JP2010083139A - Fluid jet apparatus and image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form an image which can prevent forgery and duplication by a simple method. <P>SOLUTION: The fluid jet apparatus includes a jetting part which jets a colored fluid and a colorless fluid to a medium, an irradiation part which applies ultraviolet rays to the fluids on the medium and irradiates the fluids with first ultraviolet rays for hardening them and second ultraviolet rays smaller in energy than the first ultraviolet rays, and a control part for controlling the jetting action of fluids by the jetting part and the applying action of ultraviolet rays by the irradiation part. The control part makes the second ultraviolet rays applied to the colored fluid after the colored fluid is jetted to the medium, and makes the first ultraviolet rays applied to the colorless fluid after the colorless fluid is jetted on the colored fluid in a half hardening state with the second ultraviolet rays applied thereto. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a fluid ejecting apparatus and an image forming method.

As a fluid ejecting apparatus, an ink jet printer that prints an image by ejecting fluid (for example, ink) onto various media such as paper, cloth, and film is known.
Some printers include an ejecting unit that ejects ink (for example, colored ink) onto a medium, and an irradiation unit that irradiates the ink on the medium with ultraviolet rays. Then, by irradiating the ink jetted from the jetting unit and landing on the medium with ultraviolet rays, the ink is cured and an image is printed (see Patent Document 1).

JP 2006-110782 A

By the way, the printed matter printed by the printer described above may be easily forged or copied by a copying machine or the like. Thus, there is a demand for a proposal of a technique for preventing forgery and copying of printed matter.
SUMMARY An advantage of some aspects of the invention is that it forms an image capable of preventing forgery and duplication by a simple method.

In order to solve the above problems, the main present invention is:
An ejection unit that ejects a colored fluid and a colorless fluid onto a medium;
An irradiating unit for irradiating the fluid on the medium with ultraviolet rays, the irradiating unit for irradiating the first ultraviolet rays for curing the fluid and the second ultraviolet rays having energy smaller than the first ultraviolet rays;
A control unit for controlling a fluid ejection operation by the ejection unit and an ultraviolet irradiation operation by the irradiation unit;
After spraying the colored fluid onto the medium, the colored fluid is irradiated with the second ultraviolet light,
A controller that irradiates the colorless fluid with the colorless fluid after the colorless fluid is ejected onto the colored fluid that is irradiated with the second ultraviolet light and is semi-cured; and
A fluid ejecting apparatus comprising:

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is a block diagram illustrating an overall configuration of a printer. FIG. 2 is a diagram illustrating a configuration of a main part of the printer 1. FIG. 3 is a diagram illustrating a cross-sectional structure of a drum unit 30, a head unit 40, and an ultraviolet irradiation unit 50. FIG. 4A is a perspective view showing the head unit 40. 4B is a front view of the head 42 when the head 42 is viewed from the direction indicated by the arrow F in FIG. 4A. 3 is a perspective view of an ultraviolet irradiation unit 50. FIG. FIG. 6A is a schematic diagram for explaining an image easily forged. FIG. 6B is a schematic diagram for explaining an image for preventing forgery. 6 is a flowchart for explaining printing processing of an image for preventing forgery. 8A to 8J are schematic diagrams showing the state of ink on the paper S. FIG. FIG. 9A is a schematic diagram for explaining a comparative example. FIG. 9B is a schematic diagram for explaining the present embodiment.

  At least the following will be made clear by the description of the present specification and the accompanying drawings.

An ejection unit that ejects a colored fluid and a colorless fluid onto a medium;
An irradiating unit for irradiating the fluid on the medium with ultraviolet rays, the irradiating unit for irradiating the first ultraviolet rays for curing the fluid and the second ultraviolet rays having energy smaller than the first ultraviolet rays;
A control unit for controlling a fluid ejection operation by the ejection unit and an ultraviolet irradiation operation by the irradiation unit;
After spraying the colored fluid onto the medium, the colored fluid is irradiated with the second ultraviolet light,
A controller that irradiates the colorless fluid with the colorless fluid after the colorless fluid is ejected onto the colored fluid that is irradiated with the second ultraviolet light and is semi-cured; and
A fluid ejecting apparatus comprising:
According to such a fluid ejecting apparatus, the surface of the colored fluid is recessed by ejecting the colorless fluid onto the semi-cured colored fluid. Moreover, it becomes easy to form a convex by carrying out the main curing of the colorless fluid. For this reason, the three-dimensional image which has an unevenness | corrugation as a whole can be formed. Such a three-dimensional image can prevent counterfeiting and duplication.

In addition, such a fluid ejection device,
The control unit may eject the colorless fluid a plurality of times on the colored fluid that has been irradiated with the second ultraviolet rays and is in a semi-cured state, thereby laminating the colorless fluid.
In such a case, since the convexity of the transparent layer is increased by laminating a colorless fluid, a more stereoscopic image can be formed.

