JP2018200410A - Medium and method for manufacturing medium - Google Patents

Abstract

To provide a medium that can improve visibility and can have excellent design properties, and a method for manufacturing the medium.SOLUTION: A medium 100 includes: a retroreflection sheet 10 having a plurality of spherical bodies 12 for retro-reflecting incident light; and a convex lens layer 20 on the retroreflection sheet 10, the convex lens layer covering the spherical bodies 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a medium and a method for manufacturing the medium.

  2. Description of the Related Art Conventionally, an image sheet that secures image visibility by forming an image or the like on a retroreflective sheet is known (see, for example, Patent Document 1).

JP 2002-014616 A

  Since the image sheet described in Patent Document 1 has a configuration in which, for example, a transparent film on which an image is formed is bonded onto a retroreflective sheet, the image sheet has a monotonous design as a whole. In recent years, a medium for forming an image or the like on such a retroreflective sheet has been required to have a structure with excellent design while improving visibility.

  The present invention has been made in view of the above, and an object of the present invention is to provide a medium that can improve visibility and is excellent in design and a method for manufacturing the medium.

  A medium according to the present invention includes a retroreflective sheet having a plurality of spherical bodies that retroreflect incident light, and a convex lens layer formed on the retroreflective sheet so as to straddle the plurality of spherical bodies. .

  According to this configuration, in the region where the retroreflective sheet is exposed, the surface of the retroreflective sheet can be visually recognized by retroreflection when viewed from the same direction as the direction in which the retroreflective sheet is irradiated with light. On the other hand, in the region where the lens layer is provided, the lens layer has a reflection mode different from the region where the retroreflective sheet is exposed. Therefore, a contrast is generated between the region where the lens layer is provided and the region where the retroreflective sheet is exposed, and an image based on the contrast becomes visible. As a result, it is possible to improve visibility and to provide media with excellent design.

  The medium may further include a colored layer that is disposed on a surface of the retroreflective sheet and colors the retroreflective sheet, and the lens layer may be disposed on the colored layer.

  According to this configuration, since the colored layer is provided, the visibility can be further improved and more various appearances can be provided.

  In the above medium, the colored layer may have light transmittance.

  According to this configuration, since the colored layer has light transmittance, the visibility can be further improved and more various appearances can be provided.

  In the above media, the lens layer may have a lens surface that is gently curved from a convex top portion to an edge portion.

  According to this configuration, since the lens layer has a curved lens surface so that the edge portion becomes gentle from the top portion, light interference can be effectively generated in the lens layer.

  In the above medium, the lens unit may be arranged in a striped pattern or a checkered pattern in a plan view.

  According to this configuration, it is possible to provide an image that has high visibility, can provide various appearances, and is excellent in design.

  The method for manufacturing a medium according to the present invention includes a discharge step of discharging a clear ink containing an ultraviolet curable ink onto a retroreflective sheet by an ink jet method, and a plurality of times of ultraviolet light with a predetermined time interval with respect to the discharged clear ink. And a curing step of gradually curing the clear ink by irradiation and forming a lens layer.

  According to this configuration, the clear ink discharged onto the retroreflective sheet is irradiated with ultraviolet rays in a plurality of times with a predetermined time interval, whereby the clear ink is gradually cured to form a lens layer. The shape of the lens layer can be a gently curved shape from the top portion to the edge portion. Thereby, a lens layer capable of effectively causing light interference can be formed.

  ADVANTAGE OF THE INVENTION According to this invention, the improvement of visibility can be aimed at and the manufacturing method of the medium excellent also in the design property can be provided.

FIG. 1 is a diagram illustrating an example of a medium according to the first embodiment. FIG. 2 is a diagram showing a configuration along the section AA in FIG. FIG. 3 is a diagram illustrating an example of a medium according to the second embodiment. FIG. 4 is a diagram showing a configuration along the BB cross section in FIG. 3. FIG. 5 is a diagram illustrating an example of a medium according to the third embodiment. FIG. 6 is an explanatory diagram showing a method for manufacturing a medium. FIG. 7 is an explanatory diagram showing a method for manufacturing a medium. FIG. 8 is an explanatory diagram showing a method for manufacturing a medium. FIG. 9 is an explanatory diagram showing a method for manufacturing a medium. FIG. 10 is an explanatory diagram showing a method for manufacturing a medium. FIG. 11 is a diagram illustrating a configuration in a plan view of a medium according to a modification. FIG. 12 is a diagram illustrating a configuration of the medium according to the modification in a plan view.

