Luminescent image maker

Abstract

To provide a light-emitting image forming body capable of visually perceiving gradation images produced by the emission of multiple colors, and a method for producing such a light-emitting image forming body. [Solution] The light-emitting image forming body (3) comprises a first light-emitting printing layer (31) formed on a substrate (2) with a first light-emitting ink containing a first light-emitting element that emits first visible light, and a second light-emitting printing layer (32) laminated on the first light-emitting printing layer (31) and formed on a second light-emitting ink containing a second light-emitting element. The first light-emitting printing layer (31) has a first grayscale light-emitting pattern (311) in which the light emission intensity of the first light-emitting element is lower than before laser irradiation. The second light-emitting printing layer (32) has a second grayscale light-emitting pattern (321) in which the light emission intensity of the second light-emitting element is lower than before laser irradiation. An luminescent image formed by additive color mixing of the first grayscale light emission of the first grayscale light-emitting pattern (311) emitted by the excitation light and the second grayscale light emission of the second grayscale light-emitting pattern (321) emitted by the excitation light is visible.

Description

Technical Field

[0001] The present invention is a light-emitting image forming body that irradiates a printing layer containing a phosphor with a laser to form a gradation image having light emission intensities of strong and weak due to deactivation of the phosphor.

Background Art

[0002] For anti-counterfeiting printed matter such as banknotes, passports, stamps, postage stamps, securities, identity certificates, various tickets, security labels, etc., it is required to impart advanced anti-counterfeiting technologies and authenticity discrimination technologies.

[0003] In recent years, in security products such as securities including banknotes at home and abroad, light-emitting materials are widely used as anti-counterfeiting measures, and a technique for confirming whether it is a counterfeit by confirming light emission by using a simple discriminator such as an ultraviolet lamp or a UV-LED is generally known.

[0004] As an example, the present applicant has filed an application for a special light-emitting printed matter in which a first printing layer formed of a phosphorescent phosphor that emits a first fluorescent emission color and a second light-emitting printing layer having a second fluorescent emission color are laminated on at least a part of a base material, and an image by additive color mixing is visible (for example, see Patent Document 1).

[0005] Also, there is disclosed a printed matter in which a plurality of printing regions or ruled lines having different arrangement directions of ten thousand lines constituting a visible image are formed by different fluorescent light-emitting inks, and a latent image is formed by color mixing of fluorescent light emission (for example, see Patent Document 2).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

[0007] However, the technologies described in Patent Documents 1 and 2 use multiple individual phosphors to form a fluorescent image that is visible when the colors are mixed, making it difficult to provide a tonal image using multi-color emission.

[0008] Therefore, there was a demand for printed materials that could produce tonal images through multi-color emission. [Means for solving the problem]

[0009] The present invention relates to an emissive image forming body having a first emissive printing layer containing a first emissive that emits first visible light when excited by a predetermined wavelength on at least a portion of the substrate, and a first emissive image layer having a second emissive printing layer laminated on the first emissive printing layer and formed by a second emissive ink containing a second emissive that emits second visible light when excited by a predetermined wavelength, wherein the first emissive image layer i) has at least a portion of a first grayscale emissive pattern that emits first grayscale emissive with a lower emissive intensity than first visible light, and an emissive image formed by additive color mixing of the first grayscale emissive pattern and second visible light is visible, or ii) The second light-emitting printing layer has at least a portion of a second-tone light-emitting pattern with a light intensity lower than the second visible light, and the light-emitting image formed by additive color mixing of the second-tone light-emitting pattern and the first visible light is visible, or iii) The first light-emitting printing layer has at least a portion of a first-tone light-emitting pattern that produces a first-tone light-emitting with a light intensity lower than the first visible light, and the second light-emitting printing layer has at least a portion of a second-tone light-emitting pattern with a light intensity lower than the second visible light, and the light-emitting image formed by additive color mixing of the first-tone light-emitting pattern and the second-tone light-emitting pattern is visible.

[0010] The present invention relates to an emissive image forming body characterized in that a first emissive image layer is laminated with a third emissive printing layer formed of a third emissive ink containing a third emissive that emits third visible light when excited by excitation light, the third emissive printing layer has at least a portion of a third grayscale emissive pattern that emits third grayscale emissive with a lower emissive intensity than third visible light, and an image formed by additive color mixing with the emissive image is visible.

[0011] The present invention is an luminescent image forming body characterized in that the first luminescent image layer is further laminated with a third color layer formed by an ink containing a third colorant that subtractively mixes the mixed light of the first visible light and the second visible light.

[0012] The present invention relates to an emissive image forming body having a second emissive image layer formed on a substrate, the second emissive image layer being made of an emissive ink containing a first emissive that emits first visible light when excited by a predetermined wavelength of light, and a second emissive that emits second visible light when excited by light, wherein the second emissive image layer has, in part, a first grayscale emissive pattern that emits first grayscale emissive with a lower emissive intensity than the first visible light, and the emissive image formed by additive color mixing of the first grayscale emissive pattern and the second visible light is visible, or, (v) second visible The light-emitting image forming body is characterized by having at least a portion of a second-tone light emission pattern with a light emission intensity lower than the visible light emission, and by the additive color mixing of the second-tone light emission pattern and the first visible light emission being visible, or Vi) having at least a portion of a first-tone light emission pattern that produces a first-tone light emission with a light emission intensity lower than the first visible light emission, and a second-tone light emission pattern with a light emission intensity lower than the second visible light emission, and by the additive color mixing of the first-tone light emission pattern and the second-tone light emission pattern being visible.

[0013] The present invention relates to an emissive image forming body characterized in that the second emissive image layer is formed from an emissive ink containing a third emissive that emits a third visible emission when excited by excitation light, and has at least a portion of a third grayscale emission pattern that emits a third grayscale emission with a lower emission intensity than the third visible emission, and an image obtained by additive color mixing of the emissive image and the third grayscale emission pattern is visible.

[0014] The present invention relates to a light-emitting image forming body characterized in that the light-emitting ink contains a third colorant that subtractively mixes the mixed light of a first visible light emission and a second visible light emission.

[0015] The present invention relates to an luminescent image forming body characterized in that the substrate contains a third colorant that subtractively mixes the mixed light of a first visible emission and a second visible emission.

[0016] The present invention relates to a light-emitting image layer forming step and a method for producing a light-emitting image formed body by irradiating the light-emitting image layer with a laser after the light-emitting image layer forming step, wherein the light-emitting image layer forming step is to form a first light-emitting image layer on at least a part of a substrate by laminating a first light-emitting printing layer formed with a first light-emitting ink containing a first light-emitting element and a second light-emitting printing layer formed with a second light-emitting ink containing a second light-emitting element, or to form a second light-emitting image layer on at least a part of a substrate with a light-emitting ink containing a first light-emitting element and a second light-emitting element, and the laser irradiation step is to vii) irradiate the first light-emitting image layer or the second light-emitting image layer with a first laser to deactivate the second light-emitting element and form a second grayscale light emission pattern on at least a part of the second light-emitting printing layer or the second light-emitting image layer that produces a second grayscale light emission with a light emission intensity lower than the light emission intensity of the second visible light, or viii) irradiate the first light-emitting image layer or the second light-emitting image layer with a second laser to deactivate the first light-emitting element and form a second grayscale light emission pattern on at least a part of the second light-emitting printing layer or iX) A method for producing an emitting image forming body, characterized by the steps of: iX) forming a first-tone emission pattern on at least a part of the second emitting image layer that produces a first-tone emission with an emission intensity lower than the emission intensity of the first visible emission; iX) irradiating the first emitting image layer or the second emitting image layer with a first laser to deactivate the second light emitter and forming a second-tone emission pattern on at least a part of the second emitting print layer or the second emitting image layer that produces a second-tone emission with an emission intensity lower than the emission intensity of the second visible emission; and iX) irradiating the first emitting image layer or the second emitting image layer with a second laser to deactivate the first light emitter and the second light emitter and forming a second-tone emission pattern on at least a part of the second emitting print layer or the second emitting image layer that has an emission intensity lower than the second-tone emission pattern formed by the first laser, without overlapping, and forming a first-tone emission pattern on at least a part of the first emitting print layer or the second emitting image layer that produces a first-tone emission with an emission intensity lower than the emission intensity of the first visible emission.

