Method for producing a laminate and printing system

Abstract

To provide a laminate having colored metallic luster.SOLUTION: A laminate includes: a substrate 10 including a metallic luster surface having metallic luster; and a color layer 20 laminated on the metallic luster surface. The color layer 20 has an arithmetic average height and a transmission density positioned in a region downward from a straight line expressed as (y=-0.1067x+0.8) on a coordinate of an arithmetic average height x (μm) and a transmission density y.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a method for producing a laminate and a printing system.

Background Art

[0002] In order to improve the design property, a technique for forming a metallic gloss surface or a sub-metallic gloss surface (hereinafter also collectively referred to as a metallic-like gloss surface) on the surface of various members has been developed. As such a technique, Patent Document 1 discloses a method for forming a metallic gloss surface by printing with metallic ink.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The inventor of the present application has found that a colored metallic-like gloss can be obtained by printing a color layer in a suitably controlled manner on the above-described metallic-like gloss surface (which may be the surface of a metallic film formed by, for example, a metal plate, vapor deposition, etc., in addition to that formed by the technique of Patent Document 1).

[0005] An object of the present invention is to provide a method for producing a laminate having a colored metallic-like gloss and a printing system capable of producing a laminate having a colored metallic-like gloss.

Means for Solving the Problems

[0006] The laminate according to the first aspect of the present invention includes a substrate having a metallic-like gloss surface having a metallic-like gloss, and a color layer laminated on the metallic-like gloss surface. The color layer has an arithmetic mean height and a transmission density located in a region below a straight line represented by (y = -0.1067x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y.

[0007] According to the above configuration, a colored metallic luster can be obtained by the color layer having the above characteristics.

[0008] The color layer laminated on the metallic luster surface may be formed to cover the metallic luster surface or may be provided on a part of the metallic luster surface (hereinafter, the same applies to the color layer laminated on the metallic luster surface). The metallic luster surface of the base material may be, for example, at least a part of at least one surface of the base material (hereinafter, the same applies to the metallic luster surface).

[0009] The color layer has a ΔL* of 10 or more and a LogHAZE of 300 or more. It may be like this.

[0010] According to the above configuration, a colored metallic luster can be obtained by the color layer having the above characteristics.

[0011] The arithmetic mean height and the transmission density of the color layer are located in a region below a straight line represented by (y = -0.133x + 0.8) on the coordinates. It may be like this.

[0012] According to the above configuration, a colored metallic luster can be obtained by the color layer having the above characteristics.

[0013] The base material includes a base member and a metallic luster layer formed on the base member with metallic ink and having the metallic luster surface. It may be like this.

[0014] According to the above configuration, by providing a metallic luster layer, a colored metallic luster can be obtained. The metallic luster layer may be provided, for example, on at least a part of at least one surface of the base member.

[0015] The laminate according to the second aspect of the present invention includes a base material having a metallic luster surface with metallic luster, and a color layer laminated on the metallic luster surface. The color layer has an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y.

[0016] According to the above configuration, a colored metallic luster can be obtained by the color layer having the above characteristics.

[0017] The color layer may have a ΔL* of 35 or more and a LogHAZE of 700 or more. This may be done.

[0018] According to the above configuration, a matte and colored metallic luster can be obtained by the color layer having the above characteristics.

[0019] The color layer may have an Rspec of 50 or more. This may be done.

[0020] According to the above configuration, a mirror-like and colored metallic luster can be obtained by the color layer having the above characteristics.

[0021] The color layer may include a first part having a ΔL* of 35 or more and a LogHAZE of 700 or more, and a second part having an Rspec of 50 or more. This may be done.

[0022] According to the above configuration, metallic lusters with different textures can be expressed by the first part and the second part.

[0023] The base material is such that at least the metallic tone glossy surface is made of metal. It may be like this.

[0024] According to the above configuration, since the metallic tone glossy surface is made of metal, a metallic tone gloss can be easily obtained. Note that the base material may be made of metal, for example, or may be a non-metallic base material on which a metal film or the like having a metallic tone glossy surface is formed.

[0025] The laminate according to the third aspect of the present invention is a base material provided with a metallic tone glossy surface having a metallic tone gloss, and a color layer laminated on the metallic tone glossy surface. At least a part of the color layer is formed with a thickness through which light reflected by the metallic tone glossy surface can pass, and colors the metallic tone gloss.

[0026] According to the above configuration, since the color layer can transmit light, a colored metallic tone gloss can be obtained.

[0027] The color layer has an uneven shape, and at least the concave portions transmit light reflected by the metallic tone glossy surface. It may be like this.

[0028] According to the above configuration, since the concave portions can transmit light, a colored metallic tone gloss can be obtained.

[0029] A method for producing a laminate according to the fourth aspect of the present invention is a first step of preparing a base material provided with a metallic tone glossy surface having a metallic tone gloss, and a second step of printing a color layer on the metallic tone glossy surface by an inkjet method. In the second step, at least a part of the color layer is formed with a thickness through which light reflected by the metallic tone glossy surface can pass.

[0030] According to the above configuration, a colored metallic luster can be obtained by the color layer that can transmit the light.

[0031] The second step includes a second-1 step of selecting any one of a plurality of prepared printing conditions for printing the color layer that adds color to the metallic luster, and a second-2 step of printing the color layer based on the printing conditions selected in the second-1 step. It may be like this.

[0032] According to the above configuration, a colored metallic luster can be easily obtained by using the prepared printing conditions.

[0033] The first step includes a selection step of selecting, as the base material, either (1) a first base material including a base member and a metallic luster layer formed of metallic ink on at least a part of the base member and having the metallic luster surface, or (2) a second base material having a metallic portion forming the metallic luster surface. When the first base material is selected in the selection step, each of the plurality of printing conditions is a condition for printing the color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.1067x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y. When the second base material is selected in the selection step, each of the plurality of printing conditions is a condition for printing the color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y. It may be like this.

[0034] According to the above configuration, according to the material of the metallic luster surface, the color layer can be printed under suitable printing conditions for obtaining a colored metallic luster.

[0035] The printing system according to the fifth aspect of the present invention A printing mechanism capable of printing on a metallic lustrous surface having a metallic luster by means of a radiation-curable ink in an inkjet manner, and a printing control unit that controls the printing mechanism and prints a color layer on the metallic lustrous surface by means of the printing mechanism, wherein the printing control unit prints the color layer to have a thickness such that light reflected by the metallic lustrous surface and transmitted through at least a part of the color layer is transmissible.

[0036] According to the above configuration, a colored metallic luster can be obtained by the color layer that allows the light to pass through.

[0037] The printing control unit acquires at least one printing condition from a plurality of printing conditions stored in a storage unit for printing the color layer that adds color to the metallic luster, and prints the color layer based on the acquired at least one printing condition. This may be done.

[0038] According to the above configuration, it is not necessary for the user to set printing conditions, and a colored metallic luster can be easily obtained.

[0039] The printing conditions can be edited by the user, and the printing control unit prints the color layer based on the edited printing conditions. This may be done.

[0040] According to the above configuration, a metallic luster colored to the user's preference can be easily obtained.

[0041] Each of the plurality of printing conditions is a condition for printing the color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.1067x + 0.8) on a coordinate of the arithmetic mean height x (μm) and the transmission density y. This may be done.

[0042] According to the above configuration, a colored metallic luster can be obtained by the color layer having the above characteristics.

[0043] Each of the plurality of printing conditions is a condition for printing the color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y. It may be like this.

[0044] According to the above configuration, a colored metallic luster can be obtained by the color layer having the above characteristics.

[0045] The plurality of printing conditions are When the base material having the metallic luster surface is a first base material including a base member and a metallic luster layer formed of metallic ink on at least a part of the base member and having the metallic luster surface, one or more first printing conditions acquired by the printing control unit, and When the base material is a second base material having a metallic portion forming the metallic luster surface, one or more second printing conditions acquired by the printing control unit, and includes At least one of the one or more first printing conditions is different from at least one of the one or more second printing conditions. It may be like this.

[0046] According to the above configuration, a colored metallic luster can be obtained according to the material of the metallic luster surface.

[0047] One or more of the first printing conditions include conditions for printing the color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.1067x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y (it is preferable that all the first printing conditions are such conditions). One or more of the second printing conditions include the condition of printing the color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y (it is preferable that all the second printing conditions are this condition). It may be like this.

[0048] According to the above configuration, according to the material of the metallic lustrous surface, the color layer can be printed under suitable printing conditions for obtaining a colored metallic luster.

