Printing apparatus and method

Abstract

The present application provides a printing device and method that can enrich the expression of the glossiness of a printed image and make it more realistic. The printing device has a gloss forming section that forms at least two regions with different glossiness on a printing medium, and a printed image forming section that forms a printed image on the above regions on the printing medium after the at least two regions with different glossiness are formed by the gloss forming section.

Description

Technical Field

[0001] This invention relates to a printing apparatus and method for forming a glossy printed image on a printing medium. Background Technology

[0002] In recent years, the operation of forming printed images on printing media made of various materials has become possible, not just limited to prescribed patterns, but also enabling the representation of any image desired by the user on various printing media.

[0003] There has always been a process of applying gloss to printed images, typically by applying a gloss liquid, such as a transparent ink, after the printed image has been formed.

[0004] For example, Patent Document 1 and Patent Document 2 propose a technique for imparting gloss to a printing medium on which a printed image is formed using transparent ink.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2019-217760

[0008] Patent Document 2: Japanese Patent Application Publication No. 2017-043004 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] However, in Patent Document 1 and Patent Document 2, since a transparent ink is uniformly applied to a printing medium, although the gloss can be adjusted, the overall gloss of the printing medium is uniformly adjusted.

[0011] There are cases where the glossy part, such as glass or metal, is only contained in a portion of an object, or where only the illuminated areas of the object are intended to have a glossy appearance. In these cases, if the printing medium is made to have a uniform gloss throughout, as in Patent Documents 1 and 2, the glossiness of the object cannot be realistically represented.

[0012] The purpose of this invention is to provide a printing apparatus and method that can enrich the glossiness of printed images and make them more realistic.

[0013] means for solving problems

[0014] The printing apparatus of the present invention comprises: a gloss forming section that forms at least two regions with different gloss levels on a printing medium; and a printing image forming section that forms a printing image on the aforementioned regions on the printing medium after the gloss forming section has formed the at least two regions with different gloss levels.

[0015] Invention Effects

[0016] According to the printing apparatus of the present invention, since it is configured to form at least two regions with different gloss levels, and the printed image is formed after the regions are formed, the gloss level of the printed image can be enriched, the color tone of the printed matter will not deviate, and a printed matter with a desired gloss level that makes it more realistic can be obtained. Attached Figure Description

[0017] Figure 1 This is a block diagram illustrating the general structure of an inkjet printing apparatus using one embodiment of the printing apparatus of the present invention.

[0018] Figure 2 This is a diagram showing an example of image data representing a printed image.

[0019] Figure 3 This is a graph showing an example of a function representing the relationship between brightness and gloss.

[0020] Figure 4 This is another example of a function that represents the relationship between brightness and gloss.

[0021] Figure 5 This is an example diagram of a table that shows the gloss level corresponding to the grayscale value of the brightness.

[0022] Figure 6 This is a diagram showing an example of a table that sets gloss levels relative to ten brightness levels.

[0023] Figure 7 This is a diagram showing an example of a table that sets the gloss level relative to all colors.

[0024] Figure 8 This is an example of a table showing the gloss levels corresponding to all combinations of R, G, and B values.

[0025] Figure 9 These are other examples of how to set areas with different gloss levels.

[0026] Figure 10 It is a perspective view showing the outline structure of the main body of the inkjet printing device.

[0027] Figure 11 This is a diagram showing the internal structure of the shuttle unit.

[0028] Figure 12 It is used for Figure 10 The diagram illustrates the operation of the inkjet printing device.

[0029] Figure 13 This is a diagram illustrating an example of how the dots of a gloss liquid are arranged.

[0030] Figure 14 This is another example of a method for configuring dots in a glossy liquid.

[0031] Explanation of reference numerals in the attached figures:

[0032] 1: Inkjet printing equipment;

[0033] 2: Shuttle-type base unit;

[0034] 3: Flat base unit;

[0035] 3a: Medium mounting surface;

[0036] 4: Shuttle unit;

[0037] 6: Gloss liquid coating unit;

[0038] 10: Printing control device;

[0039] 11: Printed Image Data Generation Department;

[0040] 12: Gloss data generation unit;

[0041] 13: Control Department;

[0042] 20: Main body of the inkjet printing device;

[0043] 31: Standing department;

[0044] 32: Sub-scan drive motor;

[0045] 41: Shell;

[0046] 42: Main scan driver bootloader;

[0047] 43: Main scanning drive motor;

[0048] 44: Head lifting guide;

[0049] 45: Head lifting motor;

[0050] 46: Head unit;

[0051] 51: Inkjet head;

[0052] 53: Ink supply pipe;

[0053] 33A, 33B: Sub-scan driver bootloader. Detailed Implementation

[0054] Hereinafter, an inkjet printing apparatus using one embodiment of the printing apparatus of the present invention will be described in detail with reference to the accompanying drawings. Figure 1 This is a block diagram showing the general structure of the inkjet printing apparatus 1 according to this embodiment.