[0017] The present invention relates to a method for producing an emitting image formed body comprising an emitting image layer formation step of forming a second emitting image layer and a laser irradiation step of irradiating the second emitting image layer with a laser after the emitting image layer formation step, wherein the emitting image layer formation step involves forming a second emitting image layer on at least a portion of a substrate using an emitting ink containing a first emitting element that emits first visible light when excited by excitation light of a predetermined wavelength and a second emitting element that emits second visible light when excited by excitation light of a predetermined wavelength, and the laser irradiation step involves X) irradiating the second emitting image layer with a first laser to deactivate the second emitting element and forming a second grayscale emission pattern on at least a portion of the second emitting image layer that emits second grayscale emission with an emission intensity lower than that of second visible light, or Xi) irradiating the second emitting image layer with a second laser to deactivate the first emitting element and forming a first grayscale emission pattern on at least a portion of the second emitting image layer The method for producing an emitting image forming body is characterized by forming a first-tone emission pattern that produces a first-tone emission with an emission intensity lower than that of visible light, or (Xii) irradiating the second emitting image layer with a first laser to deactivate the second light emitter and forming a second-tone emission pattern that produces a second-tone emission with an emission intensity lower than that of second visible light in at least a part of the second emitting image layer, irradiating the second emitting image layer with a second laser to deactivate the first and second light emitters and further forming an emission pattern with an emission intensity lower than that of the second-tone emission pattern in at least a part of the second emitting image layer at a position that does not overlap with the second-tone emission pattern formed by the first laser, thereby forming a first-tone emission pattern that produces a first-tone emission with an emission intensity lower than that of first visible light in at least a part of the second emitting image layer. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a light-emitting image forming body that allows for the visualization of a gradation image produced by the emission of multiple colors. [Brief explanation of the drawing]

[0019] [Figure 1] This is a schematic diagram representing a light-emitting image forming body according to the first embodiment of the present invention. [Figure 2] This is a cross-sectional view at cross-section AA shown in Figure 1. [Figure 3] It is a schematic diagram showing the first light-emitting printing layer of the first embodiment. [Figure 4] It is a schematic diagram showing the second light-emitting printing layer of the first embodiment. [Figure 5] It is a schematic diagram showing a light-emitting image by additive color mixing in the first embodiment. [Figure 6] It is a schematic diagram showing a light-emitting image forming body according to a modification of the first embodiment. [Figure 7] It is a schematic diagram showing a light-emitting image forming body according to the second embodiment of the present invention. [Figure 8] It is a cross-sectional view taken along the cutting plane B-B shown in FIG. 7. [Figure 9] It is a schematic diagram showing the first gradation light-emitting pattern of the second embodiment. [Figure 10] It is a schematic diagram showing the second gradation light-emitting pattern of the second embodiment. [Figure 11] It is a flowchart showing a method for manufacturing a light-emitting image forming body according to the first embodiment of the present invention. [Figure 12] It is a schematic diagram for explaining the processing of image data related to a light-emitting image. [Figure 13] It is a flowchart showing a method for manufacturing a light-emitting image forming body according to the second embodiment of the present invention. [Figure 14] It is a table for explaining an example of the result of studies conducted by the present inventor.

Embodiments for Carrying Out the Invention

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are preferred specific examples of the present invention, and thus are technically preferably subject to various limitations. However, the scope of the present invention is not limited to these aspects unless there is a description to specifically limit the present invention in the following description. Also, in each drawing, the same reference numerals are assigned to the same components, and detailed descriptions thereof are appropriately omitted.

[0021] (First Embodiment) As shown in Figures 1 and 2, the light-emitting image forming body (1) according to the first embodiment has a first light-emitting image layer (3) formed on a substrate (2). When viewed in the direction of arrow A1 shown in Figure 2, a light-emitting image (4) formed by additive color mixing can be seen using an ultraviolet lamp or UV-LED. The principle of additive color mixing is a principle that is generally known as the additive color mixing of R (red), G (green), and B (blue) light emission. The first light-emitting image layer (3) shown in Figures 1 and 2 is formed on a part of the substrate (2), but it may be formed on the entire substrate (2).

[0022] In this description of the embodiment, a face image is given as an example of the illuminated image (4). However, the illuminated image (4) is not limited to a face image, and may be, for example, a landscape image. This is also true in other embodiments described later.

[0023] As shown in Figure 2, the first light-emitting image layer (3) comprises a first grayscale light-emitting pattern (311) formed on the first light-emitting printing layer (31) and a second grayscale light-emitting pattern (321) formed on the second light-emitting printing layer (32) at a position overlapping with the first grayscale light-emitting pattern (311).

[0024] Furthermore, in Figure 2, the second tone emission pattern (321) is superimposed on the entire first tone emission pattern (311), but it is sufficient for at least a portion of the first tone emission pattern (311) and the second tone emission pattern (321) to be superimposed. By superimposing the first tone emission pattern (311) and the second tone emission pattern (321), the emission image (4) resulting from the mixing of the first tone emission and the second tone emission, as described later, can be visually observed.

[0025] The first light-emitting printing layer (31) is formed on the substrate (2) by applying the first light-emitting ink to the upper surface of the substrate (2). The first light-emitting ink contains a first light-emitting element. The first light-emitting element emits first visible light when excited by excitation light of a predetermined wavelength. Examples of excitation light of a predetermined wavelength include ultraviolet light (UV-C) with a wavelength of 254 nanometers (nm) and ultraviolet light (UV-B) with a wavelength of 302 nm. However, the wavelength of the excitation light is not limited to 254 nm and 302 nm, and may also be ultraviolet light (UV-A) with a wavelength of 365 nm.

[0026] The method for applying the first light-emitting ink to the upper surface of the substrate (2) is not particularly limited, and any known method for applying the first light-emitting ink, such as offset printing, letterpress printing, flexographic printing, screen printing, gravure printing, intaglio printing, and inkjet printing, can be used.

[0027] The first light-emitting element is not particularly limited, and any known inorganic or organic luminescent pigment can be used. Here, an example using an inorganic red luminescent pigment will be described. When the first light-emitting element contains a red luminescent pigment, the first light-emitting element emits red light as first visible light when excited by a predetermined wavelength of light.

[0028] As shown in Figure 2, the second light-emitting printing layer (32) is laminated on the first light-emitting printing layer (31) by applying the second light-emitting ink to the upper surface of the first light-emitting printing layer (31), but the first light-emitting printing layer (31) may be laminated on the second light-emitting printing layer (32). The second light-emitting printing layer (32) may be formed over the entire substrate (2) via the first light-emitting printing layer (31), similar to the first light-emitting printing layer (31). The second light-emitting ink contains a second light-emitting element. The second light-emitting element emits a second visible light of a different color from the first visible light emission when excited by a predetermined wavelength of light. The predetermined wavelength of light-emitting element is as described above.

[0029] The second light-emitting element is not particularly limited, and any known inorganic or organic luminescent pigment can be used. Here, an example using an organic green luminescent pigment will be described. When the second light-emitting element contains a green luminescent pigment, the second light-emitting element will emit green light as second visible light when excited by light of a predetermined wavelength.

[0030] The first and second light-emitting elements are not limited to the examples described above. For example, the first light-emitting element of the first light-emitting printing layer (31) may contain a green light-emitting pigment, and the second light-emitting element of the second light-emitting printing layer (32) may contain a red light-emitting pigment. Furthermore, each of the first and second light-emitting elements may contain a light-emitting pigment that emits a color other than red or green.

[0031] The substrate (2) is not particularly limited, as long as it does not affect the emission of light from the first and second light emitters. Examples of substrates (2) include known paper, plastic, film, and cloth. Examples of substrates (2) being paper include fine paper, medium-quality paper, lightly coated paper, coated paper, art paper, cast-coated paper, kraft paper, and synthetic paper.

[0032] As shown in Figures 2 and 3, the first light-emitting printed layer (31) has a first-tone light-emitting pattern (311). The first-tone light-emitting pattern (311) is the portion of the first light-emitting printed layer (31) in which the light emission intensity of the first light-emitting element has decreased compared to before laser irradiation. In other words, the first-tone light-emitting pattern (311) is the portion of the first light-emitting layer (31) in which at least a part of the first light-emitting element has been deactivated, and is formed by reducing the light emission intensity of the first light-emitting element compared to before laser irradiation by laser irradiation. An example of a laser used to form the first-tone light-emitting pattern (311) is a UV laser with a wavelength of 355 nm. However, the wavelength of the laser used to form the first-tone light-emitting pattern (311) is not limited to 355 nm.