Effect of the Invention

[0049] According to the present invention, it is possible to provide a laminate having a colored metallic luster, a method for producing a laminate having a colored metallic luster, and a printing system capable of producing a laminate having a colored metallic luster.

Brief Description of the Drawings

[0050]

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[0051] (Embodiment 1) (Method for Producing a Laminate and Printed Matter) The method for producing a laminate (printed matter) according to Embodiment 1 of the present invention will be described. In this production method, as shown in FIG. 1, it has a first step S1 of preparing a base material having a metallic tone glossy surface, and a second step S2 of printing a color layer on the metallic tone glossy surface. Note that the metallic tone gloss includes metallic gloss and sub-metallic gloss.

[0052] The base material prepared in the first step S1 may be any material as long as it has a metallic tone glossy surface having a metallic tone gloss. For example, as shown in FIG. 2, a base material 10 is prepared in which a metallic tone gloss layer 12 having a metallic tone gloss (metallic gloss or sub-metallic gloss) is formed on a synthetic resin sheet 11 with metallic ink. The base material 10 may be a metal plate, or may be a member in which a metal film is formed as the metallic tone gloss layer 12 on a predetermined member by plating, vapor deposition, or the like. The sheet 11 does not have to be made of synthetic resin. For example, it may be paper, fabric, or the like.

[0053] In the second step S2, a color layer 20 is printed on the metallic gloss layer 12 of the substrate 10 with a UV (ultraviolet) curable ink having a predetermined color. As a result, a printed matter P with the color layer 20 printed on the substrate 10 as shown in FIG. 3 is formed. The color layer 20 forms an image. That is, in the second step S2, the image represented by the color layer 20 is printed. The color layer 20 may be a single color or may use two or more colors.

[0054] The UV (ultraviolet) curable ink contains, in addition to the coloring material that becomes the color of the color layer, a polymerization initiator and a resin (such as acrylate), such as a monomer or oligomer that polymerizes upon receiving ultraviolet irradiation.

[0055] The color layer 20 is formed by an inkjet method using an inkjet printer. The UV curable ink ejected by the inkjet method cures and adheres to the substrate 10, thereby forming the color layer 20. The color layer 20 is composed of a plurality (a large number) of dots 21 that constitute an image. Each dot 21 is formed by landing one or a plurality of drops of UV curable ink ejected from the print head of the inkjet printer at a predetermined location on the substrate 10 and then curing and fixing it by ultraviolet irradiation. A gap 22 is formed between each dot 21. This gap 22 may be formed by the adjacent dots 21 being separated from each other as shown in FIG. 4(a), or may be formed between the partially overlapping dots 21 as shown in FIG. 4(b).

[0056] The metallic tone gloss layer 12 is exposed from the gaps 22 between the dots 21. The dots 21 do not transmit the light reflected (e.g., specularly reflected) by the metallic tone gloss layer 12, but the gaps 22 (the portions where the thickness in the color layer 20 is "0". This portion is also part of the color layer 20) transmit the light reflected (e.g., specularly reflected) by the metallic tone gloss layer 12. Therefore, a person who views the printed matter P (hereinafter also referred to as an observer) visually recognizes the metallic tone gloss layer 12 through the gaps 22 together with the dots 21 of the color layer 20. As a result, the printed matter P is visually recognized as having a metallic tone gloss (color metallic gloss) of the color of the dots 21 (the color of the color layer 20). In particular, by making the gaps 22 so fine that they cannot be confirmed or are difficult to confirm with the naked eye, the printed matter P is visually recognized as having a uniformly colored metallic tone gloss in the portion where the color layer 20 is provided.

[0057] By adjusting the size of the gaps 22 (the size when viewing the color layer 20 etc. in plan view. The same applies to the size of the dots 21 etc.), the appearance of the printed matter P can be controlled. If the gaps 22 are too large, the dots 21 become rough, the coloring does not look uniform, or the colored color cannot be visually recognized (especially when the dots 21 are small). Also, if the gaps 22 are too small, most of the metallic tone gloss layer 12 is hidden by each of the dots 21, and the metallic tone gloss is lost.

[0058] In addition, when the dots 21 are connected as shown in Fig. 4(b), the thin film portion that is the connected portion (overlapped portion) may be made to have a thickness that transmits the light reflected (e.g., specularly reflected) by the metallic tone gloss layer 12. Also in this way, it is visually recognized as having a colored metallic tone gloss. Further, in both Fig. 4(a) and (b), the dots 21 (in the case of (b), the portions other than the thin film portion) may also be formed to have a thickness that allows light to pass through. In the case of (b), the dots 21 do not transmit light more than the thin film portion. Also in this way, it is visually recognized as having a colored metallic tone gloss.

[0059] The color layer 20 preferably has an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.1067x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y. In other words, the arithmetic mean height x (μm) and the transmission density y of the color layer 20 preferably satisfy the relationship of y < -8 / 75x + 0.8. Further, ΔL* of the color layer 20 after being laminated on the base material 10 is preferably 10 or more (more preferably 10 or more and 25 or less), and LogHAZE is preferably 300 or more (more preferably 400 or more). Further, it is more preferable that the arithmetic mean height and the transmission density of the color layer 20 are located in a region below a straight line represented as (y = -0.133x + 0.8) on the above coordinates. In other words, the arithmetic mean height x (μm) and the transmission density y of the color layer 20 preferably satisfy the relationship of y < -2 / 15x + 0.8. In order to have such characteristics, the discharge amount of the UV-curable ink per dot (the larger this amount, the larger the diameter of one dot), the dot density (the number of dots per unit area), and the period from when the UV-curable ink is discharged and landed on the base material 10 until the ink is cured (if this period is long, the ink spreads during that time, so the gap 22 becomes smaller and the thin film portion becomes thicker) may be adjusted. Note that the color layer 20 preferably has a reflection density of 0.5 or more.

[0060] The arithmetic mean height (Sa) is a parameter obtained by expanding Ra (arithmetic mean height of the line) to a surface, and represents the average of the absolute values of the height differences of each point with respect to the average surface of the surface. It is said that the rougher the surface, the higher the value. The arithmetic mean height (Sa) can be measured, for example, by a shape analysis laser microscope manufactured by KEYENCE Corporation: model number VK-X200Series, etc.

[0061] The transmission density increases as the object (color layer 20) becomes less transmissive to light. Incident light beam I 0、 When the transmitted light beam is I, the transmission density Dr is -log 10(I / I0) is calculated. There are two types of transmission density: parallel light density, which measures the light transmitted vertically from an object by irradiating the object with incident light perpendicular to it, and diffuse light transmission density, which measures the transmitted light in all directions. In this specification, the transmission density refers to the parallel light density. The transmission density can be measured, for example, using a D200-II transmission densitometer manufactured by Sakata Ink Engineering Co., Ltd. or a 361T desktop transmission densitometer manufactured by Exlite Co., Ltd.

[0062] When the transmission density of the color layer 20 is low, the metallic luster of the base material 10 can be visually recognized and a metallic feeling can be obtained. Therefore, basically, the lower the transmission density, the more preferable. On the other hand, when the arithmetic surface height is large, diffuse reflection occurs on the surface of the color layer 20, and the metallic feeling and color feeling are lost (the metallic luster cannot be seen, or the color by the color layer 20 cannot be seen). Therefore, when the arithmetic mean height x (μm) of the color layer 20 and the transmission density y satisfy the relationship y < -8 / 75x + 0.8, a preferable metallic feeling and color feeling can be obtained. When the arithmetic mean height x (μm) of the color layer 20 and the transmission density y satisfy the relationship y < -2 / 15x + 0.8, a more preferable metallic feeling and color feeling can be obtained. As described above, basically, the lower the transmission density, the more preferable. However, if it is too low, the coloring degree decreases, and there is a risk of losing the color feeling. For this reason, the transmission density is preferably 0.01 or more, and more preferably 0.05 or more.

[0063] The value of ΔL* is measured as follows. First, an axis perpendicular to the measurement sample surface (color layer printing surface) is set as 0° (reference), and the light reflected from the printing surface is measured by irradiating the printing surface with light from light sources placed at positions of 25°, 45°, and 75° respectively from the 0°. Here, the brightness obtained by reflecting the light from each light source on the printing surface is denoted as L25 (in the case of the 25° light source), L45 (in the case of the 45° light source), and L75 (in the case of the 75° light source), and the brightness difference between L25 and L75 is calculated as ΔL*. This value can be measured, for example, using a spectrophotometer manufactured by Konica Minolta.