In addition, such a fluid ejection device,
The control unit alternately repeats the ejection of the colorless fluid onto the colored fluid that is irradiated with the second ultraviolet rays and is semi-cured and the irradiation of the first ultraviolet rays to the colorless fluid. Preferably, the colorless fluid is laminated on the colored fluid.
In such a case, by stacking the colorless fluid irradiated with the first ultraviolet ray, the height of the transparent layer can be easily managed, so that a three-dimensional image can be formed effectively.

In addition, such a fluid ejection device,
The controller is
Irradiation of the colorless fluid onto the colored fluid in a semi-cured state irradiated with the second ultraviolet rays, and then irradiating the colorless fluid with the first ultraviolet rays, thereby forming an uneven image. And
The magnitude of the energy of the second ultraviolet light can be changed,
It is desirable to adjust the size of the unevenness by changing the energy level of the second ultraviolet ray.
In such a case, forgery and duplication can be more effectively prevented because a larger variety of images can be formed by adjusting the size of the unevenness of the image by changing the energy level of the second ultraviolet ray.

In addition, such a fluid ejection device,
The control unit ejects the colorless fluid onto a part of the colored fluid that is irradiated with the second ultraviolet rays and is in a semi-cured state, and then the first fluid is applied to the colorless fluid and the colored fluid. It is desirable to irradiate with ultraviolet rays.
In such a case, a three-dimensional image can be formed with a small amount of colorless fluid as compared with the case where the colorless fluid is ejected onto all of the colored fluid.

Injecting a colored fluid onto the medium;
Irradiating the colored fluid on the medium with a second ultraviolet ray having lower energy than the first ultraviolet ray for curing the fluid;
Spraying a colorless fluid on the colored fluid that has been irradiated with the second ultraviolet rays and is in a semi-cured state;
Irradiating the colorless fluid on the colored fluid with the first ultraviolet light;
An image forming method comprising:
According to such an image forming method, an image capable of preventing forgery and duplication can be formed by a simple method.

=== Outline of inkjet printer ===
As an example of the fluid ejecting apparatus, an ink jet printer (hereinafter referred to as a printer 1) is taken as an example, and a configuration example and a print processing example of the printer 1 will be described.

<<< Configuration of Printer 1 >>>
FIG. 1 is a block diagram showing the overall configuration of the printer 1. FIG. 2 is a diagram illustrating a configuration of a main part of the printer 1. FIG. 3 is a diagram illustrating a cross-sectional structure of the drum unit 30, the head unit 40 which is an example of the ejection unit, and the ultraviolet irradiation unit 50. FIG. 4A is a perspective view showing the head unit 40. 4B is a front view of the head 42 when the head 42 is viewed from the direction indicated by the arrow F in FIG. 4A. FIG. 5 is a perspective view of the ultraviolet irradiation unit 50.

  The printer 1 that has received print data from the computer 110, which is an external device, controls each unit (feed / discharge unit 20, drum unit 30, head unit 40, ultraviolet irradiation unit 50, ink supply unit 60) by the controller 10, An image is formed on the paper S (printing process). The detector group 70 monitors the situation in the printer 1, and the controller 10 controls each unit based on the detection result.

  The controller 10 is a control unit (control unit) for controlling the printer 1. The interface unit 11 is for transmitting and receiving data between the computer 110 as an external device and the printer 1. The CPU 12 is an arithmetic processing unit for controlling the entire printer 1. The memory 13 is for securing an area for storing the program of the CPU 12 and a work area. The CPU 12 controls each unit by a unit control circuit 14 according to a program stored in the memory 13.

  As shown in FIG. 2, the paper supply / discharge unit 20 includes a paper supply unit 21 and a paper discharge unit 22. The paper feed unit 21 has a paper feed roller (not shown) that transports the paper S, and feeds the paper S stacked in the paper feed unit 21 to the drum unit 30 one by one. The paper discharge unit 22 has a paper discharge roller (not shown) that conveys the paper S, and feeds the paper S, which is supported on the drum unit 30 and has been printed, into the paper discharge unit 22.

  The drum unit 30 includes a holding drum 31 that holds the paper S fed from the paper feeding unit 21. The rotating shaft 32 of the holding drum 31 is rotatably supported by a pair of frames 36. The holding drum 31 rotates in the direction of the arrow R shown in FIG. 2 while holding the paper S on the outer peripheral surface 33.

  The head unit 40 includes a head carriage 41 supported by a pair of guide shafts 46 and 47 and capable of reciprocating in the axial direction of the holding drum 31. The head carriage 41 is provided with a head 42 that ejects ink, which is an example of fluid, onto the paper S. Here, in this embodiment, as the head 42, five heads 42a to 42e (FIG. 4B) that eject inks of different colors are provided so as to face the paper S held on the holding drum 31. ing. Each head 42a to 42e has nozzle plates 44a to 44e in which a plurality of nozzles are formed, and ink is ejected from each nozzle. Each nozzle is provided with a pressure chamber (not shown) containing ink and a drive element (piezo element) for changing the volume of the pressure chamber to eject ink.