[0055] like Figure 1 As shown, the inkjet printing apparatus 1 of this embodiment includes a printing control device 10 and an inkjet printing apparatus main body 20.

[0056] The printing control device 10 and the inkjet printing apparatus main body 20 are configured to communicate with each other via a wired or wireless connection such as a LAN (Local Area Network). Alternatively, the printing control device 10 and the inkjet printing apparatus main body 20 can be connected via an Internet line.

[0057] The printing control device 10 outputs various control information related to the printing process to the main body 20 of the inkjet printing device. For example... Figure 1 As shown, the printing control device 10 includes a printing image data generation unit 11, a gloss data generation unit 12, and a control unit 13.

[0058] The printing control device 10 is composed of a computer equipped with a CPU (Central Processing Unit), semiconductor memory, and hard disk. The printing control device 10 executes a control program pre-stored in a storage medium such as semiconductor memory or hard disk, and controls the circuitry by activating it. Figure 1 The parts shown.

[0059] The printing image data generation unit 11 generates printing image data for forming a printing image based on the input image data of the printing object. Specifically, the printing image data generation unit 11 generates printing image data of C (cyan), M (magenta), Y (yellow), and K (black) based on the image data representing the printing image.

[0060] The gloss data generation unit 12 generates gloss data based on image data representing a printed image. Gloss data refers to data used to control the amount of gloss liquid applied based on the gloss liquid coating unit 6 described later. In this embodiment, gloss data is generated such that at least two areas with different gloss levels are formed on the printing medium. The method for generating gloss data will be described in detail later.

[0061] In the inkjet printing apparatus 1 of this embodiment, since it is configured to form at least two regions with different gloss levels for the printed image, the gloss level of the printed image can be enriched, making it more realistic.

[0062] Furthermore, since the inkjet printing apparatus 1 of this embodiment is configured to generate gloss data based on image data representing the printed image, it is possible to impart gloss corresponding to the content of the printed image.

[0063] The control unit 13 generates an ink ejection control signal based on the printed image data of C, M, Y, and K, and outputs the generated ink ejection control signal to the main body 20 of the inkjet printing apparatus. In addition, the control unit 13 generates a gloss liquid ejection control signal based on gloss data, and outputs the gloss liquid ejection control signal to the main body 20 of the inkjet printing apparatus.

[0064] The inkjet printing apparatus main body 20 discharges gloss liquid onto the printing medium based on a gloss liquid discharge control signal output from the control unit 13, and then discharges ink onto the printing medium based on an ink discharge control signal to form a printed image. The structure of the inkjet printing apparatus main body 20 will be described in detail later.

[0065] Next, the method for generating gloss data based on the gloss data generation unit 12 will be explained. First, the method for generating gloss data based on the brightness of image data representing a printed image will be explained.

[0066] Image data representing a printed image, for example, monochrome data, has... Figure 2 In the case of regions a, b, and c with different brightness levels as shown, the brightness of each region a through c is calculated using the image data of regions a, b, and c. When the image data is monochrome, the brightness value of each pixel is applied.

[0067] The gloss data generation unit 12 is pre-set with, for example, Figure 3 The function representing the relationship between brightness and gloss is shown. The gloss data generation unit 12 generates data based on the brightness La of region a, the brightness Lb of region b, and the brightness Lc of region c. Figure 3 The gloss GLa, GLb, and GLc corresponding to the brightness La, Lb, and Lc of each region are obtained using the functions shown.

[0068] Then, the gloss data generation unit 12 generates gloss data such that the amount of gloss liquid corresponding to gloss GLa is applied to region a, the amount of gloss liquid corresponding to gloss GLb is applied to region b, and the amount of gloss liquid corresponding to gloss GLc is applied to region c.

[0069] As described above, when the gloss data is generated based on the brightness of the image data representing the printed image, gloss can be imparted in accordance with the brightness of the printed image. Furthermore, by forming the printed image after applying the gloss liquid, as described later, the effect of the gloss liquid's turbidity on the printed image can be suppressed.

[0070] In addition, when the image data representing the printed image is color data, the brightness La to Lc of each region a to c is calculated based on the following formula (1).

[0071] L=(R×kr)+(G×kg)+(B×kb) ··· (1)

[0072] Where R is the R value, G is the G value, and B is the B value. Then, the R value refers to the grayscale value of red, the G value refers to the grayscale value of green, and the B value refers to the grayscale value of blue. Additionally, kr, kg, and kb are pre-defined coefficients.

[0073] The coefficients kr, kg, and kb can be set, for example, kr = 0.3, kg = 0.6, and kb = 0.1. However, the coefficients kr, kg, and kb are not limited to these values, and are preferably within the range of the following formula (2).