[0064] The HAZE value of LogHAZE is the haze (unit: HAZE UNIT (HU)) measured at an incident light angle of 20° based on ASTM E430 / ISO 13803. This value can be measured, for example, by RHOPOINT-IQ manufactured by Konica Minolta or Micro-Haze Plus manufactured by BYK Gardner. The value of LogHAZE is obtained by LogHAZE = 1285×log[(HAZE value / 20) + 1] (where log is the common logarithm). The higher the value of LogHAZE, the more blurred the reflected image on the measurement surface (color layer 20) is (the color layer 20 has unevenness), and the lower the LogHAZE value, the higher the contrast of the reflected image on the measurement surface (color layer 20) is (the color layer 20 has no unevenness).

[0065] The reflection density increases as the object (color layer 20) reflects light. Incident light beam I 0、 Assuming the reflected light beam is I, the reflection density Dr is calculated by -log 10 (I / I0). The said reflection density can be measured, for example, by a 500 series spectrophotometer manufactured by X-Rite.

[0066] (Inkjet printer) As an inkjet printer for printing the color layer 20, for example, the inkjet printer 100 shown in FIG. 7 may be used. The inkjet printer 100 includes a conveyance mechanism 110, an ink tank 120, an ink supply mechanism 130, a print head 140, a drive mechanism 150, a radiation irradiation unit 160, and a control unit (controller) 170.

[0067] The conveyance mechanism 110 conveys the substrate 10 along the front-rear direction. The conveyance mechanism 110 is composed of a belt conveyor. The conveyance mechanism 110 may include a table on which the substrate 10 is placed and a drive mechanism for driving the table.

[0068] The ink tank 120 is an ink cartridge or an ink bottle that stores a radiation-curable ink (for example, a UV-curable ink), and is attached to the inkjet printer 100.

[0069] The ink supply mechanism 130 is a mechanism for supplying the radiation-curable ink in the ink tank 120 to the print head 140. The ink supply mechanism 130 includes a sub-tank for storing the radiation-curable ink, a supply pipe for supplying the radiation-curable ink in the ink tank 120 to the sub-tank, a circulation pipe for forming a circulation path for circulating the radiation-curable ink stored in the sub-tank through the print head 140, a valve for controlling the circulation of the radiation-curable ink in the circulation path, and a driving device for driving the valve.

[0070] The print head 140 discharges the radiation-curable ink supplied from the ink supply mechanism 130 by an inkjet method and applies it to the substrate 10. The print head 140 includes a storage chamber for storing the ink circulating in the circulation path of the ink supply mechanism 130, a piezoelectric element or a heater for extruding the radiation-curable ink stored in the storage chamber, and a nozzle for discharging the extruded radiation-curable ink. A plurality of sets of storage chambers, piezoelectric elements or heaters, and nozzles may be arranged side by side along the main scanning direction described later. Thereby, the radiation-curable ink can be discharged simultaneously for a plurality of pixels arranged along the main scanning direction.

[0071] The drive mechanism 150 moves the print head 140 in a direction orthogonal to the conveyance direction (sub-scanning direction) of the substrate 10. The drive mechanism 150 includes a carriage on which the print head 140 is mounted, and a moving mechanism for moving the carriage in the main scanning direction orthogonal to the sub-scanning direction. The moving mechanism includes a guide rail for supporting the carriage movably in the main scanning direction, a traction cable for pulling the carriage, and a winding mechanism for winding the traction cable (arranged in pairs at both ends of the guide rail).

[0072] The radiation irradiation unit 160 includes, for example, a light for irradiating radiation (e.g., ultraviolet rays) to the radiation-curable ink landed on the substrate 10. The radiation irradiation unit 160 is mounted on the above-described carriage.

[0073] The control unit 170 controls the conveying mechanism 110 (e.g., the belt conveyor or drive mechanism), the ink supply mechanism 130 (e.g., the drive device), the print head 140 (e.g., the piezoelectric element or heater), the drive mechanism 150 (e.g., the winding mechanism), and the light irradiation unit 160, and performs a printing process to apply radiation-curable ink to the substrate 10.

[0074] To perform this process, the control unit 170 includes a storage device (hard disk, flash memory, etc.) that stores programs and various data, a processor (CPU (Central Processing Unit), etc.) that executes the programs stored in the storage device and actually executes the printing process by using various data, a main memory for the processor, and various interfaces. The control unit 170 may be, for example, a personal computer.

[0075] (Printing process) The printing process is started when image data is supplied from an external host computer, etc. The image data includes data on whether or not radiation curable ink is to be ejected for each pixel. Note that, although the amount of ink ejected is constant here, the amount of ink ejected may be changed depending on the pixel.

[0076] First, the control unit 170 controls the transport mechanism 110 to move the substrate 10 to the printing start position. Next, the control unit 170 controls the drive mechanism 150 to move the print head 140 relative to the substrate 10 in the main scanning direction at a constant transport speed. During this movement, when the nozzle provided in the print head 140 reaches the position of the pixel (designated by the image data) where the radiation-curable ink is ejected, the control unit 170 controls the print head 140 to eject the radiation-curable ink in the form of droplets from the nozzle. During this period, the radiation irradiation unit 160 moves following the print head 140 and irradiates the radiation-curable ink landed on the substrate 10 with radiation to cure (fix) the radiation-curable ink. Note that the curing timing of the radiation-curable ink can be controlled by the distance between the radiation irradiation unit 160 and the nozzle of the print head 140 (that is, the size of the gap 22 and the thickness of the thin film portion can be controlled by the degree of spreading of the ink). Note that the interval from when the ink lands on the substrate 10 until the radiation is irradiated is preferably, for example, 1 to 60 seconds, more preferably 20 to 30 seconds.

[0077] Thereafter, the control unit 170 controls the transport mechanism 110 to feed the substrate 10 by one pixel in the sub-scanning direction. Thereafter, the control unit 170 ejects the ink while moving the print head 140 in the sub-scanning direction in the same manner as described above to print the second line. The control unit 170 repeats such operations to print each line. By printing each line, the entire color layer 20 (image) is printed. In this way, the control unit 170 controls the relative movement of the print head 140 with respect to the substrate 10 (the substrate 10 side may be moved) to print any one of the color layers 20.

[0078] A plurality of nozzles may be provided along the main scanning direction in the print head 140. In that case, the control unit 170 feeds the medium in the main scanning direction by the number of pixels of the nozzles.

[0079] By adjusting the curing timing of the UV curable ink according to the distance between the radiation irradiation unit 160 and the nozzles of the print head 140, etc., on the control unit 170 side, by controlling the interval at which the ink is ejected (dot density) and the amount of ink per dot, the size of the gap 22 and the thickness of the thin film portion can be controlled, whereby each numerical value such as the above ΔL* can be controlled, and the appearance of the printed matter P (such as the degree of coloring with respect to the metallic luster) can also be controlled.

[0080] (Modification Example 1) As another aspect of the printed matter P, a printed matter Q as shown in FIG. 5 may be formed. The printed matter Q includes a color layer 30 instead of the color layer 20. The color layer 30 includes dot portions 31 corresponding to the dots 21 and thin film portions 32 that connect the dot portions 31 to each other. The thin film portions 32 are integrally formed with the dot portions 31 by UV-curable ink. The thin film portions 32 can be formed by taking a longer time than in the case of FIG. 3 from the time when a drop of UV-curable ink from the print head 140 lands on the base material 10 until ultraviolet rays are irradiated onto the UV-curable ink. By taking a longer time, the UV-curable ink constituting each dot portion 31 spreads and connects accordingly, and the thin film portions 32 can be formed. In addition to or instead of adjusting the time, the thin film portions 32 may be formed by increasing the amount of ink per dot or increasing the dot density. Concavities and convexities are formed by the thin film portions 32 and the dot portions 31. The thickness of the thin film portions 32 is formed to be a thickness that allows light to pass through, and transmits the light reflected (e.g., specularly reflected) by the metallic gloss layer 12. The observer visually recognizes the metallic gloss layer 12 through the thin film portions 32 together with the dot portions 31 of the color layer 30. Thereby, the printed matter Q is visually recognized as having a metallic gloss of the color of the dot portions 31 (the color of the color layer 30). In particular, by making the concavities and convexities formed by the thin film portions 32 and the dot portions 31 so fine that they cannot be confirmed or are difficult to confirm with the naked eye, the printed matter Q is visually recognized as having a uniformly colored metallic gloss in the portion where the color layer 30 is provided. Note that the dot portions 31 may also be formed to have a thickness that allows light to pass through. In this case, the dot portions 31 transmit less light than the thin film portions 32. Even in such a case, the printed matter Q is visually recognized as having a metallic gloss of the color of the dot portions 31 (the color of the color layer 30).