  Embodiments according to the present invention will be described below in detail with reference to the drawings. In addition, this invention is not limited by this embodiment. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined, and when there are a plurality of embodiments, the embodiments can be combined.

[First Embodiment]
FIG. 1 is a diagram illustrating an example of a medium 100 according to the first embodiment. FIG. 2 is a diagram showing a configuration along the section AA in FIG. As shown in FIGS. 1 and 2, the medium 100 includes a retroreflective sheet 10 and a lens layer 20.

  The retroreflective sheet 10 includes a base material 11, a plurality of spherical bodies 12, and a surface layer 13. As the substrate 11, paper, fabric, film, or the like can be used. The plurality of spherical bodies 12 are disposed on the base material 11. The spherical body 12 retroreflects incident light. The spherical body 12 is arranged vertically and horizontally on the base material 11. The diameter R1 of each spherical body 12 is about 40 μm, for example. As the spherical body 12, for example, glass beads are used. The surface layer 13 is disposed on the plurality of spherical bodies 12 so as to cover the plurality of spherical bodies 12. The surface layer 13 is formed using, for example, a transparent resin.

  For example, a plurality of lens layers 20 are arranged on the retroreflective sheet 10. The lens layer 20 is arranged in a predetermined pattern on the retroreflective sheet 10. The lens layer 20 is convex, for example, and is formed so as to straddle the plurality of spherical bodies 12 of the retroreflective sheet 10. Examples of the shape of the lens layer 20 in plan view include a circle, an ellipse, and a polygon (triangle, quadrangle, etc.). The dimension R2 of the lens layer 20 that has the minimum width in a plan view has a dimension of about 200 μm to 3 mm, for example. Thus, the lens layer 20 is formed in a dimension that can sufficiently span the plurality of spherical bodies 12.

  The lens layer 20 has a lens surface 21. The lens surface 21 is formed in a state of rising from the retroreflective sheet 10. The lens surface 21 has a top portion 22 and an edge portion 23. The top portion 22 is a portion having the highest height position in the normal direction of the retroreflective sheet with respect to the retroreflective sheet 10. The edge portion 23 is a boundary portion with the retroreflective sheet 10 and is a portion that represents the outer shape of the lens layer 20 in a plan view. The lens surface 21 has a gently curved shape from the top portion 22 to the edge portion 23.

  The lens layer 20 is formed using an ultraviolet curable ink and is a transparent layer. The lens layer 20 has a height (thickness) to the top portion 22 of, for example, 40 μm or more. The ultraviolet curable ink used for the lens layer 20 is an ink that is completely cured when irradiated with ultraviolet rays. As the ultraviolet curable ink, for example, “LH-100 Clear” manufactured by Mimaki Engineering or “LF-350 Clear” manufactured by Sakurai Co., Ltd. is used. By using these ultraviolet curable inks, for example, when the lens layer 20 is formed on the flexible retroreflective sheet 10, the retroreflective sheet 10 can be deformed even when the retroreflective sheet 10 is bent. It can follow and be deformed.

  In the medium 100 according to the present embodiment, in the region where the retroreflective sheet 10 is exposed, the light L1 incident on the retroreflective sheet 10 is retroreflected, and when viewed from the same direction as the incident direction of the light L1, The surface of the retroreflective sheet 10 becomes visible by reflection. On the other hand, in the region where the lens layer 20 is provided, the lens layer 20 has a reflection mode different from the region where the retroreflective sheet 10 is exposed. Therefore, contrast occurs between the region where the lens layer 20 is provided and the region where the retroreflective sheet 10 is exposed, and an image based on the contrast becomes visible. Thereby, the visibility can be improved and the medium 100 excellent in design can be provided.