  The head carriage 41 is provided with storage chambers 43a to 43e (FIG. 4A) for storing ink (specifically, pigment ink). Each of the storage chambers 43a to 43e stores ink supplied to the corresponding heads 42a to 42e. The storage chamber 43a supplies the clear ink supplied to the head 42a, the storage chamber 43b supplies the yellow ink supplied to the head 42b, the storage chamber 43c supplies the magenta ink supplied to the head 42c, and the storage chamber 43d supplies the head 42d. The storage chamber 43e stores the black ink supplied to the head 42e. The clear ink is a colorless and transparent fluid, and the yellow, magenta, cyan, and black inks are colored fluids (color inks). Thus, the head unit 40 ejects colored ink and colorless ink onto the paper S.

  In this embodiment, an ultraviolet curable ink that is cured when irradiated with ultraviolet rays is used as the ink. Here, the ultraviolet curable ink is prepared by adding an auxiliary agent such as an antifoaming agent or a polymerization inhibitor to a mixture of a vehicle, a photopolymerization initiator and a pigment. The vehicle is prepared by adjusting the viscosity of a photopolymerization-curing oligomer, monomer or the like with a reactive diluent. The ink includes both water-based ink and oil-based ink.

  The ultraviolet irradiation unit 50 includes an irradiation unit carriage 51 that is supported by a pair of guide shafts 56 and 57 and that can reciprocate in the axial direction of the holding drum 31. As shown in FIG. 3, the irradiation unit carriage 51 is provided with an irradiation unit 52 that irradiates the ink ejected from the head 42 and landed on the paper S with ultraviolet rays. The irradiation unit 52 includes a plurality of lamps 53 aligned along the rotation direction of the holding drum 31. For example, a metal halide lamp is used as the lamp 53. The plurality of lamps 53 irradiate the ink on the paper S with ultraviolet rays, so that the ink is cured.

  The irradiation unit 52 irradiates the first ultraviolet ray for curing the ink and the second ultraviolet ray having energy smaller than that of the first ultraviolet ray. The magnitude of the energy of the second ultraviolet ray is, for example, 3 to 5% of the magnitude of the energy of the first ultraviolet ray. For this reason, the ink irradiated with the first ultraviolet ray is almost completely cured (hereinafter also referred to as a “cured state”), whereas the ink irradiated with the second ultraviolet ray is not sufficiently cured (hereinafter referred to as a “half-cured state”). Also called cured state).

  When the amount of ink in the head unit 40 (specifically, the storage chambers 43a to 43e) is reduced due to the ejection of ink by the heads 42a to 42e, the ink supply unit 60 moves to the storage chambers 43a to 43e. It is for replenishing ink. The ink supply unit 60 includes ink cartridges 61a to 61e. The ink cartridges 61a to 61e store ink to be supplied to the corresponding storage chambers 43a to 43e (for example, the ink cartridge 61a stores clear ink to be supplied to the storage chamber 43a).

<<< Print processing >>>
Upon receiving a print command and print data from the computer 110, the controller 10 analyzes the contents of various commands included in the print data and performs the following print processing using each unit.

  First, the paper feeding unit 21 feeds the paper S toward the holding drum 31. The sheet S fed to the holding drum 31 is held by being wound around the outer peripheral surface 33. The held paper S rotates together with the holding drum 31. Each head 42 ejects ink to land on the rotating paper S. The ink that has landed on the paper S moves as the holding drum 31 rotates, and is irradiated with ultraviolet rays by the irradiation unit 52. As a result, the ink on the paper S is cured and an image is formed on the paper S.

  When an image is printed on the sheet S in a partial region in the axial direction of the holding drum 31 when the holding drum 31 rotates once, the head carriage 41 moves along the guide shafts 46 and 47 (irradiation unit carriage). 51 also moves along the guide shafts 56 and 57). Then, the above-described operations (ink ejection by the head 42 and ultraviolet irradiation by the irradiation unit 52) are performed on a region adjacent to the region in the axial direction.

  In this way, the paper S on which all images are printed in the axial direction of the holding drum 31 is peeled off from the holding drum 31 and sent to the paper discharge unit 22. As a result, the printing process ends.

=== Image for preventing counterfeiting ===
The printed matter printed by the printer may be easily duplicated or forged by a copying machine or the like. Therefore, the printer 1 according to the present embodiment prints an image for preventing forgery or the like that can prevent forgery or duplication of printed matter. In the following, first, an image that is easily forged or the like will be described, and then an image for preventing forgery or the like according to the present embodiment will be described.