[0074] 0.15 ≤ coefficient kr ≤ 0.35

[0075] 0.55 ≤ coefficient kg ≤ 0.75

[0076] 0 ≤ coefficient kb ≤ 0.2 ··· (2)

[0077] Table 1 below is a table that uses text to represent the R value, G value, B value, and luminance L corresponding to each region a to c. Table 2 below is a table that represents the specific R value, G value, and B value corresponding to each region a to c, and the specific luminance L value calculated based on the R value, G value, and B value and the above formula (1). It should be noted that each region a to c is set to monochrome.

[0078] [Table 1]

[0079] area R value G value B value Brightness (L) a Ra Ga Ba La b Rb Gb Bb Lb c Rc Gc Bc Lc

[0080] [Table 2]

[0081] area R value G value B value Brightness (L) a 255 0 255 102 b 0 255 255 179 c 255 255 0 230

[0082] Then, similarly to the case of monochrome data, the glossiness data generation unit 12 pairs... Figure 3 The function shown takes the brightness La of region a, the brightness Lb of region b, and the brightness Lc of region c as input, and then calculates the gloss GLa, GLb, and GLc corresponding to the brightness La, Lb, and Lc of each region a to c.

[0083] As described above, the brightness is calculated based on the above formula (1), and gloss data is generated based on the brightness, so that even when the printed image is in color, a gloss corresponding to the brightness can be given.

[0084] Furthermore, by setting the coefficients kr, kg, and kb of equation (1) to the range of equation (2), a more appropriate brightness can be calculated.

[0085] Furthermore, since the gloss liquid is not completely colorless but has color, it is possible to suppress the influence of the gloss liquid's color on the printed image by forming a printed image after applying the gloss liquid, as described later.

[0086] It should be noted that the function representing the relationship between luminance L and gloss GL is not limited to... Figure 3 The function shown. Figure 3 The function shown represents high gloss for bright areas and low gloss for dark areas in a printed image, but it can also be used as follows: Figure 4 As shown in A, conversely, the darker parts of the printed image are represented as high gloss, and the lighter parts as low gloss.

[0087] In addition, it is not necessary. Figure 3 as well as Figure 4 A linear function as shown in Figure A can be as follows: Figure 4 The functions shown in B to D are quadratic functions and other functions.

[0088] Alternatively, multiple functions representing the relationship between brightness L and gloss GL can be pre-defined, allowing the user to select the desired function based on the content of the printed image.

[0089] Alternatively, the function can be set differently than described above, such as... Figure 5 As shown, a table is used to set gloss levels GL000 to GL255 corresponding to grayscale values ​​L ranging from 0 to 255.

[0090] Furthermore, in the above description, the goal is to calculate the gloss level corresponding to the grayscale value L of 0 to 255, but this is not a limitation. For example, it could be as follows: Figure 6 As shown, the grayscale value L of brightness from 0 to 255 is divided into ten levels from 0 to 9, and gloss levels GL0 to GL9 are set for each level corresponding to each zone. Then, it is also possible to determine which zone the brightness La, Lb, and Lc of each region a, b, and c belong to, and set the gloss level corresponding to the determined zone as the gloss level GLa, GLb, and GLc of each region a, b, and c.

[0091] Additionally, when the image data representing a printed image is color data, it can also be like this: Figure 7 As shown in A, the entire color gamut is represented by regions based on wavelength and chromaticity, which are then divided into 10×10=100 smaller areas, as shown in Figure A. Figure 7 As shown in B, the gloss level is preset to correspond to each small area. This allows each pixel representing the image data of the printed image to reflect the gloss level set in the small area containing that pixel's color. It should be noted that in... Figure 7In section A, the entire color gamut is represented by regions along wavelength and chromaticity axes. However, it can also be represented by regions along chromaticity values ​​such as Lab, or by regions along chromaticity and luminance axes. Thus, when gloss data is generated based on the hue (wavelength and chromaticity) of the image data, the desired gloss can be assigned to each color. Furthermore, since the gloss liquid is not completely colorless but has color, as described later, by forming a printed image after applying the gloss liquid, the influence of the wavelength characteristics (hue) of the gloss liquid on the printed image can be suppressed.

[0092] Alternatively, it can be displayed. Figure 7 In the attached diagram (x: wavelength, y: chromaticity), like A, the user selects the color they want to impart a sheen from various color sub-divisions, referring to... Figure 7 The gloss values ​​are obtained from the table shown in B, thus generating gloss data.

[0093] Alternatively, it can be like Figure 8 The table shown pre-sets a gloss level GL000000000 to GL255255255 corresponding to all combinations of R values ​​(0-255), G values ​​(0-255), and B values ​​(0-255). Alternatively, the gloss level data generation unit 12 can be configured to generate data based on combinations of R, G, and B values ​​for each region a-c and refer to... Figure 8 The table is used to determine the gloss level corresponding to the combination of R, G, and B values ​​for each region a to c, thereby calculating the gloss level of each region a to c.