[0081] (Modification 2) As another aspect of the printed matter P, a printed matter R as shown in FIG. 6 may be formed. The printed matter R includes a color layer 40 instead of the color layer 20. The color layer 40 is a flat layer having a uniform thickness. The color layer 40 can be formed by taking a longer time than in the cases of FIGS. 3 and 5 from when a drop of UV-curable ink from the print head 140 lands on the base material 10 until ultraviolet rays are irradiated onto the UV-curable ink. By taking a longer time, the UV-curable ink constituting each dot spreads and connects accordingly, and finally the unevenness disappears, and the thickness of the color layer 40 obtained by curing the UV-curable ink becomes uniform. In addition to or instead of adjusting the time, the color layer 40 may be formed by increasing the amount of ink per dot or increasing the dot density. The thickness of the color layer 40 is formed to be a thickness through which light can pass, and transmits the light reflected (for example, specular reflection) by the metallic gloss layer 12. The observer visually recognizes the metallic gloss layer 12 through the color layer 40. Thereby, the printed matter R is visually recognized as having the metallic gloss of the color of the color layer 40.

[0082] (Modification 3) Regarding the above color layer 30 and color layer 40, it is preferable to have the same characteristics as the characteristics of the color layer 20 described above (such as the arithmetic mean height x (μm) and the transmission density y satisfying the relationship y < -8 / 75x + 0.8).

[0083] (Modification 4) The ink used to form the color layers 20, 30, and 40 is not limited to UV-curable ink, and any radiation-curable ink that cures by radiation may be used. Examples of the radiation-curable ink include, in addition to the above UV-curable resin, an electron beam-curable resin that cures by electron beam. Further, the ink used to form the color layers 20, 30, and 40 may be other types of ink that can be printed by an inkjet printer, such as aqueous ink (including latex ink), solvent ink, etc. Further, the inkjet printer 100 may be configured to be able to print such other types of ink.

[0084] (Modification 5) The dot densities of the color layers 20 and 30 do not have to be uniform. For example, by providing areas with high and low dot densities, arbitrary patterns, such as a gradation pattern, may be formed on the color layers 20 and 30. In this case, a metallic luster having a color corresponding to the pattern, for example, a metallic luster exhibiting a color gradation, can be obtained.

[0085] (Modification Example 6) The means for laminating the color layers 20, 30, and 40 on the base material 10 is not limited to an inkjet printer, and any other laminating device such as a screen printing method may be used as long as fine dots having a predetermined gap 22 can be formed.

[0086] (Modification Example 7) In FIGS. 2, 3, 5, and 6, the surface of the metallic luster layer 12 is shown as flat, but the surface of the metallic luster layer 12 may have irregularities. The irregularities on the surface of the metallic luster layer 12 can affect the surface parameters (e.g., arithmetic mean height, etc.) of the color layers 20, 30, and 40 laminated on the metallic luster layer 12, but there is no problem as long as the parameters of the color layers 20, 30, and 40 finally formed on the surface of the metallic luster layer 12 are within the above-mentioned predetermined range.

[0087] (Embodiment 2) Hereinafter, Embodiment 2 will be described. The descriptions not mentioned in the following description shall be in accordance with the descriptions of the above Embodiment 1 and modification examples (hereinafter referred to as Embodiment 1 etc.).

[0088] (Printed Matter) FIG. 8 shows a printed matter (laminated body) S according to Embodiment 2. The printed matter S has a base material 50 and a color layer 60. The base material 50 is made of a metal plate or the like made of metal. The surface of the base material 50 is a metallic luster surface having a metallic luster (here, particularly a metallic luster). The base material 50 may be in the form of a metal plate or a metal sheet, or may be a member in which a metal film is formed on a material other than metal, such as a PET (Polyethylene terephthalate) sheet, a synthetic resin sheet such as an acrylic plate, paper, cloth, etc. by plating, vapor deposition, or the like. The base material 50 may be, for example, a member in which at least the surface on which the color layer 60 is printed is made of metal (including the metal film). Examples of the metals include aluminum, iron, copper, stainless steel, etc.

[0089] The color layer 60 is formed by inkjet printing using UV-curable ink, similarly to the color layer 30. The color layer 60 includes dots 61 that are convex portions and thin film portions 62 that are connected to each of the dots 61, similarly to the color layer 30. The thin film portions 62 are formed integrally with the dots 61 by UV-curable ink. The thin film portions 62 and the dots 61 form unevenness. For the description of the color layer 60, reference can be made to the description of the color layer 30. The dots 61 correspond to the dots 31 of the color layer 30, and the thin film portions 62 correspond to the thin film portions 32 of the color layer 30. The color layer 60 may not have gaps between the dots 61 as the color layer 20 has, may have gaps (the gaps are also part of the color layer 60) like the color layer 20, or may be flat like the color layer 40 (for these descriptions, reference can be made to the descriptions of the color layer 20 and 40). The color layer 60 (including the cases where there are gaps and where it is flat as described above) transmits part of the light from the outside and reflects the other part. Among the light from the outside, part of the light transmitted through the color layer 60 is reflected by the metallic luster surface of the base material 50, passes through the color layer 60 again, and is emitted outside the color layer 60. When the part of the light transmitted through the color layer 60 and the light reflected by the color layer 60 enter a person's eyes, the printed matter S is visually recognized by the person as having the color of the color layer 60 added to the metallic luster by the metallic luster surface (a colored metallic luster is obtained).

[0090] The color layer 60 may have an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y. In other words, the arithmetic mean height x (μm) and the transmission density y of the color layer 60 may satisfy the relationship of y < -1 / 16x + 0.8. With such a relationship, the color layer 60 can add color to the metallic luster of the base material 50, and the metallic luster colored by the color layer 60 is expressed (the condition is relaxed for the base material 50 compared to the case of the base material 10, that is, when the metallic luster of the base material 50 is expressed by metal). In addition to the above condition (y < -1 / 16x + 0.8), the ΔL* of the color layer 60 is preferably 35 or more, and the LogHAZE is preferably 700 or more. With these numerical values, the printed matter S has an appearance of being colored by the color layer 60 and having a rough (matte) metallic luster. Or, in addition to the above condition (y < -1 / 16x + 0.8), the Rspec of the color layer 60 may be 50 or more. With these numerical values, the printed matter S has an appearance of being colored by the color layer 60 and having a smooth (mirror finish) metallic luster. To have the above characteristics, it is advisable to adjust the discharge amount of the UV-curable ink per dot (the larger this amount, the larger the diameter of one dot), the dot density (the number of dots per unit area), and the period from discharging the UV-curable ink and landing it on the base material 50 until the ink is cured (if this period is long, the ink spreads during that time, so the gap between dots becomes smaller and the thin film part becomes thicker).

[0091] (Modification 1) At least a part of the surface of the base material 50 may be made of metal. The metallic part only needs to have a metallic luster. The color layer 60 may be formed in a region including at least a part of the metallic part of the base material 50. The base material 50 may be in a non-sheet form in addition to being in a sheet form.

[0092] (Embodiment 3) Next, Embodiment 3 will be described. The descriptions not mentioned in the following description are in accordance with the descriptions of Embodiment 1, etc., Embodiment 2, and the modification example (hereinafter also referred to as Embodiment 2, etc.).

[0093] (Printing System PS) Embodiment 3 relates to a printing system for forming any one of the base material color layers. As shown in FIG. 9, the printing system PS according to Embodiment 3 includes the inkjet printer 100 described in Embodiment 1 and a computer 300. The printing system PS prints any one of the color layers 20 to 40 on the base material 10 and the color layer 60 on the base material 50 to form any one of the printed matters P to S. Hereinafter, the base materials 10 and 50 are collectively referred to as the base material BS, and the color layers 20 to 40 and 60 are also collectively referred to as the color layer CL.

[0094] For the description of the inkjet printer 100, reference can be made to Embodiment 1. In particular, the ink tank 120 stores a plurality of radiation-curable inks (for example, a plurality of inks of different colors such as each color of CMYK (cyan, magenta, yellow, black)) for forming the color layer CL individually for each ink. The ink supply mechanism 130 supplies each of the plurality of radiation-curable inks in the ink tank 120 to the print head 140 individually. The print head 140 ejects each of the plurality of radiation-curable inks supplied from the ink supply mechanism 130 individually by an inkjet method and lands them on the base material 10 or 50. For each of the plurality of radiation-curable inks, a plurality of sets of the above-mentioned storage chambers, piezoelectric elements or heaters, and nozzles may be provided along the sub-scanning direction and / or the main scanning direction. The ejection / non-ejection and ejection amount of the radiation-curable ink are controlled individually for each nozzle.