  FIG. 6A is a schematic diagram for explaining an image that is easily forged. The image shown in FIG. 6A is formed by ejecting only the color ink and then irradiating the color ink with ultraviolet rays (first ultraviolet rays). That is, the image shown in FIG. 6A has only a color layer. The general printer ejects the ink so that the ink on the paper S (color ink constituting the color layer) is smoothed. For this reason, in such an image, the surface of the color layer is flat (in other words, no irregularities are formed on the surface of the color layer). Such a smooth image is easily duplicated and easily forged.

  FIG. 6B is a schematic diagram for explaining an image for preventing forgery or the like. This image for preventing forgery or the like is formed by a printing process described later. In the image shown in FIG. 6B, a recess is formed on the surface of the color layer made of the color ink, and a transparent layer made of the clear ink on the color layer forms a protrusion.

  Next, the reason why the image shown in FIG. 6B is difficult to duplicate and counterfeit will be described.

  First, by forming a recess on the surface of the color layer, the user or the like can feel the shadow of the image. On the other hand, when duplicating or the like, it is difficult to form a recess on the surface of the color layer (that is, the duplicated image is smooth), so that the shadow of the image cannot be felt. For this reason, an image for preventing forgery and a duplicate image can be identified. In particular, by changing the angle at which the two images are viewed, the shadows of the images become more conspicuous and can be identified more easily.

  In addition, since the convex is formed on the color layer with the clear ink, when the user touches the convex, a feeling of crushing is felt. On the other hand, in an image that is duplicated or the like, it is difficult for the convexity to be duplicated. For this reason, the two images can be identified by the feeling (whether or not there is a crushing feeling) when the image for preventing forgery and the duplicate image are touched.

=== Image Printing Processing for Preventing Forgery etc. ===
As an image forming method for printing the above-described image for preventing forgery or the like, the printer 1 executes a printing process described below.

  FIG. 7 is a flowchart for explaining an image printing process for preventing forgery or the like. 8A to 8J are schematic diagrams showing the state of ink on the paper S. FIG.

  The various operations of the printer 1 when this printing process is executed mainly control the ink ejection operation by the head unit 40 and the ultraviolet ray (first ultraviolet ray and second ultraviolet ray) irradiation operation by the irradiation unit 52. The controller 10 is implemented. In particular, this embodiment is realized by the CPU 12 processing a program stored in the memory 13. And this program is comprised from the code | cord | chord for performing the various operation | movement demonstrated below.

  The main features of this printing process are: (1) the color ink is ejected onto the paper S; and (2) the color ink on the paper S has a lower energy than the first ultraviolet rays for curing the ink. (2) irradiating the second ultraviolet light, (3) ejecting the clear ink onto the color ink that has been irradiated with the second ultraviolet light, and (4) applying the first ultraviolet light to the clear ink on the color ink. And irradiating.

  The controller 10 that has received an execution command (printing command) of an image printing process for preventing counterfeiting from the computer 110 first ejects color ink onto the paper S (step S2). That is, the head 42 ejects color ink onto the paper S held on the rotating holding drum 31 as shown in FIG. 8A. The ejected color ink lands on the paper S to form a smooth layer as shown in FIG. 8B.

  Then, the controller 10 further rotates the holding drum 31 that holds the paper S on which the color ink has landed, and irradiates the color ink on the paper S with the second ultraviolet rays (step S4). That is, the irradiation unit 52 irradiates the color ink on the paper S with the second ultraviolet ray as shown in FIG. 8C.

  By the way, as described above, the energy of the second ultraviolet ray is smaller than the energy of the first ultraviolet ray that cures the ink. For this reason, the color ink on the paper S irradiated with the second ultraviolet ray is in a semi-cured state.

  Next, the controller 10 rotates the holding drum 31 once, and as shown in FIG. 8D, the second ultraviolet ray is irradiated and the clear ink is ejected onto the semi-cured color ink (step S6). Specifically, the head 42 ejects clear ink onto a part of the color ink that is irradiated with the second ultraviolet rays and is semi-cured.

  Here, due to the impact when the clear ink lands on the semi-cured color ink, a recess is formed on the surface of the color layer composed of the semi-cured color ink as shown in FIG. 8E. That is, a part of the clear ink enters the surface of the color layer to form a recess.

  Further, the degree of semi-curing of the color ink irradiated with the second ultraviolet ray varies depending on the energy level of the second ultraviolet ray. That is, the smaller the energy of the second ultraviolet light, the harder the color ink is cured (that is, the degree of semi-curing of the color ink is greater). Then, when the clear ink lands on the semi-cured color ink, the greater the degree of semi-curing of the color ink, the more easily the concaves on the surface of the color layer are formed. Therefore, the smaller the energy of the second ultraviolet light, the larger the concave portion of the surface of the color layer (in contrast, the larger the energy of the second ultraviolet light, the smaller the concave portion of the surface of the color layer). Thus, the controller 10 can change the magnitude of the energy of the second ultraviolet ray, and adjusts the size of the unevenness of the image by changing the magnitude of the energy of the second ultraviolet ray.