[0033] As shown in Figure 3, the first-tone emission pattern (311) has a first tone that shows a change in the intensity of the first visible emission. The first tone emission of the first-tone emission pattern (311) is formed by adjusting the irradiation conditions (e.g., frequency) of the laser used to form the first-tone emission pattern (311) and adjusting the degree of deactivation of the first light emitter. In other words, the part of the first light emitter that is completely deactivated will not emit the first visible emission even when irradiated with excitation light of a predetermined wavelength. On the other hand, the part of the first light emitter that is incompletely deactivated (i.e., a partially deactivated part) will emit the first visible emission with a lower emission intensity than before laser irradiation when irradiated with excitation light of a predetermined wavelength. Thus, the first tone emission of the first-tone emission pattern (311) is formed by adjusting the intensity of the red emission by adjusting the laser irradiation conditions according to the color of the face, which is the emission image (4).

[0034] As shown in Figures 2 and 4, the second light-emitting printed layer (32) has a second grayscale light-emitting pattern (321). The second grayscale light-emitting pattern (321) is the portion of the second light-emitting printed layer (32) in which the light emission intensity of the second light-emitting element has decreased compared to before laser irradiation. In other words, the second grayscale light-emitting pattern (321) is the portion of the second light-emitting layer (32) in which at least a part of the second light-emitting element has been deactivated, and is formed by reducing the light emission intensity of the second light-emitting element compared to before laser irradiation by laser irradiation. The laser used to form the second grayscale light-emitting pattern (321) is the same as the laser used to form the first grayscale light-emitting pattern (311).

[0035] As shown in Figure 4, the second-tone emission pattern (321) has a second-tone emission that shows a change in the intensity of the second visible emission. The second-tone emission of the second-tone emission pattern (321) is formed by adjusting the irradiation conditions (e.g., frequency, etc.) of the laser used to form the second-tone emission pattern (321) and adjusting the degree of deactivation of the second light emitter. In other words, the part of the second light emitter that is completely deactivated will not emit second visible emission even when irradiated with excitation light of a predetermined wavelength. On the other hand, the part of the second light emitter that is incompletely deactivated (i.e., a partially deactivated part) will emit second visible emission with a lower emission intensity than before laser irradiation when irradiated with excitation light of a predetermined wavelength. Thus, the second-tone emission of the second-tone emission pattern (321) is formed by adjusting the intensity of the green emission by adjusting the laser irradiation conditions according to the color of the face, which is the emission image (4). The first-tone emission pattern (311) shown in Figure 3 and the second-tone emission pattern (321) shown in Figure 4 are composed of a collection of dots and images where the light-emitting material has been deactivated by laser irradiation. As mentioned above, the first-tone emission pattern (311) shown in Figure 3 and the second-tone emission pattern (321) shown in Figure 4 are superimposed, but the images, dots, and other elements that constitute the first-tone emission pattern (311) and the second-tone emission pattern (321) shown in Figure 4, which are formed by laser irradiation, are formed at different positions.

[0036] The light resistance of the first light emitter to a laser is different from that of the second light emitter. For example, if the first light emitter contains an inorganic red light-emitting pigment and the second light emitter contains an organic green light-emitting pigment, the light resistance of the first light emitter to a laser is higher than that of the second light emitter. For example, when a laser is irradiated under predetermined irradiation conditions, the first light emitter hardly absorbs the laser, while the second light emitter absorbs it. This makes it possible to make the degree of deactivation of the first light emitter and the degree of deactivation of the second light emitter different, even when the laser is irradiated under predetermined irradiation conditions (i.e., the same irradiation conditions). Alternatively, by making the light resistance of the second light emitter to a laser higher than that of the first light emitter, when the laser is irradiated under predetermined irradiation conditions, the second light emitter hardly absorbs the laser, while the first light emitter absorbs it, thereby making the degree of deactivation of the first light emitter and the second light emitter different.

[0037] In this way, by adjusting the laser irradiation conditions, a first-tone emission showing a change in the intensity of the first visible emission can be formed in the first-tone emission pattern (311), and a second-tone emission showing a change in the intensity of the second visible emission can be formed in the second-tone emission pattern (321). The laser irradiation timing when forming the first-tone emission pattern (311) may be different from the laser irradiation timing when forming the second-tone emission pattern (321), or it may be the same as the laser irradiation timing when forming the second-tone emission pattern (321). That is, the first-tone emission pattern (311) and the second-tone emission pattern (321) may be formed by multiple (for example, two) laser irradiations, or they may be formed by a single laser irradiation.

[0038] When the light-emitting image forming body (1) according to this embodiment is viewed from the direction of arrow A1 shown in Figure 2, as shown in Figure 5, a light-emitting image (4) can be seen obtained by additive color mixing of the first tone emission of the first tone emission pattern (311) emitted by the excitation light and the second tone emission of the second tone emission of the second tone emission pattern (321) emitted by the excitation light. Therefore, according to the light-emitting image forming body (1) according to this embodiment, the light-emitting image (4) can be seen as a tone image obtained by the emission of multiple colors, that is, as a color tone image.

[0039] Furthermore, since the first light-emitting printing layer (31) has a first-grade emission pattern (311) in which the emission intensity of the first light-emitting element is lower than before laser irradiation, and the second light-emitting printing layer (32) has a second-grade emission pattern (321) in which the emission intensity of the second light-emitting element is lower than before laser irradiation, compared to the case where multiple color images are printed together to form a color emission image, the misalignment of multiple color emission can be suppressed, and a clear emission image (4) can be viewed.

[0040] Furthermore, according to the light-emitting image forming body (1) of this embodiment, a light-emitting image (4) showing variations in the intensity of multiple colors is formed. This makes it possible to improve the reproducibility of light-emitting images (4), such as facial images or landscape images, in security products such as passports and cards.

[0041] Next, a modified example of the first embodiment will be described with reference to the drawings. Note that if the components of the light-emitting image forming body (1') according to the modified example of the first embodiment are the same as the components of the light-emitting image forming body (1) according to the present embodiment described above with reference to Figures 1 to 4, redundant explanations will be omitted as appropriate, and the differences will be the focus of the description below.

[0042] As shown in Figure 6, the light-emitting image forming body (1') according to this modified example is formed by laminating a third light-emitting print layer (33) on top of a first light-emitting print layer (31) and a second light-emitting print layer (32). In other words, compared to the light-emitting image forming body (3) described above with respect to Figures 1 to 4, the light-emitting image forming body (1') according to this modified example further includes a third light-emitting print layer (33). In this respect, the light-emitting image forming body (1') according to this modified example differs from the light-emitting image forming body (3) described above with respect to Figures 1 to 4.

[0043] The third light-emitting printing layer (33) is laminated on the second light-emitting printing layer (32) by applying the third light-emitting ink to the upper surface of the second light-emitting printing layer (32). However, the lamination order is not limited to this, and it may also be laminated on the lower surface of the first light-emitting layer (31) or between the first light-emitting printing layer (31) and the second light-emitting printing layer (32). The third light-emitting printing layer (33) may be formed over the entire substrate (2) via the first light-emitting printing layer (31) and the second light-emitting printing layer (32), similar to the first light-emitting printing layer (31). The third light-emitting ink contains a third light-emitting element. The third light-emitting element emits a third visible light of a different color from the first visible light and the second visible light when excited by excitation light of a predetermined wavelength. The excitation light of a predetermined wavelength is as described above with respect to Figures 1 to 4.

[0044] The third light-emitting element is not particularly limited, and any known inorganic or organic luminescent pigment can be used. Here, an example using a purple luminescent pigment or a blue luminescent pigment will be described. When the third light-emitting element contains a purple luminescent pigment or a blue luminescent pigment, the third light-emitting element will emit purple or blue light as third visible light when excited by a predetermined wavelength of light.