  In the lens layer 20, a part of the light L2 incident on the lens layer 20 is reflected by the lens surface 21 of the lens layer 20, and the other part of the light L3 travels into the lens layer 20 to be a retroreflective sheet. 10 is reflected from the lens surface 21 of the lens layer 20. For this reason, the light L2 reflected by the lens surface 21 and the light L3 reflected by the retroreflective sheet 10 and emitted from the lens surface 21 may interfere with each other. In this case, the appearance changes as if an oil film floating on the water surface is seen according to the direction of viewing the lens layer 20.

  Further, when the external reflection light 10 and the lens layer 20 are irradiated from one direction and the medium 100 is viewed from the light irradiation direction in a state where the external light is not sufficiently irradiated, such as at night, for example, it is separated from the medium 100. When viewed from the above position, the entire surface of the retroreflective sheet 10 is visually recognized as being retroreflected. Further, when viewed from a position approaching the medium 100, the contrast between the region where the lens layer 20 is provided and the region where the retroreflective sheet 10 is exposed is visually recognized. As described above, the medium 100 can provide various appearances.

[Second Embodiment]
FIG. 3 is a diagram illustrating an example of the medium 200 according to the second embodiment. FIG. 4 is a diagram showing a configuration along the BB cross section in FIG. 3. As shown in FIGS. 3 and 4, the medium 200 includes a retroreflective sheet 10, a lens layer 20, and a colored layer 30. That is, in the medium 200 according to the present embodiment, the colored layer 30 is provided between the retroreflective sheet 10 and the lens layer 20. The configuration of the retroreflective sheet 10 is the same as in the first embodiment. In the present embodiment, a plurality of lens layers 20 are arranged in a predetermined pattern on the colored layer 30.

  The colored layer 30 is an image layer formed using an ultraviolet curable color ink. The colored layer 30 is formed on the surface layer 13 of the retroreflective sheet 10. In the present embodiment, the colored layer 30 has light transparency, but is not limited thereto, and may have a configuration that does not have light transparency. The image formed in the colored layer 30 includes, for example, a combination of characters and designs, or a solid coating that fills a predetermined area. The ultraviolet curable color ink used for the colored layer 30 is an ink that is completely cured when irradiated with ultraviolet rays. The complete curing means that the ultraviolet curable color ink is crosslinked by being irradiated with ultraviolet rays. As the ultraviolet curable color ink used for the colored layer 30, for example, “LH-100” manufactured by Mimaki Engineering or “LF-350” manufactured by Sakurai Co., Ltd. is used.

  In the medium 200 according to the present embodiment, in the region where the retroreflective sheet 10 is exposed, the light incident on the retroreflective sheet 10 is retroreflected, and when viewed from the same direction as the light incident direction, The surface of the retroreflective sheet 10 becomes visible. In the region where the colored layer 30 is exposed, the light L4 incident on the colored layer 30 is transmitted through the colored layer 30, is retroreflected by the retroreflective sheet 10, and is transmitted through the colored layer 30 in a direction opposite to the incident direction. proceed. For this reason, when viewed from the same direction as the incident direction of light, the colored light transmitted through the colored layer 30 becomes visible.

  Further, in the region where the lens layer 20 is provided, the lens layer 20 has a reflection mode different from the region where the colored layer 30 is exposed. Therefore, a contrast is generated between the region where the lens layer 20 is provided and the region where the colored layer 30 is exposed, and an image based on the contrast becomes visible. Thereby, coupled with the color sensation by the colored layer 30, the visibility can be improved, and the medium 100 excellent in design can be provided.

  In the lens layer 20, a part of the light L <b> 5 incident on the lens layer 20 is reflected by the lens surface 21 of the lens layer 20. Further, another part of the light L6 travels into the lens layer 20, passes through the colored layer 30, is retroreflected by the retroreflective sheet 10, returns through the colored layer 30, and is emitted from the lens surface 21 of the lens layer 20. The Therefore, the appearance changes depending on the direction in which the lens layer 20 is viewed by the light L5 and the light L6. Thereby, the visibility can be improved and the media 200 excellent in design can be provided.

