and edge portion Ga2 on the downstream side and upstream side in the conveying direction of the sheet material P will be described.

[0097] As shown in Figure 10(b), at time t1 when the leading edge of the sheet material P shown in Figure 10(a) reaches the ultraviolet irradiation start position, the UV irradiation control means 801 turns on each UV-LED 523 facing the edge Ga1, causing them to emit light at the second output W2.

[0098] In other words, at time t1 before time t2 when edge Ga1 of the liquid adhesion area G of the sheet material P reaches the ultraviolet ray irradiation position, the UV irradiation control means 801 turns on each UV-LED 523 of the ultraviolet ray irradiation means 521 facing edge Ga1, causing them to emit light at the second output W2.

[0099] Here, the UV irradiation control means 801 turns on the ultraviolet irradiation means 521 from time t1 when the sheet material detection means 803 detects the leading edge of the sheet material P and the leading edge of the sheet material P is conveyed to the ultraviolet irradiation position.

[0100] Then, at time t3 when edge Ga1 of liquid adhering area G of sheet material P passes the ultraviolet ray irradiation position, the UV irradiation control means 801 returns the output of each UV-LED 523 of the ultraviolet ray irradiation means 521 facing edge Ga1 to the first output W1, causing the ultraviolet ray irradiation means 521 to emit light at the first output W1.

[0101] Next, at time t4 when edge Ga2 of liquid adhering area G of sheet material P reaches the ultraviolet irradiation position, the UV irradiation control means 801 causes each UV-LED 523 of the ultraviolet irradiation means 521 facing edge Ga2 to emit light at the second output W2.

[0102] Thereafter, at time t6 when the rear end of the sheet material P reaches the ultraviolet irradiation end position, the UV irradiation control means 801 turns off the output of the ultraviolet ray irradiation means 521.

[0103] In other words, until time t6 after time t5 when edge Ga2 of liquid adhesion area G of sheet material P passes the ultraviolet ray irradiation position, the UV irradiation control means 801 sets the output of each UV-LED 523 facing the end Ga2 to the second output W2, and irradiates ultraviolet ray at a second intensity stronger than the first intensity.

[0104] Thus, in this embodiment, when ultraviolet light is irradiated to the edges Ga1, Ga2 of the liquid adhesion area G at the second output W2, ultraviolet light is also irradiated to the liquid non-adhesion area adjacent to the liquid adhesion area G at the second output W2.

[0105] This ensures that the edge of the liquid adhesion region G is irradiated with ultraviolet light at the second output W2, thereby reducing insufficient heating of the edge. Also, the output of the UV-LED 523 is changed less frequently than in the second embodiment.

[0106] Next, a fourth embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in a heating device according to the fourth embodiment.

[0107] In this embodiment, the ultraviolet ray irradiation means 521 has a plurality of (9 in the figure) UV-LEDs 523 arranged in the width direction. Here, the UV-LEDs 523 that emit light at the first output W1 are shown as open rectangles (□), and the UV-LEDs 523 that emit light at the second output W2 are shown as filled rectangles (■).

[0108] Here, as shown in Figure 11(a), the downstream edge of the liquid adhering area G of the sheet material P is within the ultraviolet irradiation area of ​​the ultraviolet irradiation means 521, and at this time, each UV-LED 523 facing the downstream edge of the liquid adhering area G is made to emit light with the second output W2.

[0109] Then, after the edge of the liquid adhering area G has passed through the ultraviolet ray irradiation area, as shown in FIG. 11(b), each UV-LED 523 facing the edge of the liquid adhering area G in the width direction is caused to emit light with the second output W2.

[0110] Then, as shown in FIG. 11(c), when the upstream edge of the liquid attachment area G enters the ultraviolet ray irradiation area, the UV-LED 523 facing the upstream edge of the liquid attachment area G is caused to emit light with the second output W2.

[0111] The output of the UV-LEDs 523 of the ultraviolet ray irradiation means 521 in the transport direction and the output of the UV-LEDs 523 of the ultraviolet ray irradiation means 521 in the width direction can be controlled at the timings described in the first to third embodiments.

[0112] Next, a fifth embodiment of the present invention will be described with reference to Fig. 12. Fig. 12 is an explanatory diagram for explaining output control of an ultraviolet ray irradiation means in a heating device according to the same embodiment.

[0113] In this embodiment, the ultraviolet ray irradiation means 521 has a plurality of UV-LEDs 523 arranged in the width direction. Here, the UV-LEDs 523 that emit light at the first output W1 are also illustrated as open rectangles, and the UV-LEDs 523 that emit light at the second output W2 are also illustrated as filled rectangles.

[0114] In this embodiment, it is assumed that a liquid-adhered area G1 of a solid image and a liquid-adhered area G2 of a text image of, for example, "A," "B," and "C" are printed on the sheet material P.