[0045] As shown in Figure 6, the third light-emitting printing layer (33) has a third grayscale light-emitting pattern (331). The third grayscale light-emitting pattern (331) is the portion of the third light-emitting printing layer (33) where the light emission intensity of the third light-emitting element has decreased compared to before laser irradiation. In other words, the third grayscale light-emitting pattern (331) is the portion of the third light-emitting printing layer (33) where at least a part of the third light-emitting element has been deactivated, and is formed by reducing the light emission intensity of the third light-emitting element compared to before laser irradiation by laser irradiation. The laser used to form the third grayscale light-emitting pattern (331) is the same as the laser used to form the first grayscale light-emitting pattern (311) and the second grayscale light-emitting pattern (321). Note that the third grayscale light-emitting pattern (331) only needs to be superimposed on at least a portion of the first grayscale light-emitting pattern and the second grayscale light-emitting pattern. By superimposing the first-level light emission pattern (311), the second-level light emission pattern (321), and the third-level light emission pattern (331), it is possible to produce graded light emission by mixing the first-level light emission, the second-level light emission, and the third-level light emission.

[0046] The third-tone emission pattern (331) has a third-tone emission that shows a change in the intensity of third-visible light emission. The third-tone emission of the third-tone emission pattern (331) is formed by adjusting the irradiation conditions (e.g., frequency, etc.) of the laser used to form the third-tone emission pattern (331) and adjusting the degree of deactivation of the third light emitter. In other words, a portion of the third light emitter that is completely deactivated will not emit third-visible light even when irradiated with excitation light of a predetermined wavelength. On the other hand, a portion of the third light emitter that is incompletely deactivated (i.e., a partially deactivated portion) will emit third-visible light when irradiated with excitation light of a predetermined wavelength, with a emission intensity lower than before laser irradiation. Thus, the third-tone emission of the third-tone emission pattern (331) is formed by adjusting the intensity of blue or purple light emission by adjusting the laser irradiation conditions according to the color of the face, which is the emission image (4).

[0047] The light resistance of the third light emitter to a laser differs from that of the first and second light emitters. For example, if the first light emitter contains a red light-emitting pigment, the second light emitter contains a green light-emitting pigment, and the third light emitter contains an organic purple light-emitting pigment or an organic blue light-emitting pigment, the light resistance of the third light emitter to a laser will be lower than that of the first and second light emitters. For example, when a laser is irradiated under predetermined irradiation conditions, the first and second light emitters will hardly absorb the laser, while the third light emitter will absorb it. This makes it possible to make the degree of deactivation of the third light emitter and the degree of deactivation of the first and second light emitters different, even when the laser is irradiated under predetermined irradiation conditions (i.e., the same irradiation conditions).

[0048] In this way, by adjusting the laser irradiation conditions, a first-level emission pattern (311) showing a change in the intensity of first visible light can be formed, a second-level emission pattern (321) showing a change in the intensity of second visible light can be formed, and a third-level emission pattern (331) showing a change in the intensity of third visible light can be formed. The laser irradiation timing when forming the third-level emission pattern (331) may be different from the laser irradiation timing when forming the first-level emission pattern (311) and the second-level emission pattern (321), or it may be the same as the laser irradiation timing when forming the first-level emission pattern (311) and the second-level emission pattern (321). That is, the first-level emission pattern (311), the second-level emission pattern (321), and the third-level emission pattern (331) may be formed by multiple (for example, three) laser irradiations, or by a single laser irradiation.

[0049] When the modified light-emitting image forming body (1') according to the first embodiment is viewed from the direction of arrow A2 shown in Figure 6, the light-emitting image (4) formed by additive color mixing of the first tone emission of the first tone emission pattern (311) emitted by the excitation light, the second tone emission of the second tone emission of the second tone emission pattern (321) emitted by the excitation light, and the third tone emission of the third tone emission of the third tone emission pattern (331) can be observed. Therefore, with the light-emitting image forming body (1') according to this modified embodiment, the hue (i.e., emission color) of the light-emitting image (4) can be increased compared to the light-emitting image forming body (3) described above with respect to Figures 1 to 4, and the reproducibility of light-emitting images (4) such as face images and landscape images can be improved. Furthermore, the same effects as those of the light-emitting image forming body (1) according to the embodiment described above can be obtained with respect to Figures 1 to 4.

[0050] In addition, while a modified version of the first embodiment has a third light-emitting printing layer (33) laminated using a third light-emitting element, a substrate (2) containing a third colorant (for example, a blue or purple dye or pigment) that subtractively mixes the mixed light of the first visible light and the second visible light may be used instead of the third light-emitting printing layer (33).

[0051] Alternatively, a color layer formed with a third colorant (e.g., a blue or purple dye or pigment) that subtractively mixes the mixed light of the first visible light and the second visible light may be laminated. For example, if the first visible light is red and the second visible light is green light, a purple dye or pigment can be used to suppress the yellowish tint of the mixed light. In addition, although the light-emitting image forming body (1) of the first embodiment forms a light-emitting image (4) with a first grayscale light-emitting pattern (311) and a second grayscale light-emitting pattern (321), it is sufficient to have at least one of the first grayscale light-emitting pattern (311) or the second grayscale light-emitting pattern (321).

[0052] For example, by forming a second grayscale emission pattern (321) on a first light-emitting printing layer (31) formed with a first light-emitting element that has high light resistance to lasers, without forming a first grayscale emission pattern (311), and instead deactivating only the second light-emitting element that has lower light resistance to lasers than the first light-emitting element, it is possible to form a light-emitting image (4) that exhibits a grayscale emission image consisting of first visible light emission and second grayscale emission. Alternatively, by forming a first grayscale emission pattern (311) on a second light-emitting printing layer (32) formed with a second light-emitting element that has high light resistance to lasers, without forming a second grayscale emission pattern (321), and instead deactivating only the first light-emitting element that has lower light resistance to lasers than the second light-emitting element, it is possible to form a grayscale emission image consisting of second visible light emission and first grayscale emission. Therefore, in either configuration, a grayscale emission image due to multicolor emission is formed. Next, an example of a light-emitting element is given.

[0053] The red fluorescent emitter is not particularly limited as long as it emits red fluorescence, for example, perylene derivatives, europium complexes, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, porphyrin derivatives, Nile Red, 2-(1,1-dimethylethyl)-6-(2-(2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H-benzo(ij)quinoridine-9-yl)ethenyl)-4H-pyran-4H-ylidene)propanedinitrile (DCJTB), 4-(dicyanomethylene)-2-methyl- Examples include 6-(p-dimethylaminostyryl)-4H-pyran (DCM), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-(1-cyanobinylenephenylene)], poly[{9,9-dihexyl-2,7-bis(1-cyanobinylene)fluorenylene}ortho-co-{2,5-bis(N,N'-diphenylamino)-1,4-phenylene}], and poly[{2-methoxy-5-(2-ethylhexyloxy)-1,4-(1-cyanobinylenephenylene)}-co-{2,5-bis(N,N'-diphenylamino)-1,4-phenylene}].

[0054] The green fluorescent emitter is not particularly limited as long as it emits green fluorescence, for example, an emission wavelength of 520-545 nm. Examples include coumarin derivatives, quinacridone and its derivatives, 9,10-bis[(9-ethyl-3-carbazole)-vinylenyl]-anthracene, poly(9,9-dihexyl-2,7-vinylenefluorenylene), poly[(9,9-dioctylfluorene-2,7-diyl)-co-(1,4-diphenylene-vinylene-2-methoxy-5-{2-ethylhexyloxy}benzene)], poly[(9,9-dioctyl-2,7-divinylenefluorenylene)-ortho-co-(2-methoxy-5-(2-ethoxylhexyloxy)-1,4-phenylene)], and poly[(9,9-dioctylfluorene-2,7-diyl)-ortho-co-(1,4-benzo-{2,1',3}-thiadiazole)](F8BT).

[0055] The blue fluorescent emitter is not particularly limited as long as it emits blue fluorescence, for example, distyryldiamine compounds such as distyrylamine derivatives, fluorantene derivatives, pyrene derivatives, perylene and perylene derivatives, anthracene derivatives, benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, chrysene derivatives, phenanthrene derivatives, distyrylbenzene derivatives, tetraphenylbutadiene, 4,4'-bis(9-ethyl-3-carbazovinylene)-1,1'-biphenyl (BCzVBi), poly[( Examples include 9,9-dioctylfluorene-2,7-diyl)-co-(2,5-dimethoxybenzene-1,4-diyl)], poly[(9,9-dihexyloxyfluorene-2,7-diyl)-ortho-co-(2-methoxy-5-{2-ethoxyhexyloxy}phenylene-1,4-diyl)], poly[(9,9-dioctylfluorene-2,7-diyl)-co-(ethylnylbenzene)], and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(N,N'-diphenyl)-N,N'-di(para-butylphenyl)-1,4-diaminobenzene]).