[0095] The computer 300 is composed of various computers such as a personal computer and includes a storage unit 310, a control unit 320, an operation unit 330, and a display unit 340. Here, the computer 300 is a host computer that controls the inkjet printer 100 (gives instructions for printing, etc.).

[0096] The storage unit 310 consists of a non-volatile storage device such as a hard disk, an SSD (Solid State Drive), or a flash memory. The storage unit 310 stores various programs, data indicating print information, and the like.

[0097] The various programs described above are executed by the control unit 320, whereby various processes are executed (details will be described later).

[0098] The print information includes print conditions (details will be described later) when printing the color layer CL. The print conditions are selected by the user. The user is, for example, an operator who prints printed matter using the printing system PS, a purchaser of the printing system PS, and is the one who operates the computer 300 or the like to cause the inkjet printer 100 to perform printing. The color layer CL is printed based on the selected print conditions. An example of the print information is shown in FIG. 10. As the print information, there is provided first print information used when the substrate to be printed with the color layer CL is substrate 10 (a substrate provided with a metallic luster layer 12), and second print information used when the substrate is substrate 50 (a metallic substrate).

[0099] The storage unit 310 may store one or more (here, a plurality) of the first print information and one or more (here, a plurality) of the second print information. One piece of first print information and one piece of second print information each include an ID, print conditions, and preview data. The ID, print conditions, and preview image are stored in the storage unit 310 in association with each other for each piece of first print information and each piece of second print information.

[0100] The ID is information (such as "A1", "A2", "B1", "B2", etc.) that identifies each of the first print information and the second print information.

[0101] The printing conditions are the printing conditions when printing the color layer CL, and include the ejection amount of each ink and the irradiation mode, etc. The ejection amount is information (such as "ejection amount of C", "ejection amount of M", etc.) that specifies the ejection amount of ink per dot from each nozzle of the print head 140 (for example, when the ejection amount of ink per time is a fixed amount, the ejection amount is defined by the number of ink ejection times) for each radiation-curable ink (here, CMYK inks). The irradiation mode is information that specifies the period from when the UV-curable ink is ejected and lands on the substrate BS until the ink is cured. In the inkjet printer 100, since the radiation irradiation unit 160 and the print head 140 move together in the main scanning direction, the period can be changed by changing the moving speed according to the irradiation mode. Note that only ink ejection is performed when the print head 140 and the radiation irradiation unit 160 are moved one or more times in the main scanning direction at the same position in the sub-scanning direction, and then radiation irradiation is performed when the print head 140 and the radiation irradiation unit 160 are moved once again in the main scanning direction at the same position. In this case, the period from when the radiation-curable ink is ejected and lands on the substrate BS until the ink is cured can be adjusted by adjusting the standby time from the movement for ink ejection to the movement for radiation irradiation. The printing conditions may be any conditions that specify the conditions under which the characteristics (arithmetic mean height, transmission density, ΔL*, LogHAZE, reflection density) of the color layer CL become desired characteristics, and may include the number of dots per square inch, etc. The printing conditions are appropriately edited by the user.

[0102] Each of the printing conditions of all the first printing information stored in the memory unit 310 is preferably a condition for printing the color layers 20 to 40 having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.1067x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y. Further, each or at least one of the printing conditions is preferably a condition for printing the color layers 20 to 40 where ΔL* is 10 or more (more preferably 10 or more and 25 or less) and LogHAZE is 300 or more (more preferably 400 or more). Each or at least one of the printing conditions is preferably a condition for printing the color layers 20 to 40 having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.133x + 0.8) on the coordinates. Further, each or at least one of the printing conditions is preferably a condition for printing the color layers 20 to 40 where the reflection density is 0.5 or more. By these conditions, any one of the color layers 20 to 40 that adds color to the metallic luster of the base material 10 can be obtained.

[0103] Each of the printing conditions of all the second printing information stored in the storage unit 310 is preferably a condition for printing the color layer 60 having an arithmetic mean height and a transmission density located in a region below a straight line represented by (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y. In addition to this condition, each of the printing conditions or at least one of them is preferably a condition for printing the color layer 60 where (1) ΔL* of the color layer 60 is 35 or more and LogHAZE is 700 or more, or (2) Rspec of the color layer 60 is 50 or more. With these conditions, any one of the color layers 60 that adds color to the metallic luster of the base material 10 can be obtained. The color layer 60 printed under the condition of (1) gives a metallic luster with a rough (matte) texture. The color layer 60 printed under the condition of (2) gives a metallic luster with a smooth (near-mirror) texture. The printing conditions of all the second printing information stored in the storage unit 310 may be either the condition of (1) or the condition of (2) above, or a part of the printing conditions may be the condition of (1) above, another part may be the condition of (2) above, and the remaining part may be one or more other conditions. Thus, the plurality of printing conditions of each of the plurality of second printing information stored in the storage unit 310 preferably include the condition of (1) and the condition of (2) above, whereby metallic lusters with different textures can be expressed.

[0104] A part of each of the printing conditions of the first printing information and each of the printing conditions of the second printing information may be the same condition. However, there may be a case where the appearance of the metallic luster with added color is different between the base material 10 and the base material 50. Also, the printing conditions may be common to the base material 10 and the base material 50. For example, only the first printing information may be adopted (if it is a printing condition for printing a color layer that produces a colored metallic luster on the base material 10 (the metallic luster layer 12 made of metallic ink), a color layer that produces a colored metallic luster can also be obtained on the base material 50).

[0105] The above printing conditions are obtained through experiments and the like. Specifically, the color layer is printed on the base material BS under various printing conditions, and among these various printing conditions, the condition under which the printed color layer colors the metallic luster of the base material BS (adds color without losing the metallic luster), that is, the color layer CL (the color layer CL that satisfies the above conditions), is adopted as the printing condition for the above printing information.

[0106] The preview image is an image representing the surface of any one of the printed matters P to S when the color layer CL is printed under the corresponding printing conditions, that is, an image representing the colored metallic luster. The preview image is displayed on the display unit 340 for reference when the user selects the printing conditions. The preview image may be, for example, an image of a colored metallic luster obtained when the color layer CL is printed on a silver metallic luster surface. In this case, the metallic luster surfaces of the base material 10 and the base material 50 used for printing may also be silver according to the preview image. Even when the base material 10 and the base material 50 used for printing are not silver, the user can grasp to a certain extent the state of the metallic luster after the formation of the color layer CL with reference to the preview image. Considering the case where the base material 10 and the base material 50 are colors other than silver (for example, copper color, etc.), the data of each image representing the surface of any one of the printed matters P to S when the color layer CL is printed on metallic luster surfaces of various colors, that is, the colored metallic luster, may be prepared as the data of the above image.

[0107] The control unit 320 actually executes the processes (processes such as receiving the selection of printing conditions, displaying the preview image, editing the printing conditions, and causing the inkjet printer 100 to print the color layer CL based on the printing conditions) executed by the computer 300 by executing various programs stored in the storage unit 310.

[0108] The operation unit 330 receives the operations of the user (operations such as selecting printing conditions and editing printing conditions). The operation unit 330 is composed of a keyboard, a mouse, and the like.

[0109] The display unit 340 displays the preview image and the like, and is configured to include a liquid crystal display device or the like.

[0110] (Operation of the printing system PS) Hereinafter, the operation of the printing system PS will be described. Here, it is assumed that the original image G in FIG. 11 is prepared as the original image (the image to be actually printed) represented by the color layer CL. The original image G is created by drawing software such as the computer 300. The original image G includes a first image G1 and a second image G2 (for example, the surrounding image adjacent to the first image G1). Note that the original image G is not limited to the form in FIG. 11 and can be in various forms.

[0111] The control unit 320 of the computer 300 executes the printing process shown in FIG. 12 according to the program stored in the storage unit 310. It is assumed that the base material 10 or the base material 50 is set in the inkjet printer 100 before the execution of the process.

[0112] In the printing process, the control unit 320 first displays on the display unit 340 a screen for selecting whether the base material set in the inkjet printer 100 is the base material 10 or the base material 50, and accepts a selection operation of the base material using the operation unit 330 by the user (step S21).