[0115] 12(a), just before the liquid-adhered area G2 of the text image enters the ultraviolet ray irradiation area or from the leading edge of the text image (characters) in the transport direction, each UV-LED 523 facing the liquid-adhered area G2 is made to emit light with the second output W2. Each UV-LED 523 not corresponding to the liquid-adhered area G2 is made to emit light with the first output W1 or is kept OFF.

[0116] 12(b), when a character string is printed across multiple lines, the opposing UV-LEDs 523 are caused to emit light at the second output W2 during the section (transport direction) in which the character string is printed. Here, since the leading edge of the liquid attachment area G1 of the solid image enters the ultraviolet ray irradiation area, each of the UV-LEDs 523 (the upper four in FIG. 12(b)) that faces the downstream edge of the liquid attachment area G1 is also caused to emit light at the second output W2.

[0117] 12(c), when the liquid-adhered area G2 of the character string passes through the ultraviolet ray irradiation area, the UV-LEDs 523 corresponding to the liquid-adhered area G2 are switched to the first output W1 or OFF. Meanwhile, the UV-LEDs 523 facing the edges of the liquid-adhered area G1 in the width direction maintain the second output W2, and the UV-LEDs 523 facing the areas other than the edges of the liquid-adhered area G1 in the width direction are switched to the first output W1.

[0118] Thereafter, as shown in FIG. 12(d), the upstream edge of the liquid attachment area G1 enters the ultraviolet ray irradiation area, and the UV-LEDs 523 facing the upstream edge are caused to emit light with the second output W2.

[0119] Then, as shown in FIG. 12(e), after the liquid attachment regions G1 and G2 have passed through the ultraviolet ray irradiation region, each UV-LED 523 is set to the first output W1 or turned off.

[0120] In this manner, in this embodiment, the text is treated as the edge of the liquid-adhered region and irradiated with ultraviolet light at the second output, thereby preventing insufficient heating. Similarly, the line drawing is treated as the edge of the liquid-adhered region and irradiated with ultraviolet light at the second output, thereby preventing insufficient heating.

[0121] Next, the effects of the above embodiment will be described with reference to Fig. 13. Fig. 13 is an explanatory diagram for explaining an example of an evaluation result of drying property when heated by a heating device of a comparative example.

[0122] In the comparative example, the output of each UV-LED 523 of the ultraviolet irradiation means 521 is set constant, for example, to the first output W1, and ultraviolet rays are irradiated. Dryness evaluation was performed on the center and edge of the image, and the center and characters of the image when it passed through the heating device of this comparative example. The dryness evaluation was performed by checking the degree of peeling of the image after it was irradiated with ultraviolet rays and heated and dried, and the degree of clarity of the image was judged according to a unique evaluation standard.

[0123] Figure 13(a) shows the results of evaluating the center of the image and the image edges. The center of the image did not peel off (○), but the image edges peeled off (×). Also, because characters are lines, they are included in the image edges. When we performed the same evaluation as for the image edges, they peeled off just like the image edges, as shown in Figure 13(b).

[0124] Therefore, it was confirmed that by irradiating the edges including the image edges and characters with ultraviolet light at the second output with higher intensity as in the above embodiment, insufficient heating was eliminated and peeling was prevented.

[0125] Next, a sixth embodiment of the present invention will be described with reference to Fig. 14. Fig. 14 is an explanatory diagram for explaining output control of ultraviolet radiation in a heating device according to the sixth embodiment.

[0126] In this embodiment, as shown in FIG. 14(a), five ultraviolet ray irradiation means 521 are arranged along the sheet transport direction in the following order from the upstream side in the transport direction: ultraviolet ray irradiation means 521A, 521B, 521C, 521D, and 521E.

[0127] When ultraviolet light is irradiated from the most upstream ultraviolet irradiation means 521A, as shown in Figure 14(b), each UV-LED 523 is caused to emit light at the second output W2 at the edge of the liquid adhesion area G, and each UV-LED 523 is caused to emit light at the first output W1 in the area other than the edge.

[0128] In contrast, when ultraviolet light is irradiated from ultraviolet light irradiation means 521B-521E other than the most upstream ultraviolet light irradiation means 521A, each UV-LED 523 is made to emit light at the first output W1, including the edge of the liquid adhesion area G and the area excluding the edge, as shown in Figure 14(c).

[0129] Next, a seventh embodiment of the present invention will be described with reference to Fig. 15. Fig. 15 is an explanatory diagram for explaining output control of ultraviolet radiation in a heating device according to the seventh embodiment.

[0130] In this embodiment, as shown in FIG. 15(a), five ultraviolet ray irradiation means 521 are arranged along the sheet transport direction in the order of ultraviolet ray irradiation means 521A, 521B, 521C, 521D, and 521E from the upstream side in the transport direction.