[0056] (Second Embodiment) Next, a second embodiment of the present invention will be described with reference to the drawings. If the components of the light-emitting image forming body (1'') according to the second embodiment are the same as the components of the light-emitting image forming body 1 according to the first embodiment described above with respect to Figures 1 to 4, redundant explanations will be omitted as appropriate, and the differences will be explained below.

[0057] As shown in Figures 7 and 8, the light-emitting image forming body (1'') according to the second embodiment comprises a second light-emitting image layer (34) formed on a substrate (2), and when viewed using an ultraviolet lamp or UV-LED from the direction of arrow A3 shown in Figure 8, the light-emitting image (4) produced by additive color mixing is visible.

[0058] With respect to Figures 1 to 4, the light-emitting image forming body (1) according to the first embodiment described above has a laminated structure of a first light-emitting printing layer (31) and a second light-emitting printing layer (32), while the light-emitting image forming body (1'') according to the second embodiment has a single-layer structure of a second light-emitting image layer (34). In this respect, the light-emitting image forming body (1'') according to the second embodiment differs from the light-emitting image forming body (1) according to the first embodiment.

[0059] As shown in Figure 8, the second light-emitting image layer (34) is formed on the substrate (2) by applying light-emitting ink to the upper surface of the substrate (2). In the light-emitting image forming body (1'') shown in Figures 7 and 8, the second light-emitting image layer (34) is formed on a part of the substrate (2). However, the second light-emitting image layer (34) may be formed on the entire substrate (2).

[0060] The luminescent ink contains a first light-emitting element and a second light-emitting element. That is, the luminescent ink is formed by blending the first light-emitting element and the second light-emitting element in a predetermined ratio.

[0061] The first light emitter emits a first visible emission when excited by a predetermined wavelength of light. The second light emitter emits a second visible emission when excited by a predetermined wavelength of light. Examples of the first and second light emitters are as described above with respect to Figures 1 to 4. The predetermined wavelengths of the excitation light are also as described above with respect to Figures 1 to 4.

[0062] As shown in Figures 8 and 9, the second light-emitting image layer (34) has a first-tone light-emitting pattern (341). The first-tone light-emitting pattern (341) is the portion of the second light-emitting image layer (34) in which the light emission intensity of the first light-emitting element has decreased compared to before laser irradiation. In other words, the first-tone light-emitting pattern (341) is the portion of the second light-emitting image layer (34) in which at least a part of the first light-emitting element has been deactivated, and is formed by reducing the light emission intensity of the first light-emitting element compared to before laser irradiation by laser irradiation. The laser used to form the first-tone light-emitting pattern (341) is the same as the laser used to form the first-tone light-emitting pattern (311) described above with respect to Figures 1 to 4.

[0063] As shown in Figure 9, the first grayscale emission pattern (341) has a first grayscale emission that shows a change in the intensity of the first visible light emission. The method for forming the first grayscale emission of the first grayscale emission pattern (341) is the same as the method for forming the first grayscale emission of the first grayscale emission pattern (311) described above with respect to Figures 1 to 4.

[0064] As shown in Figures 8 and 10, the second light-emitting image layer (34) has a second grayscale light-emitting pattern (342). The second grayscale light-emitting pattern (342) is the portion of the second light-emitting image layer (34) in which the light emission intensity of the second light-emitting element has decreased compared to before laser irradiation. In other words, the second grayscale light-emitting pattern (342) is the portion of the second light-emitting image layer (34) in which at least a part of the second light-emitting element has been deactivated, and is formed by reducing the light emission intensity of the second light-emitting element compared to before laser irradiation by laser irradiation. The laser used to form the second grayscale light-emitting pattern (342) is the same as the laser used to form the first grayscale light-emitting pattern (311) described above with respect to Figures 1 to 4.

[0065] As shown in Figure 10, the second-tone emission pattern (342) has a second-tone emission that shows a change in the intensity of the second visible light emission. The method for forming the second-tone emission of the second-tone emission pattern (342) is the same as the method for forming the second-tone emission of the second-tone emission pattern (321) described above with respect to Figures 1 to 4.

[0066] The light resistance of the first and second light emitters to the laser is as described above with respect to Figures 1 to 4. Therefore, by adjusting the laser irradiation conditions, a first-tone emission showing a change in the intensity of the first visible emission can be formed as the first-tone emission pattern (341), and a second-tone emission showing a change in the intensity of the second visible emission can be formed as the second-tone emission pattern (342). The laser irradiation timing when forming the first-tone emission pattern (341) may be different from the laser irradiation timing when forming the second-tone emission pattern (342), or it may be the same as the laser irradiation timing when forming the second-tone emission pattern (342). In other words, the first-tone emission pattern (341) and the second-tone emission pattern (342) may be formed by multiple (for example, two) laser irradiations, or by a single laser irradiation.

[0067] When the light-emitting image forming body (1'') according to this embodiment is viewed from the direction of arrow A3 shown in Figure 8, as shown in Figure 7, the light-emitting image (4) formed by additive color mixing of the first tone emission of the first tone emission pattern (341) emitted by the excitation light and the second tone emission of the second tone emission of the second tone emission pattern (342) emitted by the excitation light can be seen. Therefore, according to the light-emitting image forming body (1'') according to this embodiment, the light-emitting image (4) can be seen as a tone image formed by the emission of multiple colors, that is, as a color tone image. Furthermore, since the light-emitting image forming body (1'') according to this embodiment is formed from a single layer of light-emitting ink, the number of manufacturing steps can be reduced and the manufacturing process can be simplified. Note that the first tone emission pattern (341) and the second tone emission pattern (342) only need to overlap in some parts.

[0068] With respect to Figure 6, similar to the modified image forming body (1') described above, the luminescent ink may contain a first light emitter, a second light emitter, and a third light emitter. That is, the luminescent ink may further contain a third light emitter. In this case, the luminescent ink is formed by blending the first light emitter, the second light emitter, and the third luminescent ink in predetermined proportions. The blending ratio of the first light emitter, the second light emitter, and the third light emitter is adjusted, for example, so that the luminescent ink emits white light when excited by a predetermined wavelength of light. However, the blending ratio of the first light emitter, the second light emitter, and the third light emitter is not limited to this.

[0069] The third light emitter emits a third visible light when excited by a predetermined wavelength. An example of the third light emitter is as described above with respect to Figure 6. The predetermined wavelength of the excitation light is as described above with respect to Figures 1 to 4.

[0070] When the light-emitting ink contains a first light-emitting element, a second light-emitting element, and a third light-emitting element, when the light-emitting image forming body (1'') according to this embodiment is viewed from the direction of arrow A3 shown in Figure 8, a light-emitting image (4) can be seen obtained by additive color mixing of the first tone emission of the first tone emission pattern (341) emitted by the excitation light, the second tone emission of the second tone emission of the second tone emission pattern (342) emitted by the excitation light, and the third tone emission of the third tone emission of the third tone emission pattern (not shown) emitted by the excitation light. In this case, the same effect as the light-emitting image forming body (1'') according to the modified example described above with respect to Figure 6 can be obtained. Note that the third tone emission pattern only needs to be formed by superimposing at least a part of the first tone emission pattern (341) and the second tone emission pattern (342).

[0071] In addition, although the second embodiment contains a third light-emitting element in the first and second light-emitting elements, a substrate (2) containing a third colorant (for example, a blue or purple dye or pigment) that subtractively mixes the mixed light of the first visible light and the second visible light may be used instead of using the third light-emitting element.

[0072] Alternatively, a third colorant (e.g., a blue or purple dye or pigment) that subtractively mixes the mixed light of the first visible light and the second visible light may be included instead of the third light emitter. For example, if the first visible light is red and the second visible light is green light, a purple dye or pigment can be used to suppress the yellowish tint of the mixed light. In the second embodiment, as in the first embodiment, there is a first-tone emission pattern (341) and a second-tone emission pattern (342), but it is sufficient to have at least one of the first-tone emission pattern (341) and the second-tone emission pattern (342).