  Next, as shown in FIG. 8F, the controller 10 irradiates the clear ink landed on the color ink with the first ultraviolet ray (step S8). As a result, the clear ink landed on the color is fully cured. Note that the controller 10 irradiates the first ultraviolet light not only to the clear ink but also to the color ink on which the clear ink has not landed. Thereby, the semi-cured color ink is also fully cured.

  Next, the controller 10 ejects the clear ink as shown in FIG. 8G (step S6) to further form a clear ink transparent layer on the color ink (step S10: No), and then, as shown in FIG. 8H. In this manner, the first ultraviolet ray is irradiated (step S8). As a result, a second transparent layer is formed.

  Thus, the controller 10 repeats the above steps S6 and S8 until the clear ink is ejected a predetermined number of times on the color ink. That is, as shown in FIGS. 8I and 8J, the controller 10 alternately performs the ejection of the clear ink onto the color ink that has been irradiated with the second ultraviolet ray and is semi-cured, and the irradiation with the first ultraviolet ray on the clear ink. The clear ink (specifically, the cured clear ink) is laminated on the color ink repeatedly.

  In this manner, the controller 10 causes the clear ink to be ejected a plurality of times on the color ink that has been irradiated with the second ultraviolet rays and is in a semi-cured state, thereby laminating the clear ink. A convex is formed on the color ink by the clear ink (transparent layer) laminated in this way.

  It should be noted that the head carriage 41 and the irradiation unit carriage 51 are located at the same position in the axial direction (FIG. 2) while the processes of steps S2 to S10 described above are being performed. That is, the color ink and the clear ink are ejected to the same region in the axial direction of the paper S, and ultraviolet rays are irradiated.

  If there is a region where an image is further printed on the paper S (step S12: Yes), the controller 10 moves the head carriage 41 and the irradiation unit carriage 51 in the axial direction, for example, in the axial direction already. The above-described operation (steps S2 to S10) is repeated for an area adjacent to the area where the print image P is printed. On the other hand, when there is no area to be printed (step S12: No), the controller 10 ends the first printing process. As a result, printing of an image (an image for preventing forgery or the like) for all areas of one sheet of paper S is completed.

  As described above, the controller 10 irradiates the first ultraviolet ray to the clear ink after ejecting the clear ink onto the color ink that is irradiated with the second ultraviolet ray and is in a semi-cured state. Prevention image).

=== Effectiveness of Printer 1 According to the Present Embodiment ===
In the above-described printing process, the controller 10 (control unit) (1) causes the color ink to be ejected onto the paper S and then irradiates the color ink with the second ultraviolet ray. After the clear ink is jetted onto the color ink, the clear ink is irradiated with the first ultraviolet rays. This makes it possible to form an image that can prevent forgery and duplication by a simple method.

  Hereinafter, the effectiveness of the printer 1 according to the present embodiment will be described while describing a comparative example. FIG. 9A is a schematic diagram for explaining a comparative example. FIG. 9B is a schematic diagram for explaining the present embodiment.

  In the comparative example shown in FIG. 9A, a transparent layer made of clear ink is laminated on a color ink (color layer) that has been cured by irradiation with the first ultraviolet rays. This is because clear ink is ejected after the color ink on the paper S is fully cured, so that the clear ink is laminated on the smooth color layer (a transparent layer forming a convex is formed). For this reason, while a three-dimensional image can be formed, it is difficult to feel a shadow like an image having a recess.

  On the other hand, in the case of the present embodiment, the clear ink is laminated on the color ink which is irradiated with the second ultraviolet ray and is semi-cured. Then, a recess is formed on the surface of the color layer by an impact when the clear ink is landed. Moreover, the transparent layer which comprises a convex is formed similarly to a comparative example. For this reason, a three-dimensional image that makes the user feel a crushing feeling when the user touches the image can be formed by the transparent layer constituting the convex, and the shadow of the image is caused by the concave of the surface of the color layer. .

  Therefore, according to the printer 1 according to the present embodiment, it is possible to form an image that can prevent forgery and duplication by a simple method.

Further, as described above, as shown in FIGS. 8A to 8J, the controller 10 stacks the clear ink by spraying the clear ink a plurality of times on the color ink that is irradiated with the second ultraviolet ray and is semi-cured. Let
In such a case, since the convexity of the transparent layer is increased by laminating clear ink, a more three-dimensional image can be formed. In FIG. 8, the clear ink is ejected a plurality of times at the same location, but there may be a portion where the clear ink is ejected only once at the same location. In that case, the convex shape becomes more diverse. Further, the clear ink may not be ejected a plurality of times in the same place, and the ink may be ejected only once. In this case, although the convex of the clear ink is reduced, the concave is formed in the color layer. 3D image formation is possible. In that case, the clear ink may be ejected once.