[0131] When ultraviolet light is irradiated from the ultraviolet light irradiation means 521A-521E, as shown in Figures 15(b) and (c), each UV-LED 523 is caused to emit light at the second output W2 at the edge of the liquid adhesion area G, and each UV-LED 523 is caused to emit light at the first output W1 in the area other than the edge.

[0132] Next, an eighth embodiment of the present invention will be described with reference to Fig. 16. Fig. 16 is an explanatory diagram for explaining output control of ultraviolet radiation in a heating device according to the same embodiment.

[0133] In this embodiment, as shown in FIG. 16(a), five ultraviolet ray irradiation means 521 are arranged along the sheet transport direction in the order of ultraviolet ray irradiation means 521A, 521B, 521C, 521D, and 521E from the upstream side in the transport direction.

[0134] When ultraviolet light is emitted from the most upstream ultraviolet light irradiation means 521A, as shown in FIG. 16(b), each UV-LED 523 is caused to emit light with a first output W1.

[0135] Next, when ultraviolet light is irradiated from the ultraviolet irradiation means 521B, as shown in Figure 16 (c), each UV-LED 523 is caused to emit light at the second output W2 at the edge of the liquid adhesion area G, and each UV-LED 523 is caused to emit light at the first output W1 in the area other than the edge.

[0136] Furthermore, when ultraviolet rays are irradiated from the ultraviolet ray irradiation means 521C to 521E, each UV-LED 523 is caused to emit light with a first output W1, as in the ultraviolet ray irradiation means 521A, as shown in FIG. 16(b).

[0137] Next, a ninth embodiment of the present invention will be described with reference to Fig. 17. Fig. 17 is an explanatory diagram for explaining output control of ultraviolet radiation in a heating device according to the same embodiment.

[0138] In this embodiment, as shown in FIG. 17(a), five ultraviolet ray irradiation means 521 are arranged along the sheet transport direction in the order of ultraviolet ray irradiation means 521A, 521B, 521C, 521D, and 521E from the upstream side in the transport direction.

[0139] When ultraviolet rays are irradiated from the most upstream ultraviolet irradiation means 521A and the most downstream ultraviolet irradiation means 521E, as shown in Figures 17(b) and (f), each UV-LED 523 is made to emit light at the second output W2 at the edge of the liquid adhesion area G, and each UV-LED 523 is made to emit light at the first output W1 in the area other than the edge.

[0140] In contrast, when ultraviolet light is irradiated from the ultraviolet irradiation means 521B, 521C, and 521D, each UV-LED 523 is caused to emit light at the first output W1, including the edges of the liquid adhesion area G and the areas excluding the edges, as shown in Figures 17(c), (d), and (e).

[0141] Next, a tenth embodiment of the present invention will be described with reference to Fig. 18. Fig. 18 is an explanatory diagram for explaining output control of ultraviolet radiation in a heating device according to the same embodiment.

[0142] In this embodiment, as shown in FIG. 18(a), five ultraviolet ray irradiation means 521 are arranged along the sheet transport direction in the order of ultraviolet ray irradiation means 521A, 521B, 521C, 521D, and 521E from the upstream side in the transport direction.

[0143] When ultraviolet rays are irradiated from the ultraviolet irradiation means 521A, 521C, and 521E, as shown in Figures 18(b), (d), and (f), each UV-LED 523 is caused to emit light at the second output W2 at the edge of the liquid adhesion area G, and each UV-LED 523 is caused to emit light at the first output W1 in the area other than the edge.

[0144] On the other hand, when ultraviolet rays are irradiated from the ultraviolet irradiating means 521B and 521D, as shown in FIGS. 17(c) and 17(e), each UV-LED 523 is caused to emit light at the first output W1.

[0145] When multiple ultraviolet ray irradiation means are arranged in the transport direction as described above, the ultraviolet ray irradiation means that switches between the first output and the second output can be limited to a portion of the ultraviolet ray irradiation means. By switching the ultraviolet ray irradiation means that switches between the first output and the second output instead of fixing it, the multiple ultraviolet ray irradiation means can be used evenly.

[0146] In the present application, the liquid to be ejected may have a viscosity and surface tension that allows it to be ejected from the head, and is not particularly limited, but it is preferable that the viscosity of the liquid is 30 mPa·s or less at room temperature and pressure, or by heating or cooling. More specifically, the liquid may be a solution, suspension, emulsion, etc., containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a functionalizing material such as a polymerizable compound, a resin, or a surfactant, a biocompatible material such as DNA, amino acids, proteins, or calcium, an edible material such as a natural colorant, etc., and these can be used for applications such as inkjet ink, surface treatment liquid, a liquid for forming a component of an electronic element or a light-emitting element, an electronic circuit resist pattern, a material liquid for three-dimensional modeling, etc.