[0073] Next, a method for producing a light-emitting image forming body (1) according to the first embodiment of the present invention will be described with reference to the drawings. Figure 11 is a flowchart showing a method for producing a light-emitting image forming body according to the first embodiment of the present invention. Figure 12 is a schematic diagram illustrating the processing of image data related to the light-emitting image (4).

[0074] Figure 11(a) is a flowchart illustrating the basic method for manufacturing an emissive image forming body. In the emissive image layer formation step (S1), a first emissive printing layer (31) is formed on at least a portion of the substrate (2) by laminating a first emissive printing layer (31) with a first emissive ink containing a first emissive and a second emissive printing layer (32) with a second emissive ink containing a second emissive, or a second emissive image layer (34) is formed on at least a portion of the substrate (2) by emissive ink containing both the first and second emissives.

[0075] In the laser irradiation step (S2), for example, after the light-emitting image layer formation step (S1), the first laser is irradiated onto the first light-emitting image layer (3) or the second light-emitting image layer (34) to deactivate the second light-emitting element and form a second grayscale light emission pattern (342) on at least a part of the second light-emitting printing layer (32) or the second light-emitting image layer (34) that produces a second grayscale light emission with a light emission intensity lower than that of the second visible light emission. Furthermore, the laser irradiation step (S2) irradiates the first light-emitting image layer (3) or the second light-emitting image layer (34) with a second laser having an even higher energy intensity than the first laser to deactivate the first and second light-emitting elements, thereby forming a second grayscale light-emitting pattern with a lower light intensity than the second grayscale light-emitting pattern formed by the first laser on at least a part of the second light-emitting printing layer (32) or the second light-emitting image layer (34) without overlapping, and forming a first grayscale light-emitting pattern (311) on at least a part of the first light-emitting printing layer (31) or the second light-emitting image layer (34) that produces a first grayscale light-emitting with a light intensity lower than the light intensity of the first visible light.

[0076] Next, with reference to Figure 11(b), a method for producing a light-emitting image forming body according to the first embodiment of the present invention will be specifically described. First, the image data (41) that will serve as the base image for the light-emitting image (4) (see, for example, Figure 3) is decomposed into color data for each predetermined color system component (S0). For example, as shown in Figure 12, an image processing device is used to decompose the image data (41) into first color data (411) for the reddish-brown component and second color data 412 for the black component. The image processing device is not particularly limited, and known image processing devices can be used, for example, using Adobe® Photoshop®, an image processing software, to create each color data. If the image data (41) of the base image for the light-emitting image (4) has already been decomposed into color data for each predetermined color component, the decomposition process (S0) may be omitted.

[0077] Next, in the light-emitting image layer formation step (S1), a first light-emitting print layer (31) is formed on the substrate (2) using a first light-emitting ink containing a first light-emitting element (S1-1). Specifically, the first light-emitting print layer (31) is formed on the substrate (2) by applying the first light-emitting ink to the upper surface of the substrate (2) (S1-2).

[0078] Next, after the formation of the first light-emitting print layer (31), the second light-emitting print layer (32) is laminated on top of the first light-emitting print layer (31) using a second light-emitting ink containing a second light-emitting element to form the first light-emitting image layer (3) (S2-1). More specifically, the second light-emitting print layer (32) is laminated on top of the first light-emitting print layer (31) by applying the second light-emitting ink to the upper surface of the first light-emitting print layer (31).

[0079] Next, in the laser irradiation step (S2), the first light-emitting image layer (3) is irradiated with the first laser based on the first color data (411) of the reddish-brown component, and a second grayscale light emission pattern (321) is formed on the second light-emitting printing layer (32). Specifically, the irradiation conditions of the first laser are adjusted to irradiate the first light-emitting image layer (3) with the first laser, and the light emission intensity of the second light emitter is reduced compared to before irradiation with the first laser to form the second grayscale light emission pattern (321). At this time, the degree of deactivation of the second light emitter is adjusted. As a result, the second grayscale light emission pattern (321) has a second grayscale emission that shows a change in the intensity of the second visible light emission.

[0080] Next, the first light-emitting image layer (3) is irradiated with a second laser based on the second color data (412) of the black component, and a first grayscale light emission pattern (311) is formed on the first light-emitting printing layer (31). Specifically, the irradiation conditions of the second laser are adjusted to irradiate the first light-emitting printing layer (31) with the second laser, and the first grayscale light emission pattern (311) is formed by lowering the light emission intensity of the first light emitter compared to before laser irradiation (S2-2). At this time, the degree of deactivation of the first light emitter is adjusted. As a result, the first grayscale light emission pattern (311) has a first grayscale emission that shows the change in the density of the first visible light emission. In addition, at least a portion of the second light-emitting printing layer (32) is formed such that a black-based second grayscale light emission pattern (321) with a lower light emission intensity than the second grayscale light emission pattern (321) formed by the first laser does not overlap.

[0081] According to the manufacturing method of this embodiment, it is possible to manufacture an luminescent image forming body (1) in which a luminescent image (4) formed by additive color mixing of the first gradation emission of a first gradation emission pattern (311) emitted by excitation light and the second gradation emission of a second gradation emission pattern (321) emitted by excitation light is visible. As a result, it is possible to manufacture an luminescent image forming body (1) in which the luminescent image (4) is visible as a gradation image formed by emission of multiple colors, i.e., a color gradation image.

[0082] Furthermore, in the flowchart shown in Figure 11(b), a grayscale image can be formed by performing only the step of forming the second grayscale emission pattern by irradiation with the first laser (S2-1), which involves the first visible emission and the second grayscale emission pattern (321). Also, a grayscale image can be formed by performing only the step of forming the first grayscale emission pattern by irradiation with the second laser (S2-2), which involves the second visible emission and the first grayscale emission pattern (311).

[0083] Next, a method for manufacturing the light-emitting image forming body (1'') according to the second embodiment of the present invention will be described with reference to the drawings. Figure 13 is a flowchart showing the method for manufacturing the light-emitting image forming body'' according to the second embodiment of the present invention. Note that the basic manufacturing method is the same as that shown in Figure 11(a) and will therefore be omitted.

[0084] First, the process (S0) of decomposing the image data (41) that serves as the base image for the luminescent image (4) (see, for example, Figure 1) into color data for each predetermined color system component is the same as in Figure 11(b). Next, in the luminescent image layer formation process (S1), a second luminescent image layer (34) is formed on the substrate (2) using a luminescent ink containing a first luminescent element and a second luminescent element. Specifically, the second luminescent image layer (34) is formed on the substrate (2) by applying a luminescent ink, in which the first luminescent element and the second luminescent element are blended in a predetermined ratio, to the upper surface of the substrate (2).

[0085] Next, in the laser irradiation step (S2), the second light-emitting image layer (34) is irradiated with the first laser based on the first color data (411) of the reddish-brown component, and a second grayscale light emission pattern (321) is formed on the second light-emitting image layer (34) (S2-1). Specifically, the irradiation conditions of the first laser are adjusted as appropriate according to the density of the first color data (411), and the second light-emitting image layer (34) is irradiated with the first laser, thereby lowering the light emission intensity of the second light emitter compared to before irradiation with the first laser and forming a second grayscale light emission pattern (342). At this time, the degree of deactivation of the second light emitter is adjusted. As a result, the second grayscale light emission pattern (342) has a second grayscale emission that shows a change in the density of the second visible light emission.

[0086] Next, after forming the second grayscale emission pattern (342), the first grayscale emission pattern (341) is formed on the second emission image layer (34) by irradiation with a second laser based on the second color data (412) of the black component. Specifically, the laser irradiation conditions are adjusted as appropriate to the density of the second color data (412), and the laser is irradiated onto the second emission image layer (34) to form the first grayscale emission pattern (341) by lowering the emission intensity of the first emitter compared to before laser irradiation (S2-2). At this time, the degree of deactivation of the first emitter is adjusted. As a result, the first grayscale emission pattern (341) has a first grayscale emission that shows a change in the density of the first visible emission. In addition, at least a part of the second emission image layer (34) is formed by irradiation with the second laser so that a black-based second grayscale emission pattern (342) with a lower emission intensity than the second grayscale emission pattern (342) formed by the first laser does not overlap.

[0087] Furthermore, in the flowchart shown in Figure 13(b), a grayscale image can be formed by performing only the step of forming the second grayscale emission pattern by irradiation with the first laser (S2-1), using the first visible light emission and the second grayscale emission pattern (342). Also, a grayscale image can be formed by performing only the step of forming the first grayscale emission pattern by irradiation with the second laser (S2-2), using the second visible light emission and the first grayscale emission pattern (341).