  Further, when the external reflection light 10 and the lens layer 20 are irradiated from one direction and the medium 200 is viewed from the light irradiation direction in a state where outside light is not sufficiently irradiated, for example, at night, the distance from the medium 200 is increased. When viewed from the above position, the entire surface of the retroreflective sheet 10 is visually recognized as being retroreflected. Further, when viewed from a position close to the medium 200, the contrast between the region where the lens layer 20 is provided, the region where the colored layer 30 is exposed, and the region where the retroreflective sheet 10 is exposed is visually recognized. As described above, the media 200 can provide various appearances.

[Third Embodiment]
FIG. 5 is a diagram illustrating an example of the medium 300 according to the third embodiment. As shown in FIG. 5, the medium 300 includes a retroreflective sheet 10, a lens layer 20, a colored layer 30, and a transparent layer 40. In the medium 300 according to the present embodiment, the colored layer 30 and the transparent layer 40 are provided between the retroreflective sheet 10 and the lens layer 20. About the structure of the retroreflection sheet 10 and the colored layer 30, it is the same as that of 2nd Embodiment. In the present embodiment, a plurality of lens layers 20 are arranged in a predetermined pattern on the transparent layer 40.

  The transparent layer 40 is disposed so as to cover the colored layer 30 and protects the colored layer 30. The transparent layer 40 is formed using the same ultraviolet curable ink as the lens layer 20. Therefore, the ultraviolet curable ink used for the transparent layer 40 is an ink that is completely cured when irradiated with ultraviolet rays. For example, “LH-100 Clear” manufactured by Mimaki Engineering or “LF-350 Clear” manufactured by Sakurai Co., Ltd. Is used.

  Therefore, the medium 300 according to the present embodiment has a plurality of convex portions formed on the surface of the transparent layer 40, and the convex portions serve as the lens layer 20. For this reason, the colored layer 30 can be reliably protected. Moreover, since the convex part on the surface of the transparent layer 40 is used as the lens layer 20, the visibility can be improved as compared with a configuration in which a flat transparent layer is simply disposed on the colored layer.

[Production method]
Next, an embodiment of a method for manufacturing a medium will be described with reference to FIGS. 6 to 10 are explanatory diagrams showing a method for manufacturing a medium. In the following example, a case where the lens layer 20 of the medium 100 according to the first embodiment is formed, that is, a case where the lens layer 20 is directly formed on the retroreflective sheet 10 will be described. In addition, the formation process of the lens layer 20 demonstrated with the manufacturing method of the following media is also about the case where the lens layer 20 of the medium 200 which concerns on 2nd Embodiment, and the lens layer 20 of the medium 300 which concerns on 3rd Embodiment are formed. Similar explanations are possible. That is, when the lens layer 20 of the medium 200 according to the second embodiment is formed, the lens layer 20 is formed on the colored layer 30, and when the lens layer 20 of the medium 300 according to the third embodiment is formed, the transparent layer 40 is formed. To form.

  In the media manufacturing method according to the present embodiment, the ejection step ST1 and the curing steps ST2 to ST5 are sequentially performed. In the media manufacturing method according to the present embodiment, a printing apparatus having a carriage 50 on which an inkjet head 51 that discharges ultraviolet curable ink and an ultraviolet irradiation head 52 that irradiates ultraviolet light to the ultraviolet curable ink is used. Examples of such a printing apparatus include “UJF-3042” or “UJF-6042” manufactured by Mimaki Engineering.

  First, as shown in FIG. 6, in the ejection step ST1, the retroreflective sheet 10 is disposed at a predetermined position, and then the carriage 50 is scanned in the main scanning direction. Then, the ultraviolet curable ink is discharged from the nozzle 51 a of the inkjet head 51, and the ultraviolet curable ink Q discharged from the nozzle 51 a is landed on the retroreflective sheet 10.