[0094] When gloss data is generated based on the grayscale values ​​of image data as described above, gloss can be imparted with more precise color gradations, resulting in a richer gloss representation. Furthermore, since the gloss liquid is not completely colorless but has colors equivalent to grayscale values, as explained later, the influence of colors equivalent to the grayscale values ​​of the gloss liquid on the printed image can be suppressed by forming a printed image after applying the gloss liquid.

[0095] Furthermore, in the above description, an example of gloss data generation unit 12 generating gloss data based on image data representing a printed image was described, but the method of generating gloss data is not limited to this.

[0096] For example, for each region a to c, the system can receive user-defined settings based on the incident angle θ and the desired gloss level at that angle θ, and generate gloss data that determines the amount of gloss liquid to be applied to each region a to c from the incident angle θ and the desired gloss level. It should be noted that the relationship between the incident angle θ, the desired gloss level, and the amount of gloss liquid applied is preset using functions, tables, etc.

[0097] By receiving information about the angle of incidence and gloss as described above, and generating gloss data based on the information about the angle of incidence and gloss, the user can be given the desired gloss.

[0098] In addition, since the gloss liquid has a thickness, it is easy to have uneven gloss due to halos, etc. However, the effect of the thickness of the gloss liquid on the printed image can be suppressed by forming a printed image after applying the gloss liquid, as described later.

[0099] It should be noted that in the above explanation, when using functions and tables to calculate gloss, the functions and tables are preset with an incident angle of 60 degrees. However, this is not the only limitation; functions and tables can also be set for each of multiple incident angles. This allows for obtaining a more desirable gloss level.

[0100] Furthermore, in the above description, it is set that different gloss levels are set for region a of the circular image, region b of the triangular image, and region c of the quadrilateral image. However, there are various methods for setting regions with different gloss levels.

[0101] For example, it can be like Figure 9 The example shows how to set the gloss level and apply gloss liquid only to a portion of a circular image (e), or only to a portion of a triangular image (f). That is, it's also possible to set different gloss levels and apply gloss liquid to a portion of a uniform image (e.g., an image of an apple or a clock) compared to other areas. Alternatively, it can be done as follows... Figure 9 The area shown in the frame image is divided into multiple segments g1 to g21 within a neat image. Each segment is assigned a different gloss level and coated with a gloss liquid. Alternatively, two areas with different gloss levels can be created by setting an area with a set gloss level and an area without a set gloss level or with a set gloss level of 0 within a single printing medium.

[0102] Next, for Figure 1 The main body 20 of the inkjet printing device shown will be described. Figure 10 This is a perspective view showing the outline structure of the main body 20 of the inkjet printing apparatus. In the following description of the embodiment, ... Figure 10 The arrows in the middle indicate the directions of up, down, left, right, front, and back of the inkjet printing device body 20.

[0103] like Figure 10As shown, the main body 20 of the inkjet printing apparatus includes a shuttle base unit 2, a flat base unit 3, a shuttle unit 4, and a gloss liquid coating unit 6. It should be noted that, in this embodiment, the shuttle unit 4, the printed image data generation unit 11, and the control unit 13 correspond to the printed image forming unit of the present invention, and the gloss liquid coating unit 6, the gloss data generation unit 12, and the control unit 13 correspond to the gloss forming unit of the present invention.

[0104] The shuttle base unit 2 supports the shuttle unit 4 and the gloss liquid coating unit 6, and moves the shuttle unit 4 and the gloss liquid coating unit 6 in the front-back direction (sub-scanning direction). Specifically, the shuttle base unit 2 includes a platform portion 31, sub-scanning drive guides 33A and 33B, and a sub-scanning drive motor 32 (see reference). Figure 1 ).

[0105] The frame portion 31 is formed in the shape of a rectangular frame, supporting the shuttle unit 4 and the gloss liquid coating unit 6. Sub-scanning drive guides 33A and 33B, extending in the front-to-back direction, are formed on the left and right sides of the frame portion 31, respectively. The sub-scanning drive guides 33A and 33B guide the shuttle unit 4 and the gloss liquid coating unit 6 to move them in the front-to-back direction. The sub-scanning drive motor 32 moves the shuttle unit 4 and the gloss liquid coating unit 6 in the front-to-back direction.

[0106] The flat base unit 3 supports the printing medium M. The flat base unit 3 is disposed within a cuboid-shaped recess formed inside the frame portion 31 of the shuttle-type base unit 2. The flat base unit 3 has a media mounting surface 3a that serves as a horizontal plane for placing the printing medium M. The flat base unit 3 includes a hydraulic drive mechanism (not shown), thereby enabling adjustment of the height of the media mounting surface 3a.