Further, as described above, the controller 10, as shown in FIGS. 8A to 8J, ejects the clear ink onto the color ink that is irradiated with the second ultraviolet ray and is semi-cured, and the first ultraviolet ray to the clear ink. The clear ink is repeated alternately, and the clear ink is laminated on the color ink.
In such a case, by stacking the clear ink irradiated with the first ultraviolet ray, the height of the transparent layer can be easily managed, so that a three-dimensional image can be effectively formed.

In addition, as described above, the controller 10 has the unevenness by irradiating the first ultraviolet ray to the clear ink after the clear ink is ejected onto the color ink that is irradiated with the second ultraviolet ray and is semi-cured. Form an image. And the controller 10 can change the magnitude | size of the energy of a 2nd ultraviolet-ray, and adjusts the magnitude | size of the unevenness | corrugation of the said image by changing the magnitude | size of the energy of a 2nd ultraviolet-ray.
In such a case, forgery and duplication can be more effectively prevented because a larger variety of images can be formed by adjusting the size of the unevenness of the image by changing the energy level of the second ultraviolet ray.

Further, as described above, the controller 10 irradiates the first ultraviolet light to the clear ink and the color ink after ejecting the clear ink onto a part of the color ink that is irradiated with the second ultraviolet light and is semi-cured. .
In such a case, a three-dimensional image can be formed with a small amount of clear ink as compared with the case where clear ink is ejected onto all of the color inks. In addition, since the first ultraviolet rays are irradiated to the color ink and the clear ink in a semi-cured state, the adhesion between the two inks is increased, so that an image in which the ink is appropriately cured can be formed.

=== About Modifications ===
In the above, the image forming method for printing an image for preventing forgery or the like has been described in the section of the image printing process for preventing forgery or the like. However, the image forming method is not limited to this, and other examples Is also possible. In this section, two other examples will be described. For convenience of explanation, the image forming method (printing process) described in the section of the image printing process for preventing counterfeiting is the image forming method (printing process) according to the first embodiment. Examples are the image forming methods (printing processes) according to the second embodiment and the third embodiment, respectively.

<<< Print Processing According to Second Embodiment >>>
Here, the printing process (hereinafter referred to as the second printing process) according to the second embodiment is the printing process (hereinafter referred to as the first printing process) according to the above-described first embodiment. Will be described in comparison with (printing process).

  The second printing process includes all the steps of the first printing process, and the second ultraviolet ray is irradiated and the clear ink is ejected onto the color ink (color layer) in a semi-cured state, as shown in FIG. 8D. The process (step S6) is slightly different from the first printing process.

  That is, in the second printing process, similarly to the first printing process, the controller 10 performs the process shown in FIG. 8D in which the second ultraviolet ray is irradiated and the clear ink is ejected onto the semi-cured color ink. However, in such a process, the clear ink ejected toward the semi-cured color ink (that is, the clear ink in a flying droplet state before landing on the color ink) has a lower energy than the first ultraviolet ray. 2 UV rays (the second UV rays are not limited as long as the clear ink is semi-cured during the flight, and need not necessarily be the same as the above-described second UV rays irradiated for semi-curing the color ink. In order to distinguish the second ultraviolet ray from the aforementioned second ultraviolet ray, the clear ink is irradiated by irradiating the ultraviolet ray for flying ink for convenience in the following. Semi-cured during flight. As a result, the semi-cured clear ink is landed on the semi-cured color ink irradiated with the second ultraviolet ray (note that the printer 1 that executes the second printing process has, for example, flying An irradiation unit (not shown) is provided to irradiate the clear ink inside with the flying ink ultraviolet light from the side (specifically, the clear ink flying direction and the flying ink ultraviolet light irradiation direction intersect). Is).

  That is, when the controller 10 ejects the clear ink onto the color ink that has been irradiated with the second ultraviolet rays and is in a semi-cured state, the controller 10 causes the flying clear ink to irradiate the flying ink ultraviolet rays, and the flying ink ultraviolet rays. Is irradiated and the semi-cured clear ink is ejected onto the semi-cured color ink.

  Also in the second embodiment, as in the first embodiment, the concave portion is formed on the surface of the color layer, and the transparent layer constituting the convex portion is also formed, so that forgery and duplication can be prevented by a simple method. There is an effect that an image can be formed. In the second embodiment, unlike the first embodiment, since the semi-cured clear ink is landed on the semi-cured color ink, the uncured clear ink is used as the color ink. Compared with the first embodiment that is landed on the surface, the impact upon landing is increased, and the recess can be formed larger. Further, as compared with the first embodiment in which clear ink that is not semi-cured is landed on the color ink, the clear ink is hard and is not easily crushed, so that the protrusion can be formed larger.