  Next, curing steps ST2 to ST5 are performed. In the curing steps ST <b> 2 to ST <b> 5, the ultraviolet curable ink Q that has landed on the retroreflective sheet 10 is irradiated with ultraviolet rays in a plurality of times with a predetermined time interval, whereby the ultraviolet curable ink Q is gradually cured to be a lens. Layer 20 is formed. Specifically, after the ultraviolet curable ink Q on the retroreflective sheet 10 is semi-cured (temporarily cured), the shape of the lens layer 20 is formed, and then the ultraviolet curable ink Q is completely cured (mainly cured).

  As shown in FIG. 7, in the first irradiation step ST <b> 2, the carriage 50 is continuously scanned in the main scanning direction to move the ultraviolet irradiation head 52 backward in the moving direction of the inkjet head 51, and the ultraviolet irradiation head 52. Then, the ultraviolet curable ink Q is irradiated with ultraviolet U to be semi-cured. As described above, after the ultraviolet curable ink Q is discharged, it can be semi-cured by irradiating the ultraviolet ray U, so that the bleeding of the ultraviolet curable ink Q can be suppressed and the lens layer 20 can be formed with high definition. On the other hand, since the ultraviolet curable ink Q is in a semi-cured state, the edge portion of the ultraviolet curable ink Q landed on the retroreflective sheet 10 (the boundary portion between the ultraviolet curable ink Q and the landed retroreflective sheet 10). Becomes a gentle shape. In the first irradiation step ST2, after the ultraviolet curable ink Q has landed, it may be delayed by a predetermined time (for example, several seconds), and the ultraviolet curable ink Q may be irradiated with ultraviolet rays to be semi-cured.

  Next, as shown in FIG. 8, the carriage 50 is returned to the original position in the carriage return step ST3, and the carriage 50 is moved again in the main scanning direction. At this time, since the ultraviolet curable ink Q is in a semi-cured state, the edge portion continues to spread.

  Next, as shown in FIG. 9, in the second irradiation step ST <b> 4, the carriage 50 is scanned in the main scanning direction, and the ultraviolet irradiation head 52 is moved in the moving direction of the inkjet head 51 to move the ultraviolet irradiation. The ultraviolet curable ink Q is irradiated from the head 52 to the ultraviolet curable ink Q to be completely cured.

  Thereby, as shown in FIG. 10, the lens layer 20 is formed in the retroreflection sheet 10 (completion process ST5). The lens layer 20 is formed in a convex shape on the retroreflective sheet 10 so as to have a lens surface 21 having a gently curved shape from the convex top portion 22 to the edge portion 23. Since the carriage return step ST3 is sandwiched between the first irradiation step ST2 and the second irradiation step ST4, the time during which the edge portion of the ultraviolet curable ink Q spreads after the ultraviolet curable ink Q is semi-cured to fully cured. Can be secured.

  As described above, according to the manufacturing method according to the present embodiment, bleeding of the ultraviolet curable ink Q can be suppressed by semi-curing the ultraviolet curable ink Q. In addition, the edge portion of the ultraviolet curable ink Q that has landed on the retroreflective sheet 10 has a gentle shape during the time from the semi-curing of the ultraviolet curable ink Q to the complete curing. For this reason, since the lens layer 20 after complete curing has a shape having the lens surface 21 having a gently curved shape from the convex top portion 22 to the edge portion 23, the lens effect can be reliably exhibited.

  The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, the case where the lens layer 20 has a shape in plan view, for example, a circle, an ellipse, a polygon (triangle, quadrangle, etc.) has been described as an example, but is not limited thereto.

  FIG. 11 is a diagram illustrating a configuration in a plan view of a medium according to a modification. For example, like the medium 100A shown in FIG. 11, the lens layer 20 may be formed in a stripe shape in plan view. In the medium 100 </ b> A, a belt-like lens layer 20 </ b> A extending in one direction is arranged on the retroreflective sheet 10 so as to be arranged side by side in the width direction (short direction) of the lens layer 20 </ b> A. In this case, the lens surface 21A of the lens layer 20A can be configured to have a gentle shape over both ends in the width direction.