[0107] Shuttle unit 4 is a component that performs printing image forming processing on printing medium M. Figure 11 This is a diagram showing the outline structure of shuttle unit 4.

[0108] like Figure 11 As shown, the shuttle unit 4 includes a housing 41, a main scan drive guide 42, and a main scan drive motor 43 (see reference). Figure 1 ), head lifting guide 44, head lifting motor 45 (refer to) Figure 1 ), and head unit 46.

[0109] The housing 41 houses the various parts of the head unit 46, etc. The housing 41 is formed as a door shape that spans the flat base unit 3 in the left-right direction. The housing 41 is configured to be supported by the frame portion 31 of the shuttle base unit 2 and can move along the sub-scan drive guides 33A and 33B.

[0110] The main scan drive guide 42 guides the head unit 46 to move in the left-right direction (main scan direction). The main scan drive guide 42 is formed of an elongated strip-shaped component extending in the left-right direction. The head unit 46 moves in the left-right direction via the main scan drive motor 43.

[0111] The head lifting guide 44 guides the head unit 46 to move it in the vertical direction. The head lifting guide 44 is formed of a member with an elongated shape in the vertical direction. The head lifting guide 44 is configured to move in the left-right direction along the main scan drive guide 42 together with the head unit 46. The head unit 46 is raised and lowered in the vertical direction by the head lifting motor 45.

[0112] The head unit 46 moves in the left-right direction along the main scan drive guide 42 as described above, while performing a printing image formation process by discharging ink into the printing medium M. Figure 11 As shown, the head unit 46 has four inkjet heads 51.

[0113] Four inkjet heads 51 are arranged side by side in a left-right direction. The four inkjet heads 51 respectively discharge ink of type C, M, Y and K. Ink supply tubes 53 for supplying ink to each ink are connected to the four inkjet heads 51.

[0114] Back Figure 10 The gloss coating unit 6 applies gloss coating to the printing medium M to perform gloss coating treatment. It should be noted that known materials can be used as the gloss coating.

[0115] The gloss liquid application unit 6 is configured to be supported by the frame portion 31 of the shuttle base unit 2 and is movable along the sub-scanning drive guides 33A and 33B. The gloss liquid application unit 6 applies gloss liquid to a predetermined area on the printing medium M below it by moving in the sub-scanning direction.

[0116] The gloss liquid coating unit 6 has the same structure as the shuttle unit 4. While moving the inkjet head in the left-right direction (main scanning direction), it discharges gloss liquid from the inkjet head to perform gloss liquid coating treatment.

[0117] The inkjet printing apparatus body 20 corresponds to the control signal from the printing control device 10, causing... Figure 1 The actions of each part of the controlled object are shown.

[0118] Next, refer to Figure 12 The operation of the inkjet printing apparatus 1 according to this embodiment is explained by A to D. It should be noted that... Figure 12 A through D in the diagram are viewed from the left side. Figure 10 The figure shows the main body 20 of the inkjet printing device.

[0119] First, such as Figure 12As shown in Figure A, the printing medium M is placed on the flat base unit 3. At this time, as... Figure 12 As shown in Figure A, the shuttle unit 4 and the gloss liquid coating unit 6 are positioned at the foremost initial position. Then, the printing control device 10 drives the sub-scanning drive motor 32, thereby causing the shuttle unit 4 and the gloss liquid coating unit 6 to begin scanning from... Figure 12 The initial position A in the diagram is in the backward direction ( Figure 12 Move (in the direction of the arrow A shown in the image) to the point where... Figure 12 The printing start position is indicated by B in the diagram.

[0120] Next, as Figure 12 As shown in C, the printing control device 10 moves the gloss liquid coating unit 6 in the forward direction ( Figure 12 The inkjet head in the gloss coating unit 6 moves (in the direction of arrow C) and applies gloss liquid to the printing medium M to perform gloss liquid coating treatment.

[0121] Specifically, firstly, with the gloss liquid coating unit 6 positioned at the printing start position, the printing control device 10 controls the main scanning drive motor 43 to move the inkjet head discharging the gloss liquid along the main scanning direction. Then, the inkjet head discharges the gloss liquid in response to the gloss liquid discharge control signal based on gloss data, thereby performing one pass of gloss liquid coating process.

[0122] After one pass of gloss liquid application is completed, the printing control device 10 controls the sub-scan drive motor 32 to move the gloss liquid application unit 6 forward to the next printing position. By alternately repeating the gloss liquid application process and the movement of the gloss liquid application unit 6, the printing control device 10 applies gloss liquid to a predetermined area within the printing medium M.