  In the above, in the step shown in FIG. 8D in which the second ultraviolet ray is irradiated and the clear ink is jetted onto the semi-cured color ink, the jetted clear ink is irradiated with the flying ink ultraviolet ray. Although the description has been given of the semi-curing of the clear ink during the flight, the step of ejecting the clear ink onto the clear ink that is irradiated with the first ultraviolet ray and is actually cured (that is, the step of laminating the clear ink. For example, FIG. 8F and the process between FIG. 8G and the process between FIG. 8H and FIG. 8I), the jetted clear ink may be irradiated with the ultraviolet rays for the flying ink so that the clear ink is semi-cured during the flight. In this way, compared to the first embodiment in which clear ink that is not semi-cured is laminated, the laminated clear ink is hard and difficult to be crushed, so that the protrusion can be formed even larger.

  In the first embodiment, the controller 10 can change the magnitude of the energy of the second ultraviolet ray, and adjust the magnitude of the unevenness by changing the magnitude of the energy of the second ultraviolet ray. However, in the second embodiment, the controller 10 can change not only the magnitude of the energy of the second ultraviolet rays but also the magnitude of the energy of the ultraviolet rays for the flying ink. It is possible to adjust the size of the projections and depressions by changing the energy level of the ultraviolet rays for use. Thus, in the second embodiment, it is possible to adjust the size of the finer irregularities than in the first embodiment.

<<< Print Processing According to Third Embodiment >>>
Here, a printing process according to the third embodiment (hereinafter referred to as a third printing process) will be described in comparison with the first printing process and the second printing process described above.

  In the third printing process, the first printing process and the second printing process are performed with respect to the step (step S6) illustrated in FIG. 8D in which the clear ink is ejected onto the color ink (color layer) in a semi-cured state irradiated with the second ultraviolet ray. It is slightly different from the printing process.

  That is, in the third printing process, as in the first printing process and the second printing process, the controller 10 ejects clear ink onto the color ink that is irradiated with the second ultraviolet light and is semi-cured, as shown in FIG. 8D. The first ultraviolet ray (clear ink in a flying state before landing on the color ink) is applied to the first ultraviolet ray (that is, the clear ink in flight before landing on the color ink). The first ultraviolet ray is not limited to the first ultraviolet ray described above as long as it clears the clear ink during the flight, and is not necessarily the same as the first ultraviolet ray described above. For the sake of distinction, the clear ink is irradiated for the sake of convenience (hereinafter referred to as “ultraviolet for flying ink”), and the clear ink is finally cured during the flight. Thus, the fully cured clear ink is landed on the semi-cured color ink irradiated with the second ultraviolet ray (note that the printer 1 executing the third printing process has, for example, flying An irradiation unit (not shown) is provided to irradiate the clear ink inside with the flying ink ultraviolet light from the side (specifically, the clear ink flying direction and the flying ink ultraviolet light irradiation direction intersect). Is).

  That is, when the controller 10 ejects the clear ink onto the color ink that has been irradiated with the second ultraviolet rays and is in a semi-cured state, the controller 10 causes the flying clear ink to irradiate the flying ink ultraviolet rays, and the flying ink ultraviolet rays. The clear ink in the main curing state is ejected onto the color ink in the semi-curing state.

  In the third embodiment as well, as in the first embodiment and the second embodiment, the concave is formed on the surface of the color layer, and the transparent layer constituting the convex is also formed. In addition, it is possible to form an image that can prevent duplication. In the third embodiment, unlike the first embodiment and the second embodiment, the clear ink that has been cured is landed on the color ink in a semi-cured state, and thus the uncured clear ink. Compared with the first embodiment in which the ink is landed on the color ink and the second embodiment in which the semi-cured clear ink is landed on the color ink, the impact upon landing is increased, The recess can be formed larger. Further, the clear ink is compared with the first embodiment in which the uncured clear ink is landed on the color ink and the second embodiment in which the semi-cured clear ink is landed on the color ink. Since it is hard and is not easily crushed, the projection can be formed larger.

  In the third embodiment, since the projections can be formed sufficiently large, unlike the first embodiment and the second embodiment, the step of laminating the clear ink is not performed (that is, the first embodiment shown in FIG. 8F). (1) The process of irradiating ultraviolet rays is performed, but the subsequent processes shown in FIGS. 8G to 8J are not performed).

=== Other Embodiments ===
The fluid ejecting apparatus and the like according to the present invention have been described above based on the above embodiment, but the above-described embodiment is for facilitating the understanding of the present invention and limits the present invention. is not. The present invention can be changed and improved without departing from the gist thereof, and the present invention includes the equivalents thereof.

  In the above-described embodiment, the fluid ejecting apparatus is embodied in an ink jet printer. However, the present invention is not limited to this, and liquids other than ink (in addition to liquids, liquids in which functional material particles are dispersed, such as gels) It is also possible to embody a fluid ejecting apparatus that ejects or discharges a fluid other than a liquid (including a fluid) or a fluid (such as a solid that can be ejected by flowing as a fluid).