[0088] According to the manufacturing method of this embodiment, since a light-emitting image forming body (1'') can be formed with a single layer of light-emitting ink, the number of manufacturing steps can be reduced and the manufacturing process can be simplified, while the same effects as described above with respect to Figures 11 and 12 can be obtained.

[0089] (Example 1) Next, an example of the results of the studies conducted by the inventors will be described with reference to the drawings. Figure 14 is a table illustrating an example of the results of the studies conducted by the inventors.

[0090] First, as Example 1, a UV offset ink containing 10% by weight of an inorganic red light-emitting pigment (manufactured by Nemoto Special Chemicals Co., Ltd.) was applied to the upper surface of the substrate (2) to form a first light-emitting printing layer (31) on the substrate (2). The inorganic red light-emitting pigment in this study is an example of the first light-emitting material described above with respect to Figures 1 to 13.

[0091] Next, a UV offset ink containing 5% by weight of organic green light-emitting pigment (manufactured by Honeywell Japan) was applied to the upper surface of the first light-emitting printing layer (31) to laminate the second light-emitting printing layer (32) on top of the first light-emitting printing layer (31) and create the first light-emitting image layer (3). The organic green light-emitting pigment in this Example 1 is an example of the second light-emitting body described above with respect to Figures 1 to 13.

[0092] Next, with respect to Figure 12, a 355 nm UV laser was irradiated onto the first emission image layer (3) based on the first color data (411) of the reddish-brown component mentioned above, and the irradiation position of the laser was moved at a speed of 2,000 millimeters / second (mm / s) to deactivate the organic green emission pigment. This UV laser irradiation was the first laser irradiation.

[0093] Next, with respect to Figure 12, a 355 nm UV laser was irradiated onto the first emission image layer (3) based on the second color data (412) of the black components mentioned above. The laser irradiation position was moved at a speed of 2,000 mm / s to deactivate the inorganic red emission pigment and the organic green emission pigment. This UV laser irradiation was the second laser irradiation. The energy of the UV laser in the second laser irradiation was higher than the energy of the UV laser in the first laser irradiation.

[0094] In this manner, a 355 nm UV laser was irradiated onto the second light-emitting printing layer (32), and while changing the laser irradiation conditions (e.g., frequency), a first-tone light-emitting pattern (311) was formed on the first light-emitting printing layer (31), and a second-tone light-emitting pattern (321) was formed on the second light-emitting printing layer (32) at a position where it overlapped with the first-tone light-emitting pattern (311). As a result, the light-emitting image forming body (3) described above with respect to Figures 1 to 4 was completed. In this embodiment 1, a face image was formed as the light-emitting image (4).

[0095] Next, ultraviolet light with a wavelength of 365 nm (UV-A) was irradiated onto the light-emitting image-forming material (3), and the light-emitting image (4) was observed. At this time, the red light-emitting pigment did not emit light, and a grayscale image was observed consisting only of green emission from the green light-emitting pigment. In other words, the light-emitting image (4) observed at this time was simply a grayscale image of light and dark based on the emission color (green) of the green light-emitting pigment.

[0096] Next, ultraviolet light (UV-C) with a wavelength of 254 nm was irradiated onto the light-emitting image-forming material (3), and the light-emitting image (4) was observed. At this time, as shown in Figure 14, in the background area not irradiated with the UV laser, i.e., in the area where the red light-emitting pigment and the green light-emitting pigment were active, yellow emission was observed as an additive color mixing of red and green emission. In the light-emitting image (4), red emission was observed in the area where the red light-emitting pigment was active and the green light-emitting pigment was deactivated. In the light-emitting image (4), a mixture of red emission and black was observed in the area where the red light-emitting pigment and the green light-emitting pigment were deactivated. In the light-emitting image (4), in the area where the red light-emitting pigment and the green light-emitting pigment were deactivated, neither the red nor the green light-emitting pigment emitted light, and black coloration was observed due to carbonization of the organic components of the phosphor by the laser, or discoloration due to thermal changes in the inorganic components.

[0097] According to the results of this embodiment 1, when the light-emitting image forming body (3) was irradiated with ultraviolet light (UV-A) with a wavelength of 365 nm, the light-emitting image (4) could be viewed as a grayscale image due to monochromatic emission. On the other hand, when the light-emitting image forming body (3) was irradiated with ultraviolet light (UV-C) with a wavelength of 254 nm, the light-emitting image (4) could be viewed as a grayscale image due to multiple colors of emission, i.e., a color grayscale image. This confirmed that a highly confidential anti-counterfeiting element can be formed through a simple manufacturing process. Furthermore, the inventors found that when the light-emitting image forming body (3) was irradiated with ultraviolet light (UV-C) with a wavelength of 254 nm, the facial image in the light-emitting image (4) could be viewed as a grayscale image of skin tone.

[0098] (Example 2) As Example 2, a second emission image layer (34) was formed on the substrate (2) by applying a UV offset ink containing 10% by weight of an inorganic red emission pigment (manufactured by Nemoto Special Chemicals Co., Ltd.) and 5% by weight of an organic green emission pigment (manufactured by Honeywell Japan Co., Ltd.) to the upper surface of the substrate (2). The mixing ratio of the inorganic red emission pigment and the organic green emission pigment was adjusted so that the UV offset ink emits yellow light when excited by a predetermined wavelength of light. The inorganic red emission pigment in this study is an example of the first emission body described above with respect to Figures 1 to 13. The organic green emission pigment in Example 2 is an example of the second emission body described above with respect to Figures 1 to 13.

[0099] Next, regarding Figure 12, a 355 nm UV laser was irradiated onto the second emission image layer (34) based on the first color data (411) of the reddish-brown component mentioned above, to deactivate the organic green emission pigment. The UV laser irradiation conditions were as follows: the laser irradiation position movement speed was 2,000 mm / s; the laser frequency was 100 kilohertz (kHz); and the resolution was 1,200 dpi. This UV laser irradiation was the first laser irradiation.

[0100] Next, with respect to Figure 12, a 355 nm UV laser was irradiated onto the second emission image layer (34) based on the second color data (412) of the black components mentioned above, to deactivate the inorganic red emission pigment and the organic green emission pigment. The UV laser irradiation conditions were as follows: the laser irradiation position movement speed was 2,000 mm / s; the laser frequency was 80 kHz; and the resolution was 1,200 dpi. This UV laser irradiation was the second laser irradiation.

[0101] In this manner, a 355 nm UV laser was irradiated onto the second light-emitting image layer (34), and while changing the laser irradiation conditions (e.g., frequency), the first grayscale light-emitting pattern (341) was formed on the second light-emitting image layer (34), and the second grayscale light-emitting pattern (342) was formed on the second light-emitting image layer (34) at a position where it overlapped with the first grayscale light-emitting pattern (341). As a result, the light-emitting image forming body (1'') described above was completed with respect to Figures 7 to 10. In this embodiment 2, a face image was formed as the light-emitting image (4).

[0102] Next, ultraviolet light (UV-A) with a wavelength of 365 nm was irradiated onto the light-emitting image-forming material (1''), and the light-emitting image (4) was observed. At this time, the red light-emitting pigment did not emit light, and a grayscale image was observed consisting only of green emission from the green light-emitting pigment. In other words, the light-emitting image (4) observed at this time is simply a grayscale image of light and dark based on the emission color (green) of the green light-emitting pigment.

[0103] Next, ultraviolet light (UV-B) with a wavelength of 302 nm was irradiated onto the light-emitting image-forming material (1''), and the emission image (4) was observed. At this time, the emission of multiple colors as described above was observed in Figure 14.

[0104] According to the results of this study, when the light-emitting image-forming body (1'') was irradiated with ultraviolet light (UV-A) with a wavelength of 365 nm, the emitted image (4) could be seen as a grayscale image due to monochromatic emission. On the other hand, when the light-emitting image-forming body (1'') was irradiated with ultraviolet light (UV-B) with a wavelength of 302 nm, the emitted image (4) could be seen as a grayscale image due to multiple colors of emission, i.e., a color grayscale image. As a result, the same effect as described above was obtained for Example 1.