[0123] Then, after the gloss liquid is applied to the printing medium M through the gloss liquid coating unit 6, the printing medium M is temporarily transferred to a drying device (not shown) for drying. After the drying process in the drying device is completed, the printing medium M is placed back on the inkjet printing unit body 20, and the printing control device 10 controls the sub-scan drive motor 32 as follows... Figure 12 As shown in D, one side causes shuttle unit 4 to move forward ( Figure 12 Move one side (in the direction of arrow D in the diagram) for printing.

[0124] Specifically, the printing control device 10 first controls the main scanning drive motor 43 to move the head unit 46 along the main scanning direction when the shuttle unit 4 is positioned at the printing start position. Then, the inkjet head 51 of the head unit 46 ejects ink in response to the ink ejection control signal based on the printed image, thereby performing one printing pass.

[0125] After one printing pass is completed, the printing control device 10 controls the sub-scan drive motor 32 to move the shuttle unit 4 forward to the next printing position. By alternately repeating the printing process of one pass and the movement of the shuttle unit 4, the printing control device 10 forms a printed image on the printing medium M.

[0126] Then, at the end of the printing process for one sheet, the shuttle unit 4 and the gloss liquid coating unit 6, as... Figure 12 The state shown by D in the diagram is the state of being reconfigured to the initial position.

[0127] As described above, by forming at least two areas with different gloss levels in a single scan, it is possible to obtain printed materials with the desired gloss level in a shorter processing time.

[0128] Furthermore, in this embodiment, as described above, the gloss liquid is applied to the printing medium M by the gloss liquid application unit 6, and then the printed image is formed by the shuttle unit 4. If, as in the past, the gloss liquid such as transparent ink is applied after the printed image is formed, there is a concern that the transparency of the gloss liquid will increase the color of the printed image, resulting in a cloudy color and the final printed product deviating from the desired tone.

[0129] However, as in this embodiment, the printed image is formed after the gloss liquid is applied, so that the color tone of the printed matter will not be deviated, and a printed matter with the desired gloss level can be obtained.

[0130] It should be noted that in the inkjet printing apparatus 1 of the above embodiment, the drying device is configured in a different way. However, like the gloss liquid coating unit 6, the drying unit can also be provided in the main body 20 of the inkjet printing apparatus, and the drying process is performed by scanning the printing medium M through the drying unit.

[0131] In this embodiment, a gloss liquid coating unit 6 is provided in the main body 20 of the inkjet printing apparatus. However, it is not limited to the structure described above. For example, an inkjet printing apparatus equipped with a shuttle unit 4 and a gloss liquid coating apparatus equipped with a gloss liquid coating unit 6 may be provided separately. Then, the printing medium M, which has undergone gloss liquid coating treatment in the gloss liquid coating apparatus, may be moved to the inkjet printing apparatus, and printing treatment may be performed on the printing medium M that has undergone gloss liquid coating treatment.

[0132] Furthermore, in the description of the above embodiment, the gloss liquid is applied to the area to which the gloss liquid is to be applied by a single scan (single coating process) based on the inkjet head of the gloss liquid coating unit 6. However, it is not limited to this and the gloss liquid can also be applied by multiple scans.

[0133] Alternatively, in the case of applying the gloss liquid through multiple scans, the gloss liquid coating unit 6 forms an area with a predetermined gloss level by forming a new point on top of the points already formed within the unit area after forming a predetermined maximum number of points without overlap within a predetermined unit area. Hereinafter, refer to... Figure 13 The method for forming regions with a predetermined gloss level is explained in sections A through H.

[0134] exist Figure 13 In sections A through H, examples are shown of points formed by a liquid gloss liquid in an area consisting of four boxes (unit area) with a predetermined gloss level. The maximum number of points formed in each box is four. White circles indicate points formed by a single discharge, and black circles indicate points formed by two discharges to the same location. The gloss level is determined according to the desired gloss level. Figure 13 The points are formed in the order of A to H. That is, Figure 13 In the diagram, A to H represent the configuration method of points to obtain gloss levels of eight color gradations.

[0135] First, given a gloss level of one color gradation, such as Figure 13 As shown in A, the first point is formed in each box. Next, with two levels of glossiness obtained, as... Figure 13 As shown in B, a second point is formed in each box. Then, with three levels of glossiness obtained, as... Figure 13 As shown in C, a third point is formed in each box, achieving four levels of glossiness, as shown in the image. Figure 13 As shown by D in the diagram, a fourth point is formed within each box. (See diagram below.) Figure 13 As shown in A to D, the dots are formed in a non-overlapping manner up to the gloss level of four color levels, that is, up to the maximum number of four dots that can be formed within a box.

[0136] Next, after filling each frame with the maximum number of (four) points, as follows: Figure 13 As shown in E~H, through with Figure 13 The points A through D in the diagram are arranged using the same method, overlapping existing points to form new points.