  For example, a liquid material injection device for injecting a liquid material in the form of dispersed or dissolved materials such as electrode materials and color materials used in the manufacture of liquid crystal displays, EL (electroluminescence) displays, and surface-emitting displays, and biochip manufacturing It may be a liquid ejecting apparatus for ejecting a bio-organic substance used in the above, or a liquid ejecting apparatus for ejecting a liquid as a sample used as a precision pipette. In addition, transparent resin liquids such as UV curable resins to form liquid injection devices that inject lubricating oil onto precision machines such as watches and cameras, and micro hemispherical lenses (optical lenses) used in optical communication elements. For example, a liquid ejecting apparatus that ejects a liquid onto a substrate, a liquid ejecting apparatus that ejects an etching solution such as acid or alkali to etch the substrate, a fluid ejecting apparatus that ejects gel, and a powder such as toner It may be a powder jet recording apparatus that jets a solid. The present invention can be applied to any one of these injection devices.

  Moreover, in the said embodiment, although the irradiation part 52 decided to be a metal halide lamp, it is not limited to this. For example, the irradiation unit 52 may be an LED.

  Further, the ink ejection method is not limited to that using a piezo element, and can be applied to, for example, a thermal printer.

  In the above embodiment, the ink is ejected onto the paper S that is wound around and held by the rotating holding drum 31. However, the present invention is not limited to this. For example, the ink may be ejected onto a sheet S supported by a fixed support member (so-called platen) (this sheet S is conveyed by a conveyance roller or the like).

1 printer, 10 controller, 11 interface, 12 CPU,
13 memory, 14 unit control circuit, 15 timer,
20 paper feed / discharge unit, 21 paper feed unit, 22 paper discharge unit,
30 drum unit, 31 holding drum, 32 rotating shaft, 33 outer peripheral surface,
40 head unit, 41 head carriage, 42a to 42e head,
43a-43e storage chamber, 44a-44e nozzle plate,
46 guide shaft, 47 guide shaft,
50 UV irradiation unit, 51 irradiation unit carriage, 52 irradiation unit,
53 lamp, 56 guide shaft, 57 guide shaft,
60 ink supply unit, 61a to 61e ink cartridge,
70 detector groups, 110 computers

Claims (6)

An ejection unit that ejects a colored fluid and a colorless fluid onto a medium;
An irradiating unit for irradiating the fluid on the medium with ultraviolet rays, the irradiating unit for irradiating the first ultraviolet rays for curing the fluid and the second ultraviolet rays having energy smaller than the first ultraviolet rays;
A control unit for controlling a fluid ejection operation by the ejection unit and an ultraviolet irradiation operation by the irradiation unit;
After spraying the colored fluid onto the medium, the colored fluid is irradiated with the second ultraviolet light,
A controller that irradiates the colorless fluid with the colorless fluid after the colorless fluid is ejected onto the colored fluid that is irradiated with the second ultraviolet light and is semi-cured; and
A fluid ejecting apparatus comprising: The fluid ejection device according to claim 1,
The control unit causes the colorless fluid to be ejected a plurality of times on the colored fluid that has been irradiated with the second ultraviolet rays and is in a semi-cured state, thereby laminating the colorless fluid. . The fluid ejecting apparatus according to claim 2,
The control unit alternately repeats the ejection of the colorless fluid onto the colored fluid that is irradiated with the second ultraviolet rays and is semi-cured and the irradiation of the first ultraviolet rays to the colorless fluid. The fluid ejecting apparatus, wherein the colorless fluid is laminated on the colored fluid. The fluid ejection device according to any one of claims 1 to 3,
The controller is
Irradiation of the colorless fluid onto the colored fluid in a semi-cured state irradiated with the second ultraviolet rays, and then irradiating the colorless fluid with the first ultraviolet rays, thereby forming an uneven image. And
The magnitude of the energy of the second ultraviolet light can be changed,
The fluid ejecting apparatus, wherein the size of the unevenness is adjusted by changing the magnitude of the energy of the second ultraviolet ray. The fluid ejection device according to any one of claims 1 to 4,
The control unit ejects the colorless fluid onto a part of the colored fluid that is irradiated with the second ultraviolet rays and is in a semi-cured state, and then the first fluid is applied to the colorless fluid and the colored fluid. A fluid ejecting apparatus characterized by irradiating ultraviolet rays. Injecting a colored fluid onto the medium;
Irradiating the colored fluid on the medium with a second ultraviolet ray having lower energy than the first ultraviolet ray for curing the fluid;
Spraying a colorless fluid on the colored fluid that has been irradiated with the second ultraviolet rays and is in a semi-cured state;
Irradiating the colorless fluid on the colored fluid with the first ultraviolet light;
An image forming method comprising:

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