[0105] Embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the claims. The configurations of the above embodiments can be partially omitted or combined in any way different from those described above. [Explanation of symbols]

[0106] 1: Light-emitting image forming body 1': Light-emitting image forming body 1'': Light-emitting image forming body, 2: Substrate, 3: First light-emitting image layer, 4: Light-emitting image, 31: First light-emitting printing layer, 32: Second light-emitting printing layer, 33: Third light-emitting printing layer, 34: Second light-emitting image layer, 41: Image data, 311: First grayscale light-emitting pattern, 321: Second grayscale light-emitting pattern, 331: Third grayscale light-emitting pattern, 341: First grayscale light-emitting pattern, 342: Second grayscale light-emitting pattern, 411: First color data, 412: Second color data

Claims

1. A light-emitting image forming body comprising: a first light-emitting printing layer formed on a substrate using a first light-emitting ink containing a first light-emitting element that emits first visible light when excited by a predetermined wavelength; and a first light-emitting image layer laminated on the first light-emitting printing layer, the first light-emitting image layer having a second light-emitting printing layer formed on the first light-emitting printing layer using a second light-emitting ink containing a second light-emitting element that emits second visible light when excited by the excitation light, The first emission image layer is, i) The first light-emitting printing layer has at least a portion of a first grayscale light emission pattern that produces a first grayscale light emission with a lower light intensity than the first visible light emission, and the emission image obtained by additive color mixing of the first grayscale light emission pattern and the second visible light emission is visible when the excitation light is used, or ii) The second light-emitting printing layer has at least a portion of a second grayscale light-emitting pattern that produces a second grayscale light-emitting pattern with a lower light intensity than the second visible light-emitting pattern, and the emission image obtained by additive color mixing of the second grayscale light-emitting pattern and the first visible light-emitting pattern is visible to the excitation light, or iii) A light-emitting image forming body characterized in that the first light-emitting printing layer has at least a portion of a first grayscale light-emitting pattern that produces a first grayscale light-emitting with a light-emitting intensity lower than the first visible light-emitting layer, and the second light-emitting printing layer has at least a portion of a second grayscale light-emitting pattern that produces a second grayscale light-emitting with a light-emitting intensity lower than the second visible light-emitting layer, and an emission image formed by additive color mixing of the first grayscale light-emitting pattern and the second grayscale light-emitting pattern is visible when excited by the excitation light.

2. The first light-emitting image layer is further laminated with a third light-emitting printing layer formed of a third light-emitting ink containing a third light-emitting element that emits a third visible light emission when excited by the excitation light, and the third light-emitting printing layer has at least a portion of a third grayscale light emission pattern that emits a third grayscale light emission with a lower light emission intensity than the third visible light emission, and the light-emitting image is further additively mixed with the third grayscale light emission pattern when excited by the excitation light to become visible, as described in claim 1.

3. The light-emitting image forming body according to claim 1, characterized in that the first light-emitting image layer is further laminated with a third color layer formed by an ink containing a third colorant that subtractively mixes the mixed light of the first visible light and the second visible light.

4. A light-emitting image forming body having a second light-emitting image layer formed on at least a portion of a substrate using a light-emitting ink containing a first light-emitting element that emits first visible light when excited by a predetermined wavelength, and a second light-emitting element that emits second visible light when excited by the same light, The aforementioned second emission image layer is iv) Having at least a portion of a first-tone emission pattern that produces a first-tone emission with a lower emission intensity than the first visible emission, and the emission image obtained by additive color mixing of the first-tone emission pattern and the second visible emission is visible by the excitation light, or V) Having at least a portion of a second-tone emission pattern that produces a second-tone emission with a lower emission intensity than the second visible emission, and the emission image obtained by additive color mixing of the second-tone emission pattern and the first visible emission is visible by the excitation light, or Vi) A light-emitting image forming body characterized in that it has at least a portion of a first grayscale light emission pattern that produces a first grayscale light emission with a lower light emission intensity than the first visible light emission, and a second grayscale light emission pattern that produces a second grayscale light emission with a lower light emission intensity than the second visible light emission, and that a light emission image formed by additive color mixing of the first grayscale light emission pattern and the second grayscale light emission pattern is visible when excited by the excitation light.

5. The second light-emitting image layer is formed from the light-emitting ink further containing a third light-emitting element that emits a third visible light emission upon excitation light, and has at least a portion of a third grayscale light emission pattern that emits a third grayscale light emission with a lower light emission intensity than the third visible light emission, and the light-emitting image is further additively mixed with the third grayscale light emission pattern upon excitation light to become visible, as described in claim 4.

6. The light-emitting image forming body according to claim 4, characterized in that the light-emitting ink contains a third colorant that subtractively mixes the mixed light of the first visible light and the second visible light.

7. The light-emitting image forming body according to claim 1 or 4, characterized in that the substrate contains a third colorant that subtractively mixes the mixed light of the first visible light and the second visible light.

8. A method for producing an emitting image formed body comprising a emitting image layer formation step of forming a first emitting image layer, and a laser irradiation step of irradiating the first emitting image layer with a laser after the emitting image layer formation step, The light-emitting image layer formation step involves laminating a first light-emitting print layer formed with a first light-emitting ink containing a first light-emitting element that emits first visible light when excited with a predetermined wavelength, and a second light-emitting print layer formed with a second light-emitting ink containing a second light-emitting element that emits second visible light when excited with the predetermined wavelength, to form the first light-emitting image layer on at least a portion of the substrate. The laser irradiation step is, Viii) The first laser is irradiated onto the first light-emitting image layer to deactivate the second light-emitting element, thereby forming a second grayscale light-emitting pattern on at least a portion of the second light-emitting printing layer that produces a second grayscale light emission with a light emission intensity lower than that of the second visible light emission, or Viii) The first light-emitting image layer is irradiated with a second laser to deactivate the first light-emitting element, thereby forming a first-tone light-emitting pattern on at least a portion of the first light-emitting printing layer that produces a first-tone light-emitting pattern with a light-emitting intensity lower than that of the first visible light-emitting element, or i) A method for producing an emissive image forming body, characterized by irradiating the first emissive image layer with a first laser to deactivate the second emissive, thereby forming a second grayscale emission pattern on at least a portion of the second emissive printing layer that produces a second grayscale emission with an emission intensity lower than that of the second visible emission; irradiating the first emissive image layer with a second laser to deactivate the first emissive and the second emissive, thereby further forming an emission pattern on at least a portion of the second emissive printing layer at a position that does not overlap with the second grayscale emission pattern formed by the first laser, with an emission intensity lower than that of the second grayscale emission pattern; and forming a first grayscale emission pattern on at least a portion of the first emissive printing layer that produces a first grayscale emission with an emission intensity lower than that of the first visible emission.

9. A method for producing an emitting image formed body comprising a emitting image layer formation step of forming a second emitting image layer, and a laser irradiation step of irradiating the second emitting image layer with a laser after the emitting image layer formation step, The light-emitting image layer formation step involves forming the second light-emitting image layer on at least a portion of the substrate using a light-emitting ink containing a first light-emitting element that emits first visible light when excited by a predetermined wavelength and a second light-emitting element that emits second visible light when excited by the predetermined wavelength. The laser irradiation step is, X) The first laser is irradiated onto the second light-emitting image layer to deactivate the second light-emitting element, thereby forming a second-tone emission pattern on at least a portion of the second light-emitting image layer that produces a second-tone emission with an emission intensity lower than that of the second visible light emission, or Xi) Irradiate the second light-emitting image layer with a second laser to deactivate the first light-emitting element, thereby forming a first-tone emission pattern on at least a portion of the second light-emitting image layer that produces a first-tone emission with an emission intensity lower than that of the first visible emission, or Xi) A method for producing an emitting image forming body, characterized by irradiating the second emitting image layer with a first laser to deactivate the second light emitter, thereby forming a second grayscale emission pattern on at least a portion of the second emitting image layer that produces a second grayscale emission with an emission intensity lower than that of the second visible light; irradiating the second emitting image layer with a second laser to deactivate the first light emitter and the second light emitter, thereby further forming an emission pattern on at least a portion of the second emitting image layer at a position that does not overlap with the second grayscale emission pattern formed by the first laser, with an emission intensity lower than that of the second grayscale emission pattern; and forming a first grayscale emission pattern on at least a portion of the second emitting image layer that produces a first grayscale emission with an emission intensity lower than that of the first visible light.

Images