[0137] Specifically, such as Figure 13 As shown in E, within each box, in Figure 13 The points formed in A overlap to form a fifth point, resulting in five levels of glossiness. Next, as... Figure 13 As shown in F, within each box, in Figure 13 The sixth point is formed by overlapping the points created in B, resulting in six levels of glossiness. Then, as... Figure 13 As shown in G, within each box, in Figure 13The points formed in C overlap to form a seventh point, thus obtaining seven levels of glossiness. Then, as... Figure 13 As shown by H in the diagram, within each box, in Figure 13 The points formed in D overlap to form the eighth point, thus obtaining eight levels of glossiness.

[0138] It should be noted that the gloss level can be further increased by controlling the amount of gloss liquid used to form a single spot when forming the spot as described above. As a method for controlling the amount of gloss liquid, a so-called multi-spot method can be used, for example, by dispensing multiple drops of gloss liquid to form a single spot.

[0139] It should be noted that the method for obtaining gloss levels in eight color levels is the same as described above, but the reference is... Figure 14 The different methods for configuring points A through H in the diagram will be explained.

[0140] First, given a gloss level of one color gradation, such as Figure 14 As shown in A, the first point is formed in each box. Next, with two levels of glossiness obtained, as... Figure 14 As shown in B, in Figure 14 The second point is formed by overlapping the first point that has already been formed in A.

[0141] Next, after obtaining three levels of gloss, such as Figure 14 As shown in C, a third point is formed in each box, achieving four levels of glossiness, as shown in the image. Figure 14 As shown in D, in Figure 14 The fourth point is formed by overlapping the third point that has already been formed in point C.

[0142] Next, having obtained five levels of glossiness, such as Figure 14 As shown in E, a fifth point is formed in each box, achieving six levels of glossiness, as shown in... Figure 14 As shown in F, in Figure 14 The sixth point is formed by overlapping the fifth point that has already been formed in point E.

[0143] Then, having achieved seven levels of glossiness, such as Figure 14 As shown in G, a seventh point is formed in each box, achieving eight levels of glossiness, as shown in the image. Figure 14 As shown by H in the figure, in Figure 14 The G in the middle has overlapped with the seventh point to form the eighth point.

[0144] In such Figure 14In the case where points A to G are provided with gloss liquid, that is, when points are formed by overlapping existing points before filling each frame with the maximum number of points, the gloss is hindered because the substrate of the points without gloss liquid is exposed, making it difficult to obtain the desired gloss.

[0145] In this regard, such as Figure 13 As shown in A to G, since the dots of gloss liquid are arranged in a way that minimizes exposure of the substrate, the gloss gradation can be made smooth, and the desired gloss level can be obtained.

[0146] The following notes are also disclosed regarding this invention.

[0147] (Postscript 1)

[0148] The printing apparatus of the present invention comprises: a gloss forming section that forms at least two regions with different gloss levels on a printing medium; and a printing image forming section that forms a printing image on a region of the printing medium after the gloss forming section has formed the at least two regions with different gloss levels.

[0149] (Postscript 2)

[0150] Based on the printing apparatus described in Appendix 1, the gloss forming unit is able to generate gloss data based on image data representing a printed image, and use the gloss data to form at least two regions with different gloss levels.

[0151] (Note 3)

[0152] Based on the printing apparatus described in Appendix 2, the gloss forming unit is able to generate gloss data based on the brightness of the image data.

[0153] (Note 4)

[0154] Based on the printing apparatus described in Appendix 3, the gloss forming unit can calculate the brightness of each pixel based on the following formula and the red, green, and blue gray values ​​of each pixel constituting the image data.

[0155] Brightness = Coefficient kr × Red gray value + Coefficient kg × Green gray value + Coefficient kb × Blue gray value.

[0156] (Note 5)

[0157] Based on the printing apparatus described in Appendix 4, the coefficients kr, kg, and kb are within the range that can satisfy the following formula.

[0158] 0.15 ≤ coefficient kr ≤ 0.35

[0159] 0.55 ≤ coefficient kg ≤ 0.75

[0160] 0 ≤ coefficient kb ≤ 0.2

[0161] (Note 6)

[0162] Based on the printing apparatus described in Appendix 2, the gloss forming unit is able to generate gloss data based on the hue of the image data.

[0163] (Note 7)

[0164] Based on the printing apparatus described in Appendix 2, the gloss forming unit is able to generate gloss data based on the grayscale values ​​of the image data.

[0165] (Postscript 8)

[0166] Based on the printing apparatus described in Appendix 2, the gloss forming unit is able to receive information about the angle of incidence and gloss information, and generate gloss data based on the information about the angle of incidence and gloss information.

[0167] (Note 9)

[0168] Based on the printing apparatus described in any of Appendix 1 to Appendix 8, the gloss forming section is capable of forming at least two areas with different gloss levels in a single coating process.