[0113] When the control unit 320 receives the selection operation, it receives the selection of printing conditions (step S22). Specifically, when the user selects the base material 10 by operating the operation unit 330, the control unit 320 displays, on the display unit 340, the preview images included in the first printing information together with the original image G. When the user selects the base material 50 by operating the operation unit 330, the control unit 320 displays, on the display unit 340, the preview images included in the second printing information together with the original image G. Thereafter, the control unit 320 receives an operation for which printing condition to apply to each part (the first image G1 and the second image G2) of the original image G (step S22). For example, the user uses the operation unit 330 to perform drag and drop to move a desired preview image to each part of the original image G. As a result, for each part, the printing condition corresponding to the moved preview image is applied (selected) to the part at the movement destination.

[0114] When the control unit 320 receives the selection of printing conditions, it displays the content of the printing conditions (particularly, numerical values such as the discharge amount) on the display unit 340 and receives an editing operation of the printing conditions (step S23). Note that the printing conditions after being edited may be stored in the storage unit 310 as the edited printing conditions (and may be made selectable when selecting printing conditions after the next time).

[0115] When an operation to end the editing without performing an editing operation is performed, or when an editing operation is performed, the control unit 320 supplies an instruction to print the original image G under the printing conditions selected in step S22 (when there is no editing) or the post-editing printing conditions to the inkjet printer 100 (step S24). For example, the control unit 320 creates new image data in which the printing conditions or the post-editing printing conditions are applied to each part of the original image G, and supplies the created image data to the inkjet printer 100 together with an instruction to print. The control unit 170 of the inkjet printer 100 performs a printing operation based on the supplied instruction (for example, the above-mentioned image data), and prints the color layer CL on the base material BS. As a result, the color layer CL is printed according to the printing conditions selected in step S22 or the post-editing printing conditions, and the image represented by the color layer CL is printed. Since the post-editing printing conditions are based on the printing conditions selected in step S22, the printing of the color layer CL according to the post-editing printing conditions can also be said to be printing based on the printing conditions selected in step S22.

[0116] By the above-described processing, for example, when the substrate set in the inkjet printer 100 is the substrate 50 (when the printing conditions of the second printing information are selected), the following condition A is selected as the printing condition for the portion corresponding to the first image G1 of the image G in the color layer CL, and the following condition B may be selected as the printing condition for the portion corresponding to the second image G2 of the image G in the color layer CL. Condition A is a printing condition for printing a color layer having an arithmetic mean height and a transmission density located in a region below the straight line represented by (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y, with ΔL* being 35 or more and LogHAZE being 700 or more. Condition B is a printing condition for printing a color layer having an arithmetic mean height and a transmission density located in a region below the straight line represented by (y = -0.0625x + 0.8) on the coordinates of the arithmetic mean height x (μm) and the transmission density y, with Rspec being 50 or more. In the printed matter S in which the color layer CL is printed under each of these printing conditions, the portion of the first image G1 of the image G has a rough texture (matte finish) metallic luster, and the portion of the second image G2 of the image G has a smooth texture (mirror finish) metallic luster. Therefore, the printed matter S has high designability with different textures depending on the printed areas or the positions visually recognized by the observer. For example, the first image G1 and the second image G2 may be printed with the same color, for example, the same ink (when the color is represented by a plurality of colors of ink, the ink with the same discharge amount ratio for the first image G1 and the second image G2), and even in this case, a metallic luster with the same color but different textures can be obtained, and high designability can be obtained. The first image G1 and the second image G2 may be printed with different colors, for example, different inks (when the same plurality of inks are used for the first image G1 and the second image G2, the inks with different discharge amount ratios), and even in this case, a metallic luster with different colors and different textures can be obtained, and high designability can be obtained.

[0117] The actually printed image (the image represented by the color layer CL) is not limited to being created by the method as described above. For example, an image to be printed is prepared, and among the image, the part to be printed with the color layer CL (that is, the part where a colored metallic luster is to be expressed) and its printing conditions are selected or input (including editing) by the user (for the parts other than the part where the color layer CL is printed, for example, they may be solid-colored so that no metallic luster appears), and an image to be actually printed may be created. Also, the image printed above may be one that has been previously created by drawing software or the like including the position of the color layer CL and its printing conditions.

[0118] When the base material 10 is selected and the printing conditions of the first printing information are selected, the first image G1 may be the part where the color layer CL is printed, and the second image G2 may be the part where the color layer CL is not printed. In this way, the color layer CL may be printed only on a part of the base material 10 and the base material 50, and printing may not be performed on other parts.

[0119] According to the above configuration, it is possible to express metallic colors such as silver or stainless steel using conventional inkjet metallic inks, and it is also possible to express various color tones by printing a color layer using color ink. In the above configuration, instead of using a color metallic ink obtained by mixing color ink with metallic ink, a metallic luster surface prepared in advance, for example, one surface of the base material 10 formed with a metallic luster surface using metallic ink on a non-metallic material sheet such as a PET sheet or paper, or one surface of the metallic sheet-like base material 50 such as an aluminum foil, is printed using color ink, so that a colored metallic luster (colored metallic luster) can be expressed.

[0120] In the above description, since the printing conditions for the base material 10 (printing conditions for the first print information) and the printing conditions for the base material 50 (printing conditions for the second print information) are prepared, the color layer CL can be printed under suitable printing conditions for obtaining a colored metallic luster according to the material of the metallic luster surface of the base material. Also, since the printing conditions are prepared in advance, for the user, there is no need to set the printing conditions by oneself, and a printed matter having a colored metallic luster can be easily obtained. Further, by making the printing conditions editable, the preferences of the user can also be reflected. Furthermore, as the printing conditions for the second print information, by preparing the conditions for printing the color layer having ΔL* of 35 or more and LogHAZE of 700 or more, and the conditions for printing the color layer having Rspec of 50 or more, colored metallic lusters with different textures (matte or mirror finish) can be obtained. Note that the color layer CL may be printed uniformly under one printing condition, or may be printed under different printing conditions according to the region on the base material 50 as described above.

[0121] (Modification Example 1) First, as the base material BS on which the color layer CL is printed, either a base member (which may be other than the sheet 11 and may not be sheet-shaped) and a metallic luster layer 12 formed by metallic ink on at least a part of the base member and having a metallic luster surface, that is, the base material 10, or a base material 50 having a metallic portion forming the metallic luster surface may be selected. In such a case, the inkjet printer 100 may have a function of printing the metallic luster layer 12 with metallic ink. When the base material 10 is selected, the sheet 11 of the base material 10 may be set in the inkjet printer 100, and the metallic luster layer 12 may be printed by the inkjet printer 100 to form the base material 10. When the base material 10 is selected, the color layer CL may be printed under the printing conditions for the first print information, and when the base material 50 is selected, the color layer CL may be printed under the printing conditions for the second print information.

[0122] (Modification Example 2) The above printing information (printing conditions, etc.) may be stored in the inkjet printer 100, such as in the storage device of the control unit 170. In this case, the selection and editing of the printing conditions may be performed using the display unit and the operation unit provided in the inkjet printer 100. Further, the above printing information may be stored outside the computer 300, such as in a server capable of communicating with the computer 300, and may be supplied to the computer 300 each time the printing conditions are selected.

[0123] The printing system PS may have a printing mechanism that performs printing by an inkjet method and a printing control unit that controls the printing mechanism. When printing conditions, etc. are stored outside the computer 300, such as in the computer 300 or a server, for example, the printing mechanism becomes the inkjet printer 100, and the printing control unit becomes the computer 300. When printing conditions, etc. are stored in the inkjet printer 100, for example, the printing mechanism becomes a part of the inkjet printer 100 other than the part that stores the processing and data of the control unit 170, etc. (particularly, the print head 140 and the part that relatively moves the print head 140 with respect to the base material BS), and the printing control unit becomes the part of the inkjet printer 100 that stores the processing and data of the control unit 170, etc.

[0124] (Example 1) (Adjustment of metallic gloss base) First, a gloss ink having the following composition was adjusted. · 95 parts by mass of an ultraviolet curable resin (manufactured by Mimaki Engineering Co., Ltd., LH-100 clear ink) · 5 parts by mass of an aluminum pigment

[0125] For the adjustment of the gloss ink, first, a polyethylene terephthalate film with a smooth surface (surface roughness Ra of 0.02 μm or less) was prepared. Subsequently, silicone oil was applied to the entire one surface of this film. On the side where the silicone oil was applied, a film composed of aluminum (hereinafter, also simply referred to as "aluminum film") was formed using a vapor deposition method. Subsequently, the film on which the aluminum film was formed was placed in LH-100 clear ink (manufactured by Mimaki Engineering Co., Ltd.) and irradiated with ultrasonic waves to peel and pulverize the aluminum film from the film. Next, this was put into a homogenizer and pulverized for about 8 hours to obtain a gloss ink in which flaky aluminum particles were dispersed. The concentration of aluminum particles in this gloss ink was 5% by weight.