[0147] Energy sources for ejecting liquid include piezoelectric actuators (laminated piezoelectric elements and thin-film piezoelectric elements), thermal actuators that use electrothermal conversion elements such as heating resistors, and electrostatic actuators consisting of a vibration plate and an opposing electrode.

[0148] Furthermore, the term "device for ejecting liquid" includes not only devices capable of ejecting liquid onto objects to which the liquid can adhere, but also devices that eject liquid into air or liquid.

[0149] This "liquid ejecting device" can also include means for feeding, transporting, and discharging items onto which liquid can be attached, as well as pre-processing devices and post-processing devices.

[0150] For example, examples of "devices that eject liquid" include image forming devices that eject ink to form an image on paper, and three-dimensional modeling devices that eject modeling liquid onto a powder layer formed by layering powder in order to create a three-dimensional object (a three-dimensional model).

[0151] In addition, the term "liquid ejection device" is not limited to devices that use ejected liquid to visualize meaningful images such as letters and figures. For example, it also includes devices that form patterns that have no meaning in themselves and devices that create three-dimensional images.

[0152] The above-mentioned "object to which liquid can adhere" means an object to which liquid can adhere at least temporarily, and to which the liquid adheres and sticks, or to which the liquid adheres and penetrates, etc. Specific examples include media such as paper, recording paper, film, cloth, and other recording media, electronic boards, electronic components such as piezoelectric elements, powder layers, organ models, and test cells, and unless otherwise specified, includes all objects to which liquid can adhere.

[0153] The material of the above-mentioned "object to which liquid can adhere" may be any material to which liquid can adhere even temporarily, such as paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, and ceramics.

[0154] Furthermore, the "liquid ejection device" may be a device in which a liquid ejection head and an object to which liquid can be attached move relatively, but is not limited to this. Specific examples include a serial type device in which a liquid ejection head moves, a line type device in which a liquid ejection head does not move, etc.

[0155] Other examples of "liquid ejecting devices" include a treatment liquid application device that ejects a treatment liquid onto paper to apply the treatment liquid to the surface of the paper for purposes such as modifying the surface of the paper, and an injection granulation device that ejects a composition liquid in which raw materials are dispersed through a nozzle to granulate fine particles of the raw materials.

[0156] In the present application, the terms image formation, recording, printing, imprinting, printing, modeling, and the like are all synonymous. [Explanation of symbols]

[0157] 1 Printing device 10 Loading section 20 Pretreatment section 30 Printing Department 40 1st drying section 50 2nd drying section 60 Reversing mechanism 70 Unloading section 500 Heating device 501 Transport mechanism 502 UV irradiation unit 511 Conveyor belt 514 Suction chamber 521 Ultraviolet irradiation means 522 Irradiation surface 523 UV-LED 801 UV irradiation control means 802 Edge detection means

Claims

1. A means for irradiating the heating target to which the liquid has been applied with active energy rays; and a means for controlling the output of the irradiating means, The control means controls the output to be stronger for the edge of the liquid adhering area of ​​the heating target than for the area other than the edge of the liquid adhering area. A heating device characterized by:

2. In a direction perpendicular to a conveying direction of the heating object, the output to the edge of the liquid attachment area is made stronger than the output to the inner area.

2. The heating device according to claim 1 .

3. In the transport direction of the heating object, the output to the edge of the liquid attachment area is made stronger than the output to the inner area.

3. The heating device according to claim 1 or 2.

4. The output to a region including a liquid non-adhered region adjacent to an edge of the liquid adhering region is made stronger than the output to a region excluding the edge of the liquid adhering region.

4. The heating device according to claim 1, wherein the heating device is a heater.

5. A plurality of the irradiating means are arranged in the transport direction of the heating target, For some of the plurality of irradiating means, control is performed so that the output to the edge of the liquid adhering area is stronger than the output to the area other than the edge of the liquid adhering area.

5. The heating device according to claim 1, wherein the heating device is a heater.

6. The irradiating means arranged on the upstream side of the conveying direction of the heating target is controlled so that the output to the edge of the liquid adhering area is stronger than the output to the area other than the edge of the liquid adhering area.

6. The heating device according to claim 5.

7. When the liquid-attached region is at least one of text and line drawing, the output is strengthened.

7. The heating device according to claim 1, wherein the heating device is a heater.

8. A liquid applying means for applying a liquid to the sheet material; and a heating device according to any one of claims 1 to 7, which heats the sheet material as a heating target. A liquid ejection device comprising:

9. A liquid applying means for applying a liquid to the sheet material; and a heating device according to any one of claims 1 to 7, which heats the sheet material as a heating target. A printing device comprising:

Images