  FIG. 12 is a diagram illustrating a configuration of the medium according to the modification in a plan view. For example, like the medium 100B shown in FIG. 12, the lens layer 20B may be arranged in a checkered pattern in a plan view. In the medium 100 </ b> B, for example, a lens layer 20 </ b> B formed in a rectangular shape is arranged on the retroreflective sheet 10 so that each corner is in contact with each other. In this case, the lens surface 21 </ b> B of each lens layer 20 </ b> B can be configured to have a gentle shape from the central portion to the four sides in plan view.

  Further, for example, in the above-described embodiment, the case where so-called glossy printing is performed in the media manufacturing method has been described as an example, but the present invention is not limited to this. In the discharge process ST1 and the curing processes ST2 to ST5, the discharge amount, discharge timing, discharge period, and the like of the ultraviolet curable ink discharged from the inkjet head 51 are controlled, and the intensity of the ultraviolet light irradiated from the ultraviolet irradiation head 52, semi-curing, The lens layer 20 having a desired shape, thickness, area, dimension, and pattern can be obtained by controlling the timing of complete curing, the irradiation period, and the like.

  For example, in the ejection step ST1, the lens layer 20 may be formed by performing an overstrike in which the ultraviolet curable ink Q is landed multiple times at the same landing position. In this case, for example, the inkjet head 51 has a resolution of 1200 dpi × 1440 dpi, and printing can be performed in 8 passes. Note that the number of passes is not particularly limited, and may be, for example, 4 passes. When overprinting is performed, the amount of the ultraviolet curable ink ejected at each time is smaller than in the normal case where the overstrike is not performed (that is, when ultraviolet curable ink is ejected only once). It has become a thing. In addition, in the overstrike, the amount of the ultraviolet curable ink at each time can be made the same amount, but the present invention is not limited to this, and different amounts of ink may be ejected in at least one ejection operation.

  For example, in the case of performing overstrike, a case where the ultraviolet curable ink Q is discharged twice at the same landing position will be described as an example. In this case, the ink amount of the first ultraviolet curable ink Q and the ink amount of the second ultraviolet curable ink Q can be made the same amount. For example, the first and second ink amounts can be about 50% of the amount of ink ejected during normal operation (during normal printing). For this reason, the ink amount becomes 100% by performing the two-time overstrike. That is, the ink amount at each time is set to 50%, and printing is repeated twice under the printing condition based on the shape data of the lens layer 20.

  In this way, by performing overstrike, the dot diameter of the ultraviolet curable ink Q that has landed can be increased as compared with the case where the overstrike is not performed. Further, the lens layer 20 can be formed thin by reducing the amount of the ultraviolet curable ink Q that is ejected each time.

Q UV curable ink U UV ST1 Discharge process ST2 to ST5 Curing process 10 Retroreflective sheet 11 Base material 12 Spherical body 13 Surface layer 20, 20A, 20B Lens layer 21, 21A, 21B Lens surface 22 Top part 23 Edge part 30 Colored layer 40 Transparent layer 50 Carriage 51 Inkjet head 52 Ultraviolet irradiation head 100, 100A, 100B, 200, 300 Media

Claims (6)

A retroreflective sheet having a plurality of spherical bodies that retroreflect incident light;
A convex lens layer formed on the retroreflective sheet so as to straddle the plurality of spherical bodies. A coloring layer disposed on the surface of the retroreflective sheet and coloring the retroreflective sheet;
The medium according to claim 1, wherein the lens layer is disposed on the colored layer. The medium according to claim 2, wherein the colored layer has light transparency. The medium according to any one of claims 1 to 3, wherein the lens layer has a lens surface that is gently curved from a convex top portion to an edge portion. The medium according to any one of claims 1 to 4, wherein the lens unit is arranged in a striped pattern or a checkered pattern in a plan view. A discharge step of discharging a clear ink containing an ultraviolet curable ink onto a retroreflective sheet by an inkjet method;
A curing step of forming a lens layer by gradually curing the clear ink by irradiating the discharged clear ink with ultraviolet rays in a plurality of times with a predetermined time interval.

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