[0126] Next, using an inkjet printer (manufactured by Mimaki Engineering Co., Ltd., flatbed type (model number UJF-7151plus)), this gloss ink was printed in a strip shape on a flexible film (manufactured by Higashiyama Film Co., Ltd., HK-31WF) under the conditions of 600×900 dpi and 16 passes. In each pass, the flexible film was irradiated with ultraviolet rays after sequentially setting a waiting time of 19.00 seconds from the timing when the gloss ink was applied by the printer head. This metallic gloss base had a LogHAZE of 384.2, an Sa (arithmetic mean height) of 0.76 μm, a coating film thickness of 4.56 μm, and an absolute reflectance of 26.76%.

[0127] (Monochrome printing) Using cyan ultraviolet curable ink (manufactured by Mimaki Engineering Co., Ltd., LH-100 cyan (C)), printing was performed on the above-mentioned metallic gloss base by an inkjet printer (UJF-7151plus, manufactured by Mimaki Engineering Co., Ltd.) according to the conditions shown in the following table to obtain a monochrome printing sample.

[0128]

Table 1

[0129] (Printing conditions common to samples) · Head temperature: 45°C · Printing environment temperature (including media): 25°C

[0130] In the table, "number of drops" indicates the number of dots per square inch. For example, in C1, printing is performed with a set value of 440,464 drops, but there is an error of about several thousand between the set value and the measured value, so the significant figures of the number of drops in the table are two digits.

[0131] In the table, "UV irradiation interval" indicates the time from when the ink droplet ejected from the inkjet nozzle lands on the media until the landed ink droplet is irradiated with ultraviolet light.

[0132] In the table, "dot size" indicates the diameter of one dot on the media after ultraviolet curing. This diameter is the arithmetic mean value when measured using an optical microscope (model number: VH-X6000 Series, manufactured by KEYENCE). The dot size was set to a predetermined size by adjusting the drive waveform of ink ejection in the UJF-7151plus.

[0133] In the table, "film thickness" indicates the thickness of the ink layer after ultraviolet curing formed on the media. The film thickness was measured by a shape analysis laser microscope (model number VK-X200 Series, manufactured by KEYENCE).

[0134] (CMYK printing) Furthermore, using cyan and magenta ultraviolet-curable inks (manufactured by Mimaki Engineering Co., Ltd., LH-100 cyan (C) and LH-100 magenta (M)), with a dot pattern in which dots of each ink are arranged alternately, and according to the conditions shown in the following table, printing was performed on the above-described metallic gloss substrate using the above-described inkjet printer to obtain blue mixed-color printing samples. Similarly, using cyan, magenta, and yellow ultraviolet-curable inks (manufactured by Mimaki Engineering Co., Ltd., LH-100 cyan (C), LH-100 magenta (M), and LH-100 yellow (Y)), mixed-color printing samples of process black were obtained. In the following table, blue mixed-color printing samples are indicated by "B" and a combination of numbers (e.g., "B1"), and mixed-color printing samples of process black are indicated by "PB" and a combination of numbers (e.g., "PB1").

[0135]

Table 2

[0136] In addition, in mixed-color printing, the "number of drops" indicates the total number of drops of all-color inks. Since the set values of the number of drops of each color ink are the same, the number of drops per color is obtained by dividing the number of drops in the table by 2 (in the case of blue) or 3 (in the case of process black).

[0137] (Example 2) Monochromatic printing and mixed-color printing samples were obtained according to the conditions shown in the following table in the same manner as in Example 1, except that a color layer was printed directly with color ink on a sheet-like substrate (metallic tone gloss surface by metal) having an aluminum metal film vapor-deposited on the surface of a PET sheet.

Table 3

[0138] (Various Tests) For each of the above single-color printing samples and multi-color printing samples, the arithmetic mean height (Sa value), transmission density, ΔL*, LogHAZE, and Rspec were measured. In addition, for each sample, a sensory test regarding the film state and designability was conducted.

[0139] The arithmetic mean height (Sa value) was measured by a shape analysis laser microscope: model VK-X200Series (manufactured by KEYENCE) based on ISO-25178 (surface roughness).

[0140] The reflection density was measured by a 500 series spectrophotometer (manufactured by X-Rite) based on ISO-5 / 4 (optical system for reflection density measurement).

[0141] The transmission density was measured by a D200-II transmission densitometer (manufactured by Sakata Inx Engineering) based on ISO-5 / 2 (optical system for transmission density measurement).

[0142] ΔL* was measured by a spectrophotometer CM-512m3A (manufactured by Konica Minolta). Taking the axis perpendicular to the measurement sample surface (printing surface) as 0°, the light sources are placed at positions of 25°, 45°, and 75° respectively at angles from the 0°. By reflecting the light irradiated from each light source on the printing surface and receiving the reflected light from the position of 0°, the L25, L45, and L75 values of each brightness were obtained. ΔL* was obtained by calculating the difference between L25 and L75.

[0143] LogHAZE was measured at an incident light angle of 20° by a gloss meter appearance analyzer: model RHOPOINT-IQ (manufactured by Konica Minolta) based on ISO-13803.

[0144] Rspec is the value measured for the peak reflection in a very narrow angular range of the specular reflection direction (20°) ± 0.0991° when irradiating light at an incident angle of 20°. The higher this value, the more specular reflection (mirror reflection) can be said to occur. Rspec was measured at an incident light angle of 20° by a gloss meter appearance analyzer: model RHOPOINT-IQ (manufactured by Konica Minolta).

[0145] In the sensory test regarding the film state (color feeling), 12 panelists were asked to judge based on whether they felt that each sample had a colored appearance with a color feeling. If 8 or more panelists judged it to be colored, it was evaluated as "◎"; if 5 to 7 panelists judged it to be colored, it was evaluated as "○"; if 4 or fewer panelists judged it to be colored, it was evaluated as "×".

[0146] In the sensory test regarding the design property (metallic luster feeling), 12 panelists were asked to judge whether each sample had a metallic feeling on its surface. If 8 or more panelists judged it to have a metallic feeling, it was evaluated as "○"; if 8 or fewer panelists judged it to have a metallic feeling, it was evaluated as "×".

[0147] The above test results are summarized in the following table.

[0148]

Table 4

[0149]

Table 5

[0150]

Table 6

[0151] When LogHAZE is plotted against ΔL* for samples with a film state of "◎" and a design property of "○", samples with a film state of "○" and a design property of "○", and samples with either the film state or the design property being "×", it becomes as shown in Fig. 13. Also, when the transmission density is plotted against Sa for these samples, it becomes as shown in Fig. 14.

[0152] First, from the results of Fig. 13, it was found that for samples with a film state of "◎" or "○" and a design property of "○", LogHAZE is 400 or more, and ΔL* is 10 or more and 25 or less.

[0153] Also, from the results in Fig. 14, it was found that for the samples with a film state of "◎" and a designability of "○", when Sa is x and the transmission density is y, x and y satisfy the relational expression y < -8 / 75x + 0.8. Furthermore, for the samples with a film state of "◎" or "○" and a designability of "○", it was similarly found that x and y satisfy the relational expression y < -2 / 15x + 0.8.

[0154] Then, in Figs. 13 and 14, when comparing the distributions of the samples with a film state of "◎" and a designability of "○" and the samples with a film state of "○" and a designability of "○", in Fig. 13, it is difficult to distinguish the two samples within a specific numerical range, but in Fig. 14, it was found that they can be distinguished with the straight line of y = -2 / 15x + 0.8 as the boundary.

[0155] Therefore, it was found that by performing color printing on the metallic gloss base so that the arithmetic mean height (Sa) and the transmission density satisfy any of the above relational expressions, a color feeling that can withstand practical use can be imparted to the metallic gloss base while maintaining the metallic feeling of the metallic gloss base.

[0156] The samples of Example 2 were also subjected to the evaluation test in the same manner as in Example 1, and the above test results are summarized in the following table. However, in Example 2, the above sensory test was not performed, but a visual confirmation was made as to whether the samples had a metallic luster (colored metallic luster).