[0169] (Postscript 10)

[0170] Based on the printing apparatus described in any of Appendix 1 to Appendix 9, the gloss forming unit applies gloss liquid by forming dots within a predetermined unit area and is able to form a predetermined maximum number of dots without overlap within the unit area, and then forms new dots on the dots already formed within the unit area.

[0171] (Postscript 11)

[0172] Based on the printing method of the present invention, after forming at least two regions with different gloss on the printing medium, a printed image is formed in the regions.

[0173] (Postscript 12)

[0174] Based on the printing method described in Appendix 11, it is possible to generate gloss data based on image data representing a printed image, and to use the gloss data to form at least two regions with different gloss levels.

[0175] (Postscript 13)

[0176] Based on the printing method described in Appendix 12, gloss data can be generated based on the brightness of the image data.

[0177] (Postscript 14)

[0178] Based on the printing method described in Appendix 13, the brightness of each pixel can be calculated based on the following formula and the red, green, and blue gray values ​​of each pixel constituting the image data.

[0179] Brightness = Coefficient kr × Red gray value + Coefficient kg × Green gray value + Coefficient kb × Blue gray value.

[0180] (Postscript 15)

[0181] Based on the printing method described in Appendix 14, the coefficients kr, kg, and kb are set to satisfy the following formula:

[0182] 0.15 ≤ coefficient kr ≤ 0.35

[0183] 0.55 ≤ coefficient kg ≤ 0.75

[0184] 0 ≤ coefficient kb ≤ 0.2.

[0185] (Postscript 16)

[0186] Based on the printing method described in Appendix 12, gloss data can be generated based on the hue of the image data.

[0187] (Postscript 17)

[0188] Based on the printing method described in Appendix 12, gloss data can be generated based on the grayscale values ​​of image data.

[0189] (Postscript 18)

[0190] Based on the printing method described in Appendix 12, it is possible to receive information on the angle of incidence and gloss, and generate gloss data based on the information on the angle of incidence and gloss.

[0191] (Postscript 19)

[0192] Based on the printing method described in any of Notes 11 to 18, it is possible to form at least two areas with different gloss levels through a single coating process.

[0193] (Postscript 20)

[0194] Based on the printing method described in any of Appendix 11 to Appendix 19, it is possible to form an area by applying a gloss liquid by forming dots within a predetermined unit area and forming a predetermined maximum number of dots without overlap within the unit area, and then forming new dots on the dots already formed within the unit area.

Claims

1. A printing apparatus, wherein, The printing apparatus includes: A gloss-forming section, which forms at least two areas with different gloss levels on a printing medium; and A printing image forming unit forms a printed image on the printing medium in the areas where at least two regions with different gloss levels are formed by the gloss forming unit. The gloss forming unit calculates the brightness of each pixel based on the following formula and the red, green, and blue gray values ​​of each pixel constituting the image data representing the printed image. Brightness = Coefficient kr × Red grayscale value + Coefficient kg × Green grayscale value + Coefficient kb × Blue grayscale value The gloss level of each pixel is determined based on the calculated brightness of each pixel. Gloss level data is generated to control the amount of gloss liquid applied based on the determined gloss level, and at least two regions with different gloss levels are formed using the gloss level data.

2. The printing apparatus according to claim 1, wherein, The gloss forming unit generates gloss data based on the hue of the image data.

3. The printing apparatus according to claim 1, wherein, The gloss forming unit generates gloss data based on the grayscale values ​​of the image data.

4. The printing apparatus according to claim 1, wherein, The gloss forming section forms at least two areas with different gloss levels through a single coating process.

5. A printing method, wherein, After forming at least two areas with different gloss levels on the printing medium, a printed image is formed in said areas. The brightness of each pixel is calculated based on the following formula and the red, green, and blue gray values ​​of each pixel constituting the image data representing the printed image. Brightness = Coefficient kr × Red grayscale value + Coefficient kg × Green grayscale value + Coefficient kb × Blue grayscale value The gloss level of each pixel is determined based on the calculated brightness of each pixel. Gloss level data is generated to control the amount of gloss liquid applied based on the determined gloss level, and at least two regions with different gloss levels are formed using the gloss level data.

6. The printing method according to claim 5, wherein, Glossiness data is generated based on the hue of the image data.

7. The printing method according to claim 5, wherein, Glossiness data is generated based on the grayscale values ​​of the image data.

8. The printing method according to claim 5, wherein, It receives information about the angle of incidence and gloss, and generates gloss data based on the information about the angle of incidence and gloss.

9. The printing method according to claim 5, wherein, At least two areas with different gloss levels are formed through a single coating process.

10. The printing method according to claim 5, wherein, The area is formed by applying the gloss liquid by forming dots within a predetermined unit area and forming a pre-set maximum number of dots without overlap within the unit area, and then forming new dots on the dots already formed within the unit area.

Images