Table 7

[0157] Similar to Example 1, when plotting LogHAZE of each sample of Example 2 against ΔL*, it becomes as shown in Fig. 15. Also, when plotting the transmission density of these samples against Sa, it becomes as shown in Fig. 16.

[0158] In Fig. 15, samples with LogHAZE of 700 or more and ΔL* of 35 or more are indicated by ■, samples with LogHAZE less than 700 and ΔL* less than 35 are indicated by ▲, and samples with ΔL* of 35 or more and LogHAZE less than 700 are indicated by ●. Samples with LogHAZE less than 700 and ΔL* less than 35 (▲) did not have a metallic luster. Samples with LogHAZE of 700 or more and ΔL* of 35 or more (■) and samples with ΔL* of 35 or more and LogHAZE less than 700 (●) had a metallic luster. In particular, samples with ΔL* of 35 or more and LogHAZE less than 700 (●) were found to have an Rspec value of 50 or more and a different metallic feeling (metallic luster) from samples with LogHAZE of 700 or more. Samples with LogHAZE of 700 or more and ΔL* of 35 or more (■) and samples with LogHAZE less than 700 (Rspec value of 50 or more) (●) both had a colored metallic luster, but the former had a rough texture (matte finish) metallic luster and the latter had a smooth texture (mirror finish) metallic luster.

[0159] Two samples in which the color layer was printed under the same ink type and the same printing conditions (e.g., dot size, number of dots, UV irradiation interval, etc.) in Example 1 and Example 2 (the two samples differed in the material of the base (metallic gloss surface) of the color layer CL). When comparing multiple sets of samples with colored metallic gloss, it was found that the samples of Example 2 had significantly increased numerical values for both LogHAZE and ΔL* compared to the samples of Example 1. Also, for C2-1 and PB2-1, which are samples of Example 2 with the same printing conditions as C1-2 and PB1-1 among the samples where both the film state and the design property were × in the sensory test of Example 1, LogHAZE was improved to around 700 and ΔL* was also improved by 40 or more compared to C1-2 and PB1-1 respectively. Therefore, the metallic gloss feeling was improved and the design property was improved. For this reason, when the metallic gloss feeling of the base is high (e.g., when the surface on which the color layer is formed is made of metal like the base material 50), even under printing conditions where colored metallic gloss cannot be obtained when the metallic gloss feeling of the base is low (e.g., when a metallic gloss layer is formed with metallic ink like the base material 10), it was found that a colored metallic gloss feeling can be obtained by the color layer in some cases.

[0160] Also, in FIG. 16, when the arithmetic mean height Sa is x (μm) and the transmission density is y, it was found that for samples (▲) other than those where LogHAZE is less than 700 and ΔL* is less than 35 (i.e., samples (■ and ●) having a metallic luster), x and y satisfy the relational expression y < -1 / 16x + 0.8. This condition is a relaxed condition compared to the case of providing a color layer on a substrate (such as substrate 10) on which a metallic luster layer is formed with metallic ink (see the results of Example 1). That is, when printing a color layer on a substrate (such as substrate 50) whose metallic luster surface material is metal, even when printing under conditions that are more relaxed than the case of printing a color layer on a substrate on which a metallic luster layer is formed with metallic ink (the condition of y < -1 / 16x + 0.8), it was found that a colored metallic luster can be obtained. Further, it was found that the printing conditions for the color layer that can achieve a colored metallic luster may be different between a substrate on which a metallic luster layer is formed with metallic ink and a substrate whose metallic luster surface material is metal.

[0161] (Modified Example) When printing the color layer, for the first region of the metallic substrate, the color layer was printed under the same conditions as the printing conditions for samples (C2-7 to C2-10, B2-1) where Rspec is 50 or more, and for the second region of the substrate, the color layer was printed under the same conditions as the printing conditions for samples (C2-2 to C2-6, PB2-1 to PB2-2) where LogHAZE is 700 or more and ΔL* is 35 or more. In this case, metallic lusters with different textures were obtained in the first region and the second region. For the former color layer, after the ink droplets landed on the substrate, they leveled, and there were almost no irregularities on the color layer, so the color layer was able to express a metallic luster like a mirror surface. On the other hand, for the latter color layer, since irregularities remained after the ink hardened, according to the color layer, a matte metallic luster that appears differently depending on the viewing angle could be expressed. Thus, in this example, metallic lusters with different textures could be obtained.

Explanation of Symbols

[0162] 10 Substrate 11 Sheet 12 Metal tone layer 20, 30, 40 Color layer 50 Substrate 60 Color layer 21, 31, 61 Dots 22 Gap 32, 62 Thin film part 100 Inkjet printer 110 Conveyor mechanism 120 Ink tank 130 Ink supply mechanism 140 Print head 150 Driving mechanism 160 Radiation irradiation unit 170 Control unit 300 Computer 310 Memory unit 320 Control unit 330 Operation unit 340 Display unit G Image G1 First image G2 Second image P, Q, R, S Printed matter PS Printing system

Claims

1. A first step of preparing a substrate having a metallic luster surface with a metallic luster; A second step of printing a color layer on the metallic luster surface by an inkjet method; and the method has the steps, The color layer is formed of a radiation-curable ink by an inkjet method and has dots with gaps therebetween, In the second step, at least a part of the color layer is formed to have a thickness through which light reflected by the metallic luster surface can pass, The second step includes: A second - 1 step of selecting any one of a plurality of prepared printing conditions for printing the color layer for adding color to the metallic luster; A second - 2 step of printing the color layer based on the printing conditions selected in the second - 1 step; and the second step includes the steps, The first step includes a selection step of selecting, as the substrate, either (1) a first substrate including a base member and a metallic luster layer formed of metallic ink on at least a part of the base member and having the metallic luster surface, or (2) a second substrate having a metallic part forming the metallic luster surface, When the first substrate is selected in the selection step, the plurality of printing conditions include conditions for printing a color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = - 0.1067x + 0.8) on a coordinate of the arithmetic mean height x (μm) and the transmission density y measured in a state of being laminated on the metallic luster surface, When the second substrate is selected in the selection step, the plurality of printing conditions include conditions for printing a color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = - 0.0625x + 0.8) on a coordinate of the arithmetic mean height x (μm) and the transmission density y measured in a state of being laminated on the metallic luster surface, A method for producing a laminate.

2. A printing mechanism capable of printing on a metallic luster surface with a metallic luster by a radiation - curable ink by an inkjet method; A printing control unit that controls the printing mechanism and prints a color layer on the metallic luster surface by the printing mechanism; and the printing control unit controls the printing mechanism, The printing control unit prints the color layer so that at least a part of the color layer has a thickness through which light reflected by the metallic luster surface can pass and has dots with gaps therebetween. The printing control unit acquires at least one printing condition from a storage unit that stores a plurality of printing conditions for printing the color layer that adds color to the metallic luster, and prints the color layer based on the acquired at least one printing condition. (1) When the base material provided with the metallic luster surface is a first base material including a base member and a metallic luster layer formed of metallic ink on at least a part of the base member and having the metallic luster surface, the plurality of printing conditions are measured in a state of being laminated on the metallic luster surface, and include conditions for printing a color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.1067x + 0.8) on a coordinate of the arithmetic mean height x (μm) and the transmission density y, or (2) when the base material is a second base material having a metal portion forming the metallic luster surface, the plurality of printing conditions are measured in a state of being laminated on the metallic luster surface, and include conditions for printing a color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.0625x + 0.8) on a coordinate of the arithmetic mean height x (μm) and the transmission density y. Printing system.

3. The printing conditions are editable by a user, and the printing control unit prints the color layer based on the edited printing conditions. The printing system according to claim 2.

4. The plurality of printing conditions are one or more first printing conditions acquired by the printing control unit when the base material is the first base material, and one or more second printing conditions acquired by the printing control unit when the base material is the second base material, and include at least one of the one or more first printing conditions is different from at least one of the one or more second printing conditions. The printing system according to claim 2 or 3.

5. One or more of the first printing conditions include conditions for printing a color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.1067x + 0.8) on a coordinate of the arithmetic mean height x (μm) and the transmission density y, measured in a state of being laminated on the metallic luster surface. One or more of the second printing conditions include printing the color layer having an arithmetic mean height and a transmission density located in a region below a straight line represented as (y = -0.0625x + 0.8) on a coordinate of the arithmetic mean height x (μm) and the transmission density y, measured in a state laminated on the metallic lustrous surface. The printing system according to claim